PA GI Bootcamp — Gastroenterology & Hepatology Syllabus

Domain 1 · Upper GI & Esophageal Disorders

Upper GI — Esophagus, Stomach, PUD

Tier 1

Topic 1

Gastroesophageal Reflux Disease (GERD)

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Clinical Diagnosis · PPI Timing · Barrett Esophagus · Alarm Symptoms

★★ High YieldPPI Traps

Why the PANCE Tests This

GERD affects ~20% of US adults. Boards test: alarm symptoms triggering endoscopy, PPI timing (before meals), Barrett esophagus screening, and the functional heartburn distinction. High frequency of PPI-related drug interaction questions.

Core Recognition Pattern

Classic: Heartburn (retrosternal burning) + regurgitation + worsens with meals/lying down/bending forward
Atypical: Chronic cough, hoarseness, laryngitis, non-cardiac chest pain, dental erosions, asthma exacerbation
Alarm symptoms (VBAD): Vomiting (persistent), Bleeding/anemia, Age >60 with new dyspepsia, Dysphagia/weight loss → endoscopy required

Diagnostic Workup

First-line: Clinical diagnosis — empiric 8-week PPI trial for classic symptoms WITHOUT alarm features
Upper endoscopy (EGD): For alarm symptoms, refractory GERD, or Barrett surveillance. Gold standard for mucosal assessment.
24-hour pH monitoring / impedance: Gold standard for quantifying acid exposure — used in refractory cases before surgery
NOT recommended: Barium swallow — poor sensitivity for mucosal disease, not a diagnostic GERD test

Treatment

Lifestyle (all patients): Weight loss (strongest evidence), elevate head of bed, avoid meals 2–3h before bed, smoking cessation
PPIs = first-line pharmacotherapy — superior to H2RAs for symptom relief AND healing erosive esophagitis
PPI timing: 30–60 minutes BEFORE a meal for optimal efficacy. NOT with meals, NOT at bedtime.
Duration: 8-week trial for uncomplicated GERD; attempt discontinuation if symptoms resolve. Lowest effective dose for maintenance.
LA Grade C/D esophagitis: Indefinite PPI therapy or antireflux surgery — do not attempt PPI discontinuation
Refractory GERD: Confirm timing/adherence → twice-daily PPI → endoscopy + reflux monitoring → consider functional heartburn (neuromodulators, not more acid suppression)

Los Angeles Esophagitis Classification

Grade	Mucosal Break Size	Management Implication
A	≤5 mm	Standard 8-week PPI course
B	>5 mm, not bridging folds	Standard 8-week PPI course
C	Bridging folds, <75% circumference	Indefinite PPI or antireflux surgery
D	≥75% circumference	Indefinite PPI or antireflux surgery

⚑ Board Traps — GERD

PPIs must be taken 30–60 minutes BEFORE meals — taking at bedtime or with meals reduces efficacy by 50%+
Barium swallow is NOT a diagnostic GERD test — boards commonly list it as a distractor
Functional heartburn ≠ GERD — normal acid exposure on pH monitoring, does NOT respond to PPIs; treat with neuromodulators (TCAs, SSRIs) or behavioral therapy
PPI long-term risks: C. diff, hypomagnesemia, B12 deficiency, bone fractures, CKD — observational data; the one proven association in RCT is increased enteric infections
Vonoprazan (P-CAB) is FDA-approved for erosive esophagitis — does NOT require pre-meal dosing (different from PPIs)

★ Memory Trick

PPI timing: "Take it BEFORE the meal, like a pre-game warmup" — 30-60 min pre-meal GERD alarm symptoms: "VBAD" — Vomiting, Bleeding/anemia, Age (>60), Dysphagia/weight loss → EGD LA Grade C/D = Chronic PPI or Cut (surgery) — never discontinue

Clinical Vignette

A 52-year-old obese man has 6 months of heartburn and regurgitation. He started omeprazole 20mg at bedtime 4 weeks ago with only partial improvement. No dysphagia or weight loss.

Answer: PPI is being taken at the wrong time. Switch to 30–60 minutes before breakfast. If still not controlled after 8 weeks: step up to twice-daily PPI. EGD not yet indicated — no alarm symptoms. Also counsel on weight loss (strongest lifestyle intervention).

Rapid Review Bullets

PPIs > H2RAs for erosive esophagitis
Alarm symptoms → EGD (not empiric PPI trial)
Barrett esophagus = specialized intestinal metaplasia → risk factor for esophageal adenocarcinoma
Barrett screening: Males ≥50 with ≥5 years GERD + ≥2 additional risk factors (obesity, smoking, family history)
Barrett surveillance: Low-grade dysplasia every 6–12 months; high-grade dysplasia → endoscopic eradication therapy

Tier 1

Topic 2

Peptic Ulcer Disease & H. pylori

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Gastric vs Duodenal Patterns · Eradication Regimens · Test of Cure

★★★ PANCE PriorityMany Traps

Why the PANCE Tests This

Highest-yield GI topic. Boards test: gastric vs. duodenal pain patterns, WHICH H. pylori test to use and WHEN, which eradication regimen, and test-of-cure timing. Multiple traps around biopsy requirements and false-negative testing.

Core Recognition Pattern

	Gastric Ulcer	Duodenal Ulcer
Pain timing	Food → Pain (eating worsens)	Pain → Food → Relief (2–3h after meal, nocturnal)
H. pylori	~60% of cases	~90% of cases (most common)
Malignancy risk	Yes — always biopsy	Extremely rare — biopsy not required
Other causes	NSAID use, Zollinger-Ellison	H. pylori, NSAID use

Diagnostic Approach

Age ≥60 + new dyspepsia: Upper endoscopy (EGD) — biopsy all gastric ulcers
Age <60, no alarm symptoms: Noninvasive H. pylori testing → treat if positive (test-and-treat strategy)
Best noninvasive tests: Urea breath test (UBT) or stool antigen test — both confirm ACTIVE infection
Serology (IgG antibody): Do NOT use — only shows prior exposure, cannot confirm active infection or eradication
Biopsy-based tests (during EGD): Rapid urease test (CLO test), histology, culture — all detect active infection

H. pylori Eradication — Treatment Regimens

Regimen	Drugs	Duration	Use When
Bismuth Quadruple (preferred US)	PPI + Bismuth + Tetracycline + Metronidazole	14 days	First-line — high clarithromycin resistance (~32% in US)
Concomitant (nonbismuth quad)	PPI + Clarithromycin + Amoxicillin + Metronidazole	14 days	~91% eradication rate
Clarithromycin Triple	PPI + Clarithromycin + Amoxicillin	14 days	Only if local clarithromycin resistance <15% — NOT recommended empirically in most US regions
Levofloxacin Triple (salvage)	PPI + Levofloxacin + Amoxicillin	14 days	Second-line after first regimen failure
Rifabutin-based (salvage)	PPI + Rifabutin + Amoxicillin	10–14 days	Third-line — ≥2 prior failures

Test of Cure: Urea breath test or stool antigen ≥4 weeks after completing therapy AND ≥2 weeks after stopping PPIs.

NSAID-Induced Ulcers

If NSAIDs can be stopped: PPI + H. pylori eradication if positive
If NSAIDs cannot be stopped: Co-administer PPI (misoprostol is an alternative but less tolerated)
Low CV risk patients: Consider COX-2 inhibitor + PPI (reduced GI risk vs. non-selective NSAID)

⚑ Board Traps — PUD & H. pylori

Gastric ulcers must always be biopsied — malignancy risk. Duodenal ulcers almost never malignant.
Stop PPIs ≥2 weeks before UBT or stool antigen — PPIs suppress H. pylori activity → false negatives
H. pylori serology CANNOT confirm active infection — positive serology only proves prior exposure
Clarithromycin triple therapy is no longer first-line in most US regions — high resistance rates (~32%)
Test of cure is mandatory after H. pylori treatment — do NOT assume eradication without confirmation
Zollinger-Ellison syndrome (gastrinoma): Multiple ulcers in unusual locations (duodenum, jejunum), diarrhea, refractory to PPI. Check fasting serum gastrin level.

★ Memory Trick

Gastric ulcer: "Food = Foe" (pain with food) Duodenal ulcer: "Food = Friend" (pain relieved by food, worse when empty) H. pylori testing: "Stop the PPI 2 weeks before the test or you'll miss the pest" Bismuth quad = "BMAT" — Bismuth + Metronidazole + Amoxicillin + Tetracycline + PPI

Clinical Vignette

A 44-year-old woman has epigastric pain that worsens 2–3 hours after meals and wakes her at 3 AM. It is relieved by eating crackers. EGD shows a 1.2 cm duodenal ulcer. H. pylori stool antigen is positive. What is the next step?

Answer: H. pylori eradication with bismuth quadruple therapy × 14 days (preferred in US given clarithromycin resistance). After completion, stop PPI for 2 weeks then confirm eradication with repeat stool antigen or urea breath test. No biopsy required for duodenal ulcers (very low malignancy risk).

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These 2 topics are free — a real look at how we teach. The remaining 20 topics below, along with interactive diagrams, EKG popups, Module D differentials, Module E board pearls, and audio mnemonics, are included with bootcamp enrollment.

Everything in the full GI & Hepatology syllabus

22 fully-worked clinical topics

Interactive SVG anatomy diagrams

Module D — must-know differentials

Module E — domain board pearls

Animated EKG strips & 12-lead viewer

Audio mnemonics per topic

20 PANCE-style board questions

Clinical vignettes + teaching pearls

🔒 Upper GI Bleeding 🔒 Variceal Hemorrhage & Portal Hypertension 🔒 Cirrhosis & Its Complications 🔒 Hepatitis B Serology 🔒 Liver Enzyme Patterns & Acetaminophen Toxi 🔒 Lower GI Bleeding 🔒 Inflammatory Bowel Disease 🔒 Colorectal Cancer Screening & Surveillance 🔒 Acute Pancreatitis 🔒 Biliary Tract Disease 🔒 Celiac Disease (Gluten-Sensitive Enteropat 🔒 Chronic Pancreatitis 🔒 Irritable Bowel Syndrome (IBS) 🔒 Diverticular Disease + 6 more topics

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📚5 complete systems

🎯Pre & post-rotation assessment

📟Full EKG library

🩺84 clinical vignettes

👨‍⚕️Dr. Rajiv Choudhary, MD MPH

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Tier 1

Topic 3

Upper GI Bleeding

Glasgow-Blatchford · Endoscopic Management · Transfusion Threshold

★★★ PANCE PriorityTransfusion Trap

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Core Recognition Pattern

Hematemesis: Bright red blood or coffee-ground emesis — proximal to ligament of Treitz
Melena: Black, tarry, malodorous stools — blood digested in upper GI tract (need ≥50–100 mL blood)
Hematochezia from UGIB: Massive bleeding can present with bright red blood per rectum + hemodynamic instability
Most common causes: Peptic ulcer disease (most common), gastric/esophageal varices, Mallory-Weiss tear, AV malformations

Initial Management — Before Endoscopy

IV access × 2 large-bore, volume resuscitation
Transfusion threshold: Hgb <7 g/dL (restrictive strategy) — higher threshold (8–9) for active cardiovascular disease
IV PPI (bolus + infusion): Reduces high-risk stigmata at endoscopy — does NOT reduce mortality
Erythromycin 250mg IV 30–120 min before endoscopy: Prokinetic — clears blood from stomach, improves visualization
Tranexamic acid: Do NOT use — HALT-IT trial: no benefit, possible harm
Glasgow-Blatchford Score 0–1: Very low risk → consider outpatient management with endoscopy within 24 hours

Endoscopic Management — PANCE Approach

PANCE tests the indication for endoscopy and timing — not Forrest Classification:

When to scope: Urgent EGD within 24 hours of presentation for most UGIB. Within 12 hours if hemodynamically unstable or cirrhotic with suspected varices
Pre-endoscopy: IV PPI (80mg bolus → 8mg/hr infusion) — reduces need for intervention and rebleeding
High-risk endoscopic findings: Active arterial spurting, visible vessel, adherent clot → endoscopic hemostasis required
Low-risk findings: Clean ulcer base, flat pigmentation → discharge may be appropriate after observation
Post-endoscopy: High-risk findings → IV PPI 72 hours then oral PPI. Continue H. pylori treatment if positive.

🩺 PANCE Pearl: Transfusion threshold = Hgb <7 (or <8 if CAD). Do NOT transfuse to Hgb >9 in variceal bleeders — worsens portal pressure and increases mortality.

⚑ Board Traps — UGIB

Transfusion threshold is Hgb 7 g/dL, NOT 10 — over-transfusion increases rebleeding risk and portal pressure (especially in variceal bleeding)
Epinephrine injection alone is INADEQUATE — must combine with a second modality (thermal or mechanical)
Tranexamic acid is NOT recommended for GI bleeding — HALT-IT trial proved no benefit, possible increased thromboembolic risk
IV PPI reduces need for endoscopic therapy but does NOT reduce mortality
Endoscopy timing: Within 24 hours for most; within 12 hours for hemodynamically unstable (after resuscitation)
Clean ulcer base: Very low rebleeding risk — can discharge early with oral PPI; no endoscopic therapy needed

★ Memory Trick

"Active arterial bleed or visible vessel = endoscopic treatment required. Clean base or flat pigment = low risk, discharge with oral PPI." Epi injection alone = "Half a job" — always add thermal or clips Transfusion: "7 is the magic number" — transfuse at Hgb <7, target 7–9 "Erythromycin clears the view" — give 30-120 min before scope

Tier 1

Topic 4

Variceal Hemorrhage & Portal Hypertension

Octreotide · Banding · TIPS · Carvedilol Prophylaxis

★★ High YieldOver-Transfusion Trap

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Acute Variceal Hemorrhage — The Simultaneous Protocol

All 5 Interventions Started Simultaneously

Octreotide: 50 mcg IV bolus → 25–50 mcg/hr infusion × 2–5 days. Reduces portal pressure immediately.
Prophylactic antibiotics: IV ceftriaxone 1g daily × 5 days. Reduces mortality AND infection rates.
Restrictive transfusion: Target Hgb ~7 g/dL. Over-transfusion ↑ portal pressure → worsens bleeding.
Endoscopy within 12 hours: Esophageal variceal ligation (EVL/banding) is standard therapy.
Erythromycin 125–250 mg IV pre-endoscopy to improve gastric visualization.

Rescue TIPS

For high-risk patients: Child-Pugh B with active bleeding or Child-Pugh C (10–13 points)
Early TIPS within 72 hours of admission improves survival in these groups

Prophylaxis — Primary & Secondary

Goal	First-Line	Alternative	Board Key
Primary (prevent 1st bleed)	Carvedilol 6.25–12.5 mg/day (preferred NSBB per Baveno VII) OR propranolol/nadolol	EVL if beta-blockers contraindicated/intolerated	Carvedilol preferred — also reduces intrahepatic resistance via alpha-blocking
Secondary (prevent rebleed)	NSBB (carvedilol/propranolol) + EVL (every 2–4 weeks until variceal obliteration)	TIPS if rebleeds despite combination	Combination therapy — not either/or

⚑ Board Traps — Variceal Bleeding

Do NOT over-transfuse in variceal bleeding — target Hgb ~7. Raising Hgb above 9 increases portal pressure and precipitates rebleeding.
INR does NOT predict bleeding risk in cirrhosis — do NOT give FFP or vitamin K prophylactically before paracentesis or endoscopy in cirrhosis
Prophylactic antibiotics reduce mortality in variceal bleeding — this is mandatory, not optional. Ceftriaxone 1g daily × 5 days.
Carvedilol is preferred over propranolol/nadolol for variceal prophylaxis per Baveno VII — different from HFrEF where carvedilol is also evidence-based (same drug, two different contexts)
NSBB + EVL for secondary prophylaxis — monotherapy with either alone is inferior to combination

★ Memory Trick

Acute variceal bleed = "OCTET": Octreotide + Ceftriaxone + Transfusion (restrictive) + Endoscopy + Erythromycin (pre-scope) Secondary prophylaxis: "Band and Block" — EVL banding + Non-selective beta-blocker (carvedilol) "Cirrhosis INR = not useful for bleeding risk" — DO NOT use INR to guide pre-procedure FFP

Domain 2 · Hepatology & Liver Disease

Hepatology — Cirrhosis, Viral Hepatitis, Liver Failure

Tier 1

Topic 5

Cirrhosis & Its Complications

Ascites · SBP · Hepatic Encephalopathy · Hepatorenal Syndrome

★★★ PANCE PriorityMany Traps

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Staging & Prognosis

Score	Components	Clinical Use	Board Key
Child-Pugh	"ABCDE": Albumin, Bilirubin, Coagulation (INR), Distension (ascites), Encephalopathy	Prognosis + surgical risk stratification	Class A (5–6) = compensated; Class B (7–9) = moderate; Class C (10–15) = decompensated
MELD Score	Predicts 90-day transplant mortality. Higher score = higher priority for transplant listing.	Liver transplant listing priority	MELD = transplant. Child-Pugh = prognosis/surgery. Do NOT confuse.

Compensated cirrhosis: No complications. Median survival ~12 years.
Decompensated cirrhosis: Ascites, variceal hemorrhage, hepatic encephalopathy, or jaundice. Median survival ~2 years.

Ascites Management

Diagnostic paracentesis on ALL new-onset ascites — rule out SBP, malignancy, other cause
SAAG ≥1.1 g/dL: Portal hypertension (cirrhosis, CHF, Budd-Chiari)
SAAG <1.1 g/dL: Non-portal hypertension (malignancy, TB, nephrotic syndrome, pancreatitis)
Sodium restriction: 2 g/day
Diuretics: Spironolactone 100 mg + Furosemide 40 mg daily (100:40 ratio to maintain K⁺ balance). Titrate to max spironolactone 400 mg + furosemide 160 mg.
Large-volume paracentesis (LVP): For tense/symptomatic ascites. Give albumin 6–8 g per liter removed if >5 liters drained (prevents post-paracentesis circulatory dysfunction)
TIPS: For refractory ascites (failed maximum diuretics)

Spontaneous Bacterial Peritonitis (SBP)

⚑ SBP — "250 and Treat"

Diagnosis: Ascitic fluid PMN count ≥250 cells/mm³ → start antibiotics IMMEDIATELY. Do NOT wait for culture results.
Treatment: IV ceftriaxone 2g daily (or cefotaxime 2g q8h) × 5 days
Albumin is MANDATORY: 1.5 g/kg IV on Day 1 + 1 g/kg IV on Day 3 → reduces mortality from 41% to 22%, prevents hepatorenal syndrome
Secondary prophylaxis: Lifelong daily antibiotics after first SBP — TMP-SMX DS or ciprofloxacin 500 mg

Hepatic Encephalopathy (HE)

Precipitants (HEPATICS): Hemorrhage (GI bleed), Electrolytes, Protein excess, Azotemia, Tranquilizers/sedatives, Infection/SBP, Constipation, Surgery/shunts
Lactulose (first-line): 60 mL initially → 20 mL q1–2h until BM → titrate to 2–3 soft stools/day. Mechanism: acidifies colon → converts NH₃ to NH₄⁺ (non-absorbable) → ↓ ammonia absorption
Rifaximin 550 mg BID: Added for secondary prophylaxis after acute episode. Reduces recurrence ~50%. NOT first-line for acute HE.
Protein restriction is NO LONGER recommended — adequate protein intake 1.2–1.5 g/kg/day prevents sarcopenia, which WORSENS HE

Hepatorenal Syndrome (HRS)

Definition: Functional renal failure in advanced cirrhosis — splanchnic vasodilation → renal vasoconstriction → AKI
Diagnosis: AKI in cirrhosis after excluding other causes + no improvement after 2-day albumin challenge (1 g/kg/day × 2 days) + diuretic withdrawal
Treatment: IV albumin + vasoconstrictors (terlipressin preferred; or norepinephrine; or midodrine + octreotide)
Definitive treatment: Liver transplantation

⚑ Board Traps — Cirrhosis Complications

SAAG ≥1.1 = portal hypertension — replaces old transudate/exudate classification for ascites. This is SAAG, not total protein.
Spironolactone:furosemide ratio is 100:40 — maintains potassium balance. Do NOT use furosemide alone in cirrhotic ascites (hypokalemia → worsens HE).
Albumin is NOT optional in SBP — combined antibiotics + albumin reduces mortality and prevents HRS
Lactulose first for acute HE; rifaximin added for secondary prophylaxis — do NOT use rifaximin alone as first-line for acute episode
Protein restriction worsens HE by causing sarcopenia — outdated teaching. Protein 1.2–1.5 g/kg/day is required.
MELD ≠ Child-Pugh: MELD = transplant priority. Child-Pugh = surgical risk and prognosis.

★ Memory Trick

SAAG "≥1.1 = Portal HTN" — "High SAAG = High portal pressure" SBP: "250 and Treat" — PMN ≥250 = antibiotics now + albumin (mandatory) Diuretic ratio: "100:40 Spiro:Lasix" — the 5:2 ratio keeps potassium happy Child-Pugh "ABCDE": Albumin, Bilirubin, Coagulation, Distension, Encephalopathy Hepatic encephalopathy precipitants: "HEPATICS"

Clinical Vignette

A 58-year-old man with alcoholic cirrhosis is admitted with fever and abdominal pain. Diagnostic paracentesis shows PMN count of 380 cells/mm³. Cultures are pending.

Answer: SBP — PMN ≥250 = treat NOW, do not wait for cultures. Start IV ceftriaxone 2g daily. Give albumin 1.5 g/kg IV today and 1 g/kg on day 3 (reduces mortality from 41% to 22% and prevents HRS). After recovery, start lifelong SBP prophylaxis with daily TMP-SMX or ciprofloxacin.

Tier 1

Topic 6

Hepatitis B Serology

All 5 Markers · Window Period · Vaccinated vs Immune · Chronic vs Acute

★★★ PANCE PriorityWindow Period Trap

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The 5 Serologic Markers — What Each Means

Marker	What It Represents	Present When?
HBsAg	Surface antigen — hallmark of active infection	Acute AND chronic HBV; positive before symptoms
Anti-HBs	Surface antibody — immunity	After vaccination (alone) OR after resolved natural infection (with anti-HBc)
Anti-HBc IgM	Core IgM — acute infection marker	Acute HBV AND window period — the key marker in window period
Anti-HBc IgG (total anti-HBc)	Core IgG — prior exposure (persists for life)	Resolved infection, chronic HBV, or window period — never after vaccination
HBeAg	e-antigen — active viral replication, high infectivity	Acute and high-replication chronic HBV

Serology Interpretation Table — Memorize This

Status	HBsAg	Anti-HBs	Anti-HBc IgM	Anti-HBc IgG	HBeAg
Acute HBV	+	−	+	+	+
Window Period	−	−	+ (ONLY marker)	+	−
Chronic HBV	+	−	−	+	± (varies)
Resolved / Immune (natural infection)	−	+	−	+	−
Vaccinated only (no prior infection)	−	+ (ONLY marker)	−	−	−
Isolated anti-HBc positive	−	−	−	+	−

⚑ Board Traps — Hepatitis B Serology

Vaccinated = anti-HBs ONLY — no anti-HBc, no HBsAg. If anti-HBc is also positive, patient had NATURAL infection (not just vaccination)
Window period = only anti-HBc IgM is positive — HBsAg has disappeared, anti-HBs not yet appeared. Miss this marker = miss the diagnosis.
Serology does NOT confirm active infection — anti-HBc IgG alone means prior exposure. Only HBsAg confirms active infection.
Isolated anti-HBc positive: Most commonly resolved infection with lost anti-HBs; less commonly false positive, window period, or occult HBV. Check HBV DNA to clarify.
HBeAg positive = high infectivity — contagious to sexual partners, healthcare workers

★ Memory Trick

Vaccinated: "Anti-HBs ALONE — like a solo vaccine badge" Window period: "Anti-HBc IgM is the ONLY window you can see through" Resolved natural infection: "Anti-HBs + Anti-HBc = Been there, beat it" Chronic: "HBsAg stays positive, IgM is gone, IgG stays" "If anti-HBc is positive, the patient touched real virus (not just vaccine)"

Tier 1

Topic 7

Liver Enzyme Patterns & Acetaminophen Toxicity

AST:ALT Ratios · Cholestatic Pattern · GGT Trick · NAC Timing

★★★ PANCE PriorityNAC Timing Trap

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Liver Enzyme Pattern Recognition

Pattern	Enzymes Elevated	Causes	Board Key
Hepatocellular	AST + ALT predominant (high > 2–3× ALP)	Viral hepatitis, drug-induced (APAP), ischemic hepatitis, autoimmune, alcohol	AST:ALT >2:1 = Alcoholic liver disease. AST almost NEVER >300 in alcohol alone.
Cholestatic	ALP + GGT predominant (> 3× normal)	Choledocholithiasis, malignancy, PBC (AMA+), PSC (p-ANCA+, UC assoc.), drug-induced	Elevated ALP — confirm hepatic origin with GGT. If GGT normal → bone source (Paget's, bone mets).
Massive elevation (AST/ALT >1000)	Both dramatically elevated	Acute viral hepatitis, acetaminophen toxicity, ischemic hepatitis ("shock liver"), autoimmune hepatitis	AST/ALT >1000 = NOT alcohol. Think APAP, viral, ischemia, autoimmune.
Alcoholic hepatitis	AST:ALT >2:1 (typically 2–5:1)	Alcohol — mitochondrial AST release	AST almost NEVER >300 in alcoholic hepatitis. If AST >300, consider another diagnosis.

Acetaminophen (APAP) Toxicity

Most common cause of acute liver failure in the US
Toxic dose: 150 mg/kg or 7.5g in adults (lower threshold with chronic alcohol use, fasting, CYP-inducing drugs)
Mechanism: NAPQI (toxic metabolite via CYP2E1) depletes glutathione → hepatocellular necrosis
Antidote: N-acetylcysteine (NAC) — replenishes glutathione, neutralizes NAPQI
NAC timing: Most effective within 8 hours of ingestion. BUT beneficial up to 72 hours — give even if delayed presentation
Rumack-Matthew nomogram: Plot serum APAP level at ≥4 hours post-ingestion to determine NAC need
Clinical stages: Stage 1 (0–24h): N/V, malaise. Stage 2 (24–72h): RUQ pain, LFTs rise. Stage 3 (72–96h): Peak hepatotoxicity, possible fulminant failure. Stage 4: Recovery or death.

⚑ Board Traps — Liver Labs

Alcoholic hepatitis: AST almost never >300 — if AST >300, think viral hepatitis, APAP, ischemia, or autoimmune
Elevated ALP → check GGT — GGT elevated confirms hepatic origin. Normal GGT = bone source (not liver)
PSC is associated with UC, not Crohn's — and with p-ANCA positive serology
PBC is associated with anti-mitochondrial antibody (AMA) — middle-aged women with pruritus and elevated ALP
NAC is the answer for APAP toxicity — give even if presentation is delayed (>8 hours). Do not withhold because of late presentation.
Ischemic hepatitis ("shock liver"): Dramatic AST/ALT elevation (often >3000) after hypotensive episode — improves rapidly with hemodynamic recovery

★ Memory Trick

AST:ALT "2:1 rule" = Alcohol (AST twice ALT, both usually <300) "If AST >300 in a drinker — rethink the diagnosis" ALP elevated: "G-check first" — if GGT is normal, it's BONE not LIVER APAP antidote: "NAC = N-AcetylCysteine = Natural GLUTathione precursor" NAC timing: "Best before 8 hours, helpful up to 72 — never too late to give"

Domain 3 · Lower GI Disorders

Lower GI — IBD, Colorectal Cancer, Diverticular Disease

Tier 1

Topic 8 ★ Gap Added

Lower GI Bleeding

Diverticular · Angiodysplasia · LGIB vs UGIB Distinction · Colonoscopy Timing

★★ High YieldGap Topic

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Core Recognition Pattern

LGIB presents as: Hematochezia (bright red or maroon blood per rectum) — blood below ligament of Treitz
Most common causes in adults: Diverticular disease (#1 in adults >40), angiodysplasia (#2), internal hemorrhoids (most common cause in young adults), colorectal cancer, ischemic colitis, IBD
Rule out UGIB first: Massive UGIB can present with hematochezia — if hemodynamically unstable with bright red blood, insert NGT or perform upper endoscopy first

Key Differentials

Cause	Classic Patient	Key Feature	Definitive Dx
Diverticular bleed	Elderly, constipated, painless	Painless, large volume, self-limited 80%. Usually right-sided diverticula bleed despite left-sided prevalence.	Colonoscopy (after prep)
Angiodysplasia	Elderly, chronic kidney disease, aortic stenosis	Recurrent small-volume bleeds. Heyde syndrome: AS + angiodysplasia + acquired vWF deficiency	Colonoscopy — telangiectasias in cecum/right colon
Hemorrhoids	Young adults, constipation, straining	Bright red blood on tissue, not mixed in stool. Painless (internal) vs. painful (external/thrombosed)	Anoscopy / sigmoidoscopy
Ischemic colitis	Elderly, atherosclerosis, post-vascular surgery	Crampy abdominal pain + bloody diarrhea. Watershed areas: splenic flexure, sigmoid	CT abdomen + colonoscopy
Colorectal cancer	Age >45, iron deficiency anemia, weight loss	Change in bowel habits, positive FOBT, occult bleeding	Colonoscopy + biopsy

Management

Resuscitation first: IV access, CBC, type and screen, restrictive transfusion strategy (Hgb <7)
Colonoscopy: Gold standard for diagnosis AND treatment (within 24 hours for hemodynamically stable; within 8–12 hours for active bleeding after prep)
CT angiography: If active bleeding rate >0.5 mL/min — identifies bleeding site for IR embolization
Angiographic embolization (IR): For active bleeding when colonoscopy fails or patient too unstable
Surgery: Last resort — segmental colectomy if all endoscopic/IR options fail

⚑ Board Traps — LGIB

Diverticular bleeding is usually PAINLESS — pain suggests diverticulitis or ischemic colitis instead
Most diverticular bleeds (80%) stop spontaneously — aggressive endoscopic intervention not always required
Heyde syndrome: Aortic stenosis + gastrointestinal angiodysplasia + acquired von Willebrand disease — the triad. AVR resolves the bleeding tendency.
Ischemic colitis: treat conservatively (bowel rest, IV fluids, antibiotics) unless peritonitis or perforation — then surgery

Tier 1

Topic 9

Inflammatory Bowel Disease

Crohn vs UC · Extraintestinal Manifestations · Biologics · Surgical Indications

★★★ PANCE PriorityMany Traps

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Crohn vs UC — The Core Comparison

Feature	Crohn Disease	Ulcerative Colitis
Location	Mouth to anus — terminal ileum + colon most common	Colon ONLY — starts at rectum, extends proximally
Pattern	Skip lesions (discontinuous), transmural	Continuous, circumferential, mucosal/submucosal only
Rectal involvement	Rectal sparing is classic	Rectum always involved
Endoscopy	Cobblestoning, aphthous ulcers, linear ulcers	Erythema, friability, pseudopolyps, lead-pipe colon
Histology	Non-caseating granulomas (30% of biopsies)	Crypt abscesses, architectural distortion
Key complications	Fistulas, strictures, abscesses, B12 deficiency (terminal ileum)	Toxic megacolon, massive hemorrhage, colorectal cancer (after 8–10 years pancolitis)
Surgery	Not curative — disease recurs	Total colectomy = curative
Smoking	Worsens Crohn	Protective in UC (NOT a treatment recommendation)
PSC association	Not associated	PSC strongly associated with UC

Extraintestinal Manifestations

Manifestation	Correlates with Disease Activity?	Association
Peripheral arthritis	YES — flares with bowel activity	Both
Erythema nodosum	YES — flares with bowel activity	Both (more Crohn)
Ankylosing spondylitis / sacroiliitis	NO — independent of bowel activity	Both
Pyoderma gangrenosum	NO — independent of bowel activity	Both (more UC)
Primary sclerosing cholangitis (PSC)	NO — independent	UC strongly (not Crohn)
Uveitis / episcleritis	Variable	Both

Treatment Algorithm

Mild disease: 5-ASA (mesalamine) — effective in UC; limited role in Crohn (do NOT use as Crohn monotherapy)
Moderate-severe disease (induction): Corticosteroids (prednisone, budesonide) — induction ONLY, never maintenance
Maintenance / Moderate-severe: Biologics or small molecules (see table below)
Immunomodulators: Azathioprine, 6-MP (TPMT/NUDT15 testing required before initiation), methotrexate (Crohn)

Drug Class	Examples	Key Notes
Anti-TNF	Infliximab, Adalimumab, Certolizumab (Crohn), Golimumab (UC)	Screen for TB (PPD/IGRA) and Hepatitis B before starting — risk of reactivation
Anti-integrin	Vedolizumab	Gut-selective — lower systemic infection risk
Anti-IL-12/23	Ustekinumab	Both Crohn and UC
Anti-IL-23	Risankizumab, Mirikizumab	Newer agents
JAK inhibitors	Tofacitinib, Upadacitinib	UC. Risk: VTE, infections, malignancy — black box warning
S1P modulator	Ozanimod	UC. Cardiac monitoring required (bradycardia on initiation)

Toxic Megacolon — Emergency

Definition: Colonic dilatation >6 cm (transverse colon) + systemic toxicity (fever, tachycardia, leukocytosis, hypotension)
Causes: Severe UC, Crohn, C. diff colitis, CMV colitis
Management: NPO, IV steroids, IV antibiotics, surgical consultation. Avoid antidiarrheals, opioids, anticholinergics — precipitate or worsen toxic megacolon.
If no improvement in 24–72 hours → emergency colectomy

⚑ Board Traps — IBD

PSC is associated with UC, NOT Crohn — PSC increases risk of cholangiocarcinoma. PSC + UC = annual colonoscopy (high CRC risk).
5-ASA (mesalamine) works in UC, NOT Crohn as monotherapy — commonly tested distractor
Steroids for induction ONLY — never maintenance. Long-term steroids = osteoporosis, DM, adrenal suppression, infection
Check TPMT/NUDT15 before azathioprine/6-MP — enzyme deficiency → severe myelosuppression
Anti-TNF agents: screen for TB and Hepatitis B first — reactivation risk
Total colectomy is curative for UC but NOT for Crohn — disease recurs in Crohn at anastomotic sites
Antidiarrheals and opioids in severe colitis = contraindicated — precipitate toxic megacolon

★ Memory Trick

Crohn: "Anything Goes — Mouth to anus, Skip lesions, Transmural, Fistulas, B12 deficient" UC: "Starts at the Rectum, Continuous up, Bloody, Curable (colectomy), PSC" PSC: "PSC = UC's companion — never Crohn's" Extraintestinal: Correlates with activity: Peripheral arthritis, Erythema nodosum Does NOT correlate: Ankylosing spondylitis, Pyoderma gangrenosum, PSC, Uveitis "APEPU" — Activity-independent manifestations: Ankylosing spondylitis, PSC, Episcleritis, Pyoderma, Uveitis

Tier 1

Topic 10 ★ Gap Added

Colorectal Cancer Screening & Surveillance

USPSTF Guidelines · Screening Intervals · IBD Surveillance · Lynch Syndrome

★★★ PANCE PriorityGap TopicInterval Traps

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Why the PANCE Tests This Every Exam

Colorectal cancer is the #2 cause of cancer death in the US. The PANCE tests screening start age, intervals for different test types, surveillance after polyp removal, and high-risk populations. These are pure memorization questions — know the numbers cold.

Average-Risk Screening — USPSTF 2021 Guidelines

Test	Start Age	Interval	Board Key
Colonoscopy	45 years	Every 10 years	Gold standard — diagnostic AND therapeutic
Annual FOBT (high-sensitivity guaiac)	45 years	Every year	If positive → colonoscopy required
Annual FIT (fecal immunochemical test)	45 years	Every year	More sensitive than guaiac FOBT for CRC
Stool DNA (Cologuard)	45 years	Every 1–3 years	If positive → colonoscopy required
CT colonography (virtual colonoscopy)	45 years	Every 5 years	If polyp found → colonoscopy needed
Flexible sigmoidoscopy	45 years	Every 5 years (or every 10 years + annual FIT)	Only examines left colon
STOP screening	75 years (individualize 76–85)	—	Discontinue at 75 per USPSTF unless patient request and good health

Colonoscopy Surveillance After Polyp Removal

Finding at Colonoscopy	Surveillance Interval
No polyps (normal colonoscopy)	10 years
1–2 small (<10mm) tubular adenomas	7–10 years
3–4 small tubular adenomas	3–5 years
5+ tubular adenomas OR any adenoma ≥10mm	3 years
Any villous/tubulovillous adenoma OR high-grade dysplasia	3 years
Sessile serrated polyp <10mm, no dysplasia	5 years
Sessile serrated polyp ≥10mm OR with dysplasia	3 years

High-Risk Populations — Earlier / More Frequent Screening

Risk Factor	Start Screening	Interval
First-degree relative with CRC or advanced adenoma <60 years	40 years OR 10 years before relative's diagnosis	Every 5 years
Ulcerative colitis (pancolitis) or Crohn colitis	8–10 years after diagnosis	Every 1–2 years
UC + PSC	At diagnosis of PSC	Annual
Familial adenomatous polyposis (FAP)	Age 10–15 with flexible sigmoidoscopy	Annual
Lynch syndrome (HNPCC) — MLH1, MSH2, MSH6, PMS2 mutations	Age 20–25	Every 1–2 years

⚑ Board Traps — CRC Screening

USPSTF 2021: screening now starts at age 45 (changed from 50 in 2021) — older questions may say 50, but current answer is 45
Positive stool test always requires colonoscopy — FOBT/FIT/Cologuard are not diagnostic; colonoscopy is needed for any positive result
UC surveillance starts 8–10 years after pancolitis diagnosis — NOT at diagnosis
Lynch syndrome patients start colonoscopy at 20–25 — most aggressive surveillance schedule
Villous adenomas and high-grade dysplasia: 3-year surveillance — high malignant potential

★ Memory Trick

Average-risk screening: "Start at 45, colonoscopy every 10, FOBT/FIT every year" Surveillance after polyps: "More polyps or bigger polyps = shorter surveillance interval" 1–2 small adenomas → 7–10 years ("Just a few, see you later") 5+ or ≥10mm → 3 years ("High risk, see you soon") Lynch syndrome: "Start Early at 20–25, see every 1–2 years — genes are aggressive" UC colitis surveillance: "8–10 years to get started, then every 1–2 years"

Domain 4 · Pancreas & Biliary Tract

Pancreatitis, Biliary Disease & Celiac

Tier 1

Topic 11

Acute Pancreatitis

Revised Atlanta Criteria · I GET SMASHED · Early Feeding · Biliary Pancreatitis

★★★ PANCE PriorityNPO Trap · CT Trap

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Diagnosis — Revised Atlanta Criteria (2 of 3)

1. Acute onset severe epigastric pain radiating to the back
2. Serum lipase (or amylase) ≥3× upper limit of normal
3. Characteristic findings on CT or MRI

~80% diagnosed on criteria 1+2 alone — CT not required for every patient at admission.

Etiology — "I GET SMASHED"

Causes in Order of Frequency

Idiopathic · Gallstones (#1 cause ~40%) · Ethanol (#2 cause ~25%) · Trauma
Steroids · Mumps/Malignancy · Autoimmune · Scorpion stings
Hyperlipidemia (TG >1000), Hypercalcemia, Hypothermia · ERCP · Drugs (valproate, azathioprine, furosemide, TMP-SMX, didanosine)

Severity — Revised Atlanta Classification

Severity	Definition	Mortality	Management
Mild (~80%)	No organ failure, no local complications	<1%	IVF, pain control, early feeding — most discharge within days
Moderately Severe	Transient organ failure (<48h) and/or local complications	~8%	Monitoring, IVF, nutrition support if not eating in 5–7 days
Severe	Persistent organ failure (>48h)	20–40%	ICU admission, early enteral nutrition, +/- ERCP if cholangitis

BISAP Score: BUN >25, Impaired mental status, SIRS, Age >60, Pleural effusion — ≥3 predicts severe disease within 24h (better than Ranson's, which requires 48h to complete)

Management

IV fluids: Lactated Ringer's preferred over normal saline. Goal-directed resuscitation (250–500 mL/hr initially). Avoid over-resuscitation (WATERFALL trial).
Pain: IV opioids (hydromorphone, fentanyl). Meperidine is NO longer preferred — no proven benefit over other opioids re: sphincter of Oddi spasm.
Early oral feeding: Feed as soon as patient can tolerate — DO NOT keep NPO unnecessarily. Early feeding (within 24 hours if tolerated) improves outcomes.
If oral intake not tolerated: Enteral nutrition (nasogastric or nasojejunal) is preferred over parenteral nutrition. Enteral > TPN.
Antibiotics: NOT indicated prophylactically for sterile pancreatitis. Reserve for infected necrosis (fever + CT showing gas in necrosis).

Biliary Pancreatitis — Special Considerations

Mild biliary pancreatitis: Cholecystectomy during the SAME admission (prevents recurrence — 25–30% recurrence without same-admission CCY)
ERCP indication in pancreatitis: Only if concurrent cholangitis (fever + jaundice + RUQ pain = Charcot's triad) or persistent biliary obstruction — NOT routinely for uncomplicated biliary pancreatitis
Severe biliary pancreatitis: Delay cholecystectomy until recovery — interval CCY 4–8 weeks

⚑ Board Traps — Acute Pancreatitis

Lipase > amylase — lipase is more sensitive AND specific; also stays elevated longer (8–14 days vs 3–5 days for amylase)
CT is NOT required at admission for most patients — only for diagnostic uncertainty or suspected complications (72–96h)
Early oral feeding is now standard — "NPO until pain resolves" is OUTDATED teaching. Feed when patient can tolerate it.
Enteral > Parenteral nutrition — gut integrity is maintained, fewer infections, shorter hospitalization
Meperidine is NOT preferred over other opioids — old teaching was that it causes less sphincter of Oddi spasm, but this is not supported by evidence
Ranson criteria requires 48 hours to complete — cannot be scored at admission. Use BISAP (calculable within 24h)
Prophylactic antibiotics in pancreatitis = NOT indicated for sterile necrosis. Only treat confirmed infected necrosis.
Same-admission cholecystectomy for mild biliary pancreatitis — prevents 25–30% recurrence

★ Memory Trick

Diagnosis: "2 of 3 Atlanta criteria" — pain + lipase ≥3× + imaging (usually 2 out of 3 is enough) Etiology: "I GET SMASHED" — Gallstones #1, Ethanol #2 Severity: "Mild = No organ failure, Severe = >48h organ failure" Nutrition: "Feed early, no TPN — the gut knows what to do" Biliary pancreatitis: "Fix the gallbladder same visit for mild disease" BISAP: "BUS-APE" — BUN, Impaired mental, SIRS, Age, Pleural effusion

Clinical Vignette

A 48-year-old woman presents with acute epigastric pain radiating to her back, nausea, and vomiting after a fatty meal. Lipase is 1850 U/L (normal <60). Ultrasound shows gallstones. No fever. Bilirubin is normal. She is admitted and kept NPO with IV morphine. By day 2 she is hungry and tolerating liquids.

Answer: Mild biliary pancreatitis. Start oral diet now — do NOT keep NPO when she can tolerate intake. Plan same-admission cholecystectomy before discharge (prevents 25–30% recurrence). No ERCP needed (no cholangitis, no persistent obstruction). No CT needed (diagnosis confirmed clinically). Switch from morphine to oral pain management as tolerated.

Tier 1

Topic 12 ★ Gap Added

Biliary Tract Disease

Cholelithiasis · Cholecystitis · Choledocholithiasis · Cholangitis · Tokyo Criteria

★★★ PANCE PriorityGap TopicCharcot/Tokyo Traps

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The Biliary Spectrum — One Continuum

Condition	Where	Classic Presentation	Key Diagnostic	Treatment
Cholelithiasis	Gallbladder (stones)	Asymptomatic (80%). Biliary colic: RUQ pain 30 min–6h after fatty meal, no fever	Ultrasound (first-line)	Elective laparoscopic CCY if symptomatic
Acute Cholecystitis	Gallbladder wall inflammation	RUQ pain >6h + fever + Murphy sign positive. Leukocytosis.	US (thickened wall, pericholecystic fluid, sonographic Murphy sign). HIDA if US unclear.	IV antibiotics + urgent CCY (within 72h preferred)
Choledocholithiasis	Common bile duct (stone)	RUQ pain + jaundice + elevated LFTs (biliary pattern)	US → MRCP (gold standard noninvasive) or EUS	ERCP with sphincterotomy + stone removal, then CCY
Acute Cholangitis	Bile duct infection	Charcot's triad: RUQ pain + Fever/chills + Jaundice (67% of cases). Reynolds pentad: + AMS + Hypotension (severe)	LFTs (cholestatic), blood cultures, US or CT	IV antibiotics + emergent ERCP for biliary decompression

Murphy Sign vs. Sonographic Murphy Sign

Murphy sign: Palpation of RUQ during deep inspiration → patient stops breathing due to pain — sensitivity ~65%, specificity ~87%
Sonographic Murphy sign: Transducer-elicited pain directly over the gallbladder — more specific when combined with gallbladder wall thickening >3mm

Tokyo Guidelines — Cholangitis Severity

Grade	Definition	Management
Grade I (Mild)	Responds to antibiotics alone	IV antibiotics, elective ERCP within 48–72 hours
Grade II (Moderate)	No organ dysfunction but not improving with antibiotics alone	IV antibiotics + early ERCP (within 24–48 hours)
Grade III (Severe)	Organ dysfunction (Reynolds pentad — AMS, hypotension)	IV antibiotics + emergent ERCP or biliary drainage within hours

Acalculous Cholecystitis

Occurs without gallstones — critically ill patients (ICU, post-surgery, burns, TPN, sepsis, trauma)
Mechanism: Bile stasis + ischemia → gallbladder wall inflammation
Diagnosis: US or HIDA scan. CT if US inconclusive.
Treatment: Percutaneous cholecystostomy (drainage) if too unstable for surgery. Cholecystectomy when stable.

⚑ Board Traps — Biliary Disease

Biliary colic is RUQ pain lasting 30 min–6 hours — if >6 hours, think cholecystitis
Murphy sign is NOT specific for cholecystitis — also positive in hepatitis. Use in combination with fever and leukocytosis.
ERCP is NOT the first-line test for choledocholithiasis — MRCP or EUS first (noninvasive), then therapeutic ERCP
Reynolds pentad = Charcot's triad + AMS + hypotension = severe ascending cholangitis = EMERGENT biliary decompression
Acalculous cholecystitis in ICU patients: No stones — think of it in any ICU patient with unexplained fever + RUQ tenderness
Choledocholithiasis: ERCP + stone removal first, THEN cholecystectomy — not simultaneous

★ Memory Trick

Biliary spectrum: "Stones → Wall → Duct → Duct+Infection" Cholecystitis timing: "Colic <6h, Cholecystitis >6h" Charcot's triad: "Pain + Fever + Jaundice = Charcot" (think Charlotte's 3 traits) Reynolds pentad: "Charcot + SHOCK (AMS + Hypotension) = Emergency ERCP now" ERCP: "Fix the duct first (ERCP), then fix the bag (CCY)" Acalculous: "No stones? Check for it in the ICU patient with fever"

Tier 2

Topic 13 ★ Gap Added

Celiac Disease (Gluten-Sensitive Enteropathy)

Anti-tTG IgA · Villous Atrophy · Gluten-Free Diet · Associated Conditions

★★ High YieldGap TopicDiet Trap

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Core Recognition

Pathophysiology: Immune-mediated reaction to gliadin (wheat), secalin (rye), hordein (barley) → small bowel villous atrophy → malabsorption
Classic (GI) presentation: Chronic diarrhea, bloating, weight loss, steatorrhea, abdominal distension. Often triggered by pregnancy, GI infection, or surgery.
Atypical (non-GI) presentation: Iron deficiency anemia (most common cause of celiac diagnosis), osteoporosis, dermatitis herpetiformis (pruritic vesicular rash on extensor surfaces), unexplained infertility, elevated liver enzymes, peripheral neuropathy
Associated conditions: Type 1 diabetes, Down syndrome, Turner syndrome, autoimmune thyroid disease, IgA deficiency

Diagnostic Approach

First test: Anti-tissue transglutaminase IgA (anti-tTG IgA) — most sensitive and specific serologic test
Check total IgA level simultaneously — IgA deficiency (~2% of celiac patients) causes false-negative anti-tTG IgA; use IgG-based tests if IgA deficient
Gold standard: Upper endoscopy with small bowel biopsy (duodenum) — shows villous atrophy, crypt hyperplasia, increased intraepithelial lymphocytes
Patient must be on a gluten-containing diet at time of testing — gluten-free diet normalizes serology and histology, creating false negatives
Anti-endomysial antibody (EMA-IgA): Also specific; used when anti-tTG is equivocal

Treatment

Strict lifelong gluten-free diet (GFD) — wheat, rye, barley must be completely eliminated
Oats: Most celiacs can tolerate pure (uncontaminated) oats — but avoid due to cross-contamination risk
Monitor response: Repeat anti-tTG IgA at 6–12 months to confirm dietary adherence
Supplementation: Iron, folate, calcium, vitamin D, B12 — correct deficiencies
Refractory celiac disease: Symptoms persist despite strict GFD — rule out inadvertent gluten exposure first; then consider immunosuppression

⚑ Board Traps — Celiac

Do NOT start gluten-free diet before testing — serology and biopsy will be falsely negative. Must test while on gluten.
Check total IgA with anti-tTG IgA — IgA deficiency causes false-negative results
Dermatitis herpetiformis = celiac skin manifestation — pruritic vesicular rash on extensor surfaces (elbows, knees, buttocks). Treat with GFD + dapsone.
Iron deficiency anemia is the most common initial presentation in adults — think celiac in any patient with unexplained iron deficiency
Celiac + Type 1 DM: Screen all T1DM patients for celiac (anti-tTG IgA)
Increased risk of: T-cell lymphoma (enteropathy-associated), small bowel adenocarcinoma — in uncontrolled or refractory celiac

★ Memory Trick

Celiac serology: "anti-tTG IgA = first test, always check total IgA alongside" "Must eat gluten to detect gluten disease — test BEFORE the diet" Dermatitis herpetiformis: "Blistery elbows and knees = Celiac skin" "Iron deficiency + diarrhea + young adult = think Celiac first" Associated conditions: "Down, Turner, T1DM, autoimmune thyroid = screen for Celiac"

Tier 2

Topic 14

Chronic Pancreatitis

Triad · Exocrine Insufficiency · CREON · Pancreatic Cancer Risk

★ Important

🔒 Full content available with bootcamp enrollment. Get access →

Core Recognition

Classic triad: Epigastric pain radiating to back + steatorrhea (fat malabsorption) + diabetes mellitus
Most common cause: Chronic alcohol use (~70%). Also: idiopathic, hereditary (PRSS1 mutation), autoimmune, obstruction.
Imaging: Pancreatic calcifications on plain X-ray or CT (pathognomonic). Ductal dilation on MRCP/ERCP.
Diagnosis: Fecal elastase-1 level (low = exocrine insufficiency). CT or MRCP for structural assessment.

Treatment

Alcohol cessation (most important modifiable factor)
Pain management: Analgesics → celiac plexus block → surgical decompression if ductal dilation
Pancreatic enzyme replacement (CREON): For exocrine insufficiency with steatorrhea — take WITH meals
Fat-soluble vitamin supplementation: A, D, E, K
Diabetes management: "Brittle" pancreatic DM — very sensitive to insulin, monitor carefully
Pancreatic cancer screening: Risk factor — screen with EUS or MRI annually if chronic pancreatitis + hereditary factors or PRSS1 mutation

⚑ Board Traps — Chronic Pancreatitis

Pancreatic calcifications on X-ray = diagnostic of chronic pancreatitis — specific finding
Lipase and amylase may be NORMAL in chronic pancreatitis — burned-out gland with little functional tissue remaining
Pancreatic enzyme replacement must be taken WITH meals — not before or after
Increased risk of pancreatic adenocarcinoma — especially with hereditary chronic pancreatitis

Tier 1

Topic 15 ★ Gap Added

Irritable Bowel Syndrome (IBS)

Rome IV Criteria · Positive Diagnosis · NOT Exclusion · Subtypes · Treatment

★★ High YieldGap TopicDiagnosis Trap

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Why the PANCE Tests This

IBS is the most common GI diagnosis in outpatient practice (~15% of adults). Boards specifically test the Rome IV criteria, the paradigm shift that IBS is a positive diagnosis (not exclusion), subtype-based treatment, and alarm symptoms that require workup before diagnosing IBS.

Core Recognition Pattern — Rome IV Criteria

Rome IV Diagnostic Criteria (all 3 required)

Recurrent abdominal pain ≥1 day/week in the last 3 months, associated with ≥2 of the following:
Related to defecation (pain improves OR worsens with bowel movement)
Associated with a change in stool frequency
Associated with a change in stool form/appearance
Symptoms present for ≥6 months before diagnosis

IBS Subtypes

Subtype	Stool Pattern	First-Line Treatment
IBS-C (Constipation-predominant)	>25% hard/lumpy stools, <25% loose	Soluble fiber (psyllium), lubiprostone, linaclotide, plecanatide, polyethylene glycol
IBS-D (Diarrhea-predominant)	>25% loose/watery stools, <25% hard	Loperamide (symptom control), rifaximin (non-absorbable antibiotic), alosetron (women only — restricted use)
IBS-M (Mixed)	Both patterns >25%	Target predominant symptom; peppermint oil for global symptom relief
IBS-U (Unsubtyped)	Insufficient abnormal stool	Symptomatic management

Alarm Symptoms Requiring Workup Before IBS Diagnosis

Age >45 with new symptoms — colonoscopy to rule out colorectal cancer
Unintentional weight loss
Rectal bleeding or iron deficiency anemia
Nocturnal symptoms — IBS does NOT wake patients from sleep (functional disorders respect sleep)
Family history of CRC, IBD, or celiac disease
Fever
Inflammatory markers elevated (elevated CRP, fecal calprotectin) — suggests IBD, not IBS

Treatment Overview

Lifestyle first: Low-FODMAP diet (fermentable oligosaccharides, disaccharides, monosaccharides, polyols) — reduces fermentation and gas. Most evidence-based dietary intervention for IBS.
Global symptom relief: Peppermint oil (antispasmodic), tricyclic antidepressants (low-dose — reduce visceral hypersensitivity), SSRIs (IBS-D)
IBS-D: Rifaximin (non-absorbable antibiotic) — 2-week course, reduces bloating and diarrhea. Can repeat if symptoms return.
IBS-C: Linaclotide or lubiprostone (secretagogues) — increase intestinal fluid secretion
Psychological interventions: CBT and gut-directed hypnotherapy — as effective as pharmacotherapy in many trials

⚑ Board Traps — IBS

IBS is a POSITIVE diagnosis based on Rome IV criteria — NOT a diagnosis of exclusion. This is a major paradigm shift. You do NOT need to rule out every other GI disease before diagnosing IBS in the absence of alarm features.
IBS does NOT cause nocturnal symptoms — abdominal pain or diarrhea that wakes the patient from sleep should prompt workup (IBD, microscopic colitis, malabsorption)
IBS does NOT cause rectal bleeding, weight loss, or anemia — these are alarm features requiring colonoscopy
Fecal calprotectin is elevated in IBD, NOT IBS — useful noninvasive test to differentiate IBS from IBD when colonoscopy not yet done
Alosetron (5-HT3 antagonist) for IBS-D in women: REMS program required due to risk of ischemic colitis and severe constipation — restricted use
Celiac disease should always be excluded in IBS-D — check anti-tTG IgA before labeling as IBS

★ Memory Trick

Rome IV: "Pain ≥1 day/week for 3+ months, with 2 of 3: Defecation, Frequency, Form changes" IBS is POSITIVE — not a trash-can diagnosis. "If Rome IV criteria met + no alarms = IBS. Done." "IBS does not wake you up" — nocturnal symptoms = organic disease Low-FODMAP: "Fermentable Oligo- Di- Mono-saccharides And Polyols" — cut these, calm the gut IBS-D drug: "Rifaximin clears the gut bugs (non-absorbable, safe, repeatable)"

Clinical Vignette

A 29-year-old woman has 8 months of crampy abdominal pain that is relieved by defecation, alternating loose and hard stools, and bloating. No weight loss, no blood in stool, no nocturnal symptoms. CBC, CMP, CRP, and TSH are normal. Anti-tTG IgA is negative.

Answer: IBS-M (Mixed subtype) — Rome IV criteria met (≥6 months, pain ≥1 day/week associated with defecation and change in stool form/frequency). No alarm features. Celiac excluded. This is a POSITIVE diagnosis — no colonoscopy required at this age without alarm features. Start low-FODMAP diet. Consider peppermint oil or low-dose TCA for global symptom control.

Tier 1

Topic 16 ★ Gap Added

Diverticular Disease

Diverticulosis · Diverticulitis · Antibiotics Paradigm Shift · Complications

★★ High YieldGap TopicGuideline Updated

🔒 Full content available with bootcamp enrollment. Get access →

Core Recognition Pattern

Diverticulosis: Outpouchings of colonic mucosa through weak points in the bowel wall. Present in ~70% of adults by age 80. Usually asymptomatic. Most common in sigmoid colon (left-sided in Western populations).
Diverticulitis: Inflammation/infection of a diverticulum. Classic presentation: LLQ pain + fever + leukocytosis. Nausea, anorexia, constipation or diarrhea. CT is gold standard for diagnosis.
Remember: Diverticular bleeding is usually right-sided (despite left-sided prevalence of diverticula) and is painless (covered in LGIB topic)

Hinchey Classification — Severity Staging

Stage	Finding	Management
I	Pericolic/mesenteric abscess	IV antibiotics ± percutaneous drainage if >3–4cm
II	Pelvic/retroperitoneal abscess	IV antibiotics + percutaneous drainage
III	Purulent peritonitis (generalized)	Emergency surgery
IV	Feculent peritonitis (gross fecal contamination)	Emergency surgery — highest mortality

Treatment — The Paradigm Shift

★ 2023 Guideline Update — Antibiotics NOT Routine

Uncomplicated acute diverticulitis (Hinchey Ia — mild, no abscess, no perforation, immunocompetent): Antibiotics are NOT routinely recommended. Multiple RCTs (AVOD, DIABOLO, DIVER trials) show antibiotics provide no benefit in uncomplicated disease.
Management of uncomplicated diverticulitis: Clear liquid diet, oral analgesics, outpatient management for mild cases.
Antibiotics ARE indicated for: Complicated diverticulitis (abscess, perforation, fistula), immunocompromised patients, significant comorbidities, failure to improve, systemic sepsis.
IV antibiotics (complicated/hospitalized): Ceftriaxone + metronidazole, or piperacillin-tazobactam, or ampicillin-sulbactam.

Key Management Points

CT abdomen/pelvis with IV contrast: Gold standard for diagnosis and severity staging. First-line imaging.
Outpatient treatment for mild uncomplicated diverticulitis: Clear liquids, analgesics, advance diet as tolerated. Follow-up in 48–72 hours.
Colonoscopy 6–8 weeks AFTER acute episode resolves: To rule out colorectal cancer masquerading as diverticulitis (and to screen if not recently done)
Elective sigmoid colectomy: After 2+ episodes of complicated diverticulitis, OR after 1 episode in immunocompromised patients. NOT after uncomplicated episodes alone.
Fistula formation: Colovesical fistula (most common) — pneumaturia and fecaluria. Colovaginal fistula — stool per vagina. Requires elective surgical repair.

Diverticulitis vs Diverticulosis vs Diverticular Bleed

Condition	Symptoms	Location	Key Management
Diverticulosis	Asymptomatic (most), cramping, bloating	Left colon (sigmoid)	High-fiber diet. No treatment needed for asymptomatic.
Diverticulitis	LLQ pain + fever + leukocytosis	Left colon (sigmoid inflammation)	Uncomplicated: diet + analgesia (no routine antibiotics). Complicated: antibiotics ± drainage ± surgery.
Diverticular bleed	Painless large-volume hematochezia	Right colon (bleeds despite left-sided diverticula)	80% self-limited. Colonoscopy for diagnosis/treatment. IR embolization or surgery if refractory.

⚑ Board Traps — Diverticular Disease

Uncomplicated diverticulitis does NOT require antibiotics — this is the major 2023 paradigm shift. RCTs (AVOD, DIABOLO, DIVER) show no benefit in immunocompetent patients with uncomplicated disease.
Diverticulitis presents with LLQ pain + fever — diverticular bleed is PAINLESS hematochezia. Do not confuse the two.
Colonoscopy after acute diverticulitis: Wait 6–8 weeks after resolution — colonoscopy during acute inflammation increases perforation risk.
Colovesical fistula: Pneumaturia (air in urine) + fecaluria = pathognomonic for colovesical fistula. Confirm with CT or cystoscopy. Elective surgical repair.
High-fiber diet reduces diverticulitis recurrence — encourage in all patients with diverticulosis. Old teaching that nuts/seeds/corn worsen diverticulitis has been disproven.
Perforation or generalized peritonitis = emergency surgery — no role for conservative management in Hinchey III/IV

★ Memory Trick

Diverticulitis = "Left Lower Quadrant + Fever + Leukocytosis" Diverticular bleed = "Painless + Large volume + Right colon (despite living on left)" Antibiotics in uncomplicated diverticulitis: "AVOD, DIABOLO, DIVER said NO — skip the ABx for mild disease" Fistula: "Pneumaturia = air in the urine = colovesical fistula = colon connected to bladder" Colonoscopy: "6–8 weeks to let the fire cool down before scoping"

Clinical Vignette

A 54-year-old man presents with 2 days of LLQ pain, low-grade fever of 38.1°C, and constipation. WBC is 13.2. CT abdomen shows sigmoid diverticulitis with pericolic fat stranding and no abscess or perforation. He is tolerating oral fluids and is not immunocompromised.

Answer: Uncomplicated acute diverticulitis (Hinchey Ia). Per current guidelines, antibiotics are NOT routinely required for uncomplicated diverticulitis in immunocompetent patients. Manage with clear liquid diet, advance as tolerated, oral analgesics, and close outpatient follow-up in 48–72 hours. Plan colonoscopy 6–8 weeks after resolution to exclude malignancy. If symptoms worsen or fail to improve in 48–72h, reassess and consider antibiotics.

Blueprint Gap Topics · Added 2025

Appendicitis · Hepatitis A & C · NAFLD/NASH · Hernias · Bowel Obstruction · Hemorrhoids & Anal Fissure

Topics present on the 2025 NCCPA PANCE Blueprint not covered in prior modules — now fully integrated

Appendicitis

Alvarado Score · CT vs Ultrasound · McBurney's Point · Perforation Risk · Surgical Timing · Antibiotics-First Debate

Why the PANCE Tests This

Appendicitis is the most common surgical emergency in the United States. The PANCE tests the classic presentation, imaging choice by patient population, Alvarado scoring, and complications (perforation, peritonitis, abscess).

Classic Presentation & Physical Exam Signs

Typical Progression

Begins as periumbilical pain → migrates to RLQ (McBurney's point) over 12–24 hours as peritoneum becomes inflamed
Anorexia (nearly universal) + nausea/vomiting + low-grade fever
Pain worsens with movement (peritoneal irritation) — patient lies still

Key Physical Exam Signs

McBurney's point: maximal tenderness 1/3 from ASIS to umbilicus
Rovsing's sign: RLQ pain with palpation of LLQ (peritoneal irritation)
Psoas sign: RLQ pain with right hip extension (retrocecal appendix)
Obturator sign: RLQ pain with internal rotation of right hip (pelvic appendix)
Dunphy's sign: RLQ pain worsened by coughing
Rebound tenderness: suggests peritonitis (perforation)

Alvarado Score (MANTRELS)

Migration of pain to RLQ — 1 pt
Anorexia — 1 pt
Nausea/vomiting — 1 pt
Tenderness in RLQ — 2 pts
Rebound tenderness — 1 pt
Elevated temperature — 1 pt
Leukocytosis — 2 pts
Score ≤4: low risk · 5–6: moderate → CT · ≥7: high risk → surgery

Imaging — CT vs Ultrasound vs MRI

CT Abdomen/Pelvis with Contrast

Best initial imaging in adults (sensitivity 94%, specificity 95%)
Findings: dilated appendix >6mm, periappendiceal fat stranding, appendicolith, abscess
Use in: adults with moderate risk or unclear diagnosis

Ultrasound — First-Line in Specific Populations

Children + pregnant women: US first (no radiation)
Non-compressible appendix >6mm + tenderness = appendicitis
Limitation: operator-dependent, often non-visualized appendix
If US non-diagnostic → MRI (pregnancy) or CT (non-pregnant)

Management

Treatment Pathway

Uncomplicated appendicitis: Laparoscopic appendectomy (gold standard). Antibiotics-first (non-operative) is an option in select patients — ~70% success at 1 year but ~30% require appendectomy eventually
Perforated appendicitis: IV antibiotics (ceftriaxone + metronidazole) → appendectomy. If periappendiceal abscess → CT-guided drainage first, interval appendectomy in 6–8 weeks
Pre-op antibiotics: Cefoxitin OR ceftriaxone + metronidazole (cover gram-negative rods + anaerobes)
WBC: elevated (often 11,000–18,000). CRP elevated. Markedly elevated WBC or high fever → concern for perforation

Board Traps

⚑ Appendicitis Board Traps

Atypical locations: retrocecal (most common variant — only psoas sign, no McBurney's), pelvic (obturator sign, can mimic PID)
In pregnancy: appendix displaced superiorly → pain may be in RUQ in 3rd trimester
Elderly: often atypical presentation, already perforated at diagnosis (minimal inflammatory response)
Pain relief before diagnosis: adequate analgesia does NOT interfere with exam findings or diagnosis — provide pain control
Normal WBC does NOT exclude appendicitis (especially early)

Hepatitis A & Hepatitis C

HAV: Fecal-Oral · Serology · Vaccine · HCV: DAAs · Sofosbuvir · Screening · Cirrhosis Risk · Reactivation

Hepatitis A (HAV)

Key Facts

Transmission: fecal-oral — contaminated food/water, travel to endemic areas, food handlers, daycare
Incubation: 2–6 weeks (average 28 days)
Self-limited — does NOT cause chronic hepatitis
Symptoms: acute jaundice, RUQ pain, fatigue, fever, dark urine, pale stools
Children often asymptomatic; adults more symptomatic
Fulminant hepatic failure: rare but possible in elderly, underlying liver disease

Serology

Anti-HAV IgM: Acute infection (appears early, lasts 3–6 months)
Anti-HAV IgG: Past infection OR vaccination (immunity)
No chronic carrier state — no HBsAg equivalent
Treatment: supportive only. No antivirals. Hospitalize for ALF or severe dehydration
Prevention: HAV vaccine (Havrix, Vaqta) × 2 doses. Post-exposure: vaccine + IG within 2 weeks

Hepatitis C (HCV)

HCV — The Chronic Liver Disease Epidemic

Transmission: blood-to-blood — IV drug use (most common), needle-stick, transfusions before 1992, tattoos
Sexual transmission: low risk (higher with HIV coinfection)
Vertical transmission: ~5% (lower than HBV)
75–85% of acute HCV becomes CHRONIC (unlike HAV = always resolves, HBV = 5–10% chronic)
Most patients asymptomatic for decades → cirrhosis → HCC
Leading cause of liver transplantation in the US

Screening

USPSTF: screen ALL adults age 18–79 years at least once
Screen more frequently: PWID, HIV+, prior incarceration, hemodialysis, born 1945–1965 (baby boomers)
HCV antibody test (anti-HCV): initial screen
If anti-HCV +: confirm with HCV RNA (PCR)
HCV RNA +: active infection → genotype to guide treatment

Treatment — Direct-Acting Antivirals (DAAs)

Goal: sustained virologic response (SVR) = undetectable HCV RNA 12 weeks after treatment = cure
Ledipasvir/sofosbuvir (Harvoni): Genotype 1 (most common in US), 8–12 weeks
Glecaprevir/pibrentasvir (Mavyret): Pan-genotypic, 8 weeks most patients
Sofosbuvir/velpatasvir (Epclusa): Pan-genotypic
SVR cure rates: >95% — this is a curable disease
⚑ Board trap: SVR (cure) does NOT eliminate cirrhosis risk that was already present → continue HCC surveillance

Rapid Review — Viral Hepatitis Comparison

HAV: fecal-oral, acute only, vaccine-preventable. Anti-HAV IgM = acute. Anti-HAV IgG = immune
HBV: blood/sexual/vertical, 5–10% chronic, vaccine-preventable. Window period = only anti-HBc IgM positive
HCV: blood-to-blood, 75–85% chronic, NO vaccine. Screen all adults 18–79 once. Curable with DAAs
HDV: defective virus — requires HBV surface antigen to replicate. Only in HBV-infected patients
HEV: fecal-oral like HAV; dangerous in pregnancy (mortality 20–25% in 3rd trimester)

NAFLD & NASH — Non-Alcoholic Fatty Liver Disease

FIB-4 Score · FibroScan · MAFLD Rebranding · GLP-1 Agonists · Resmetirom · Biopsy Indications · Cirrhosis Progression

Definition & Spectrum

NAFLD Spectrum

NAFLD (steatosis only): hepatic fat >5% without significant inflammation — benign course in most
NASH (steatohepatitis): steatosis + inflammation + hepatocyte injury (ballooning) ± fibrosis — progressive
NASH cirrhosis: end-stage — HCC risk even without cirrhosis (distinct from other liver diseases)
New preferred term: MAFLD (metabolic-associated fatty liver disease) — 2023 nomenclature update
Most common liver disease in the world; affects ~25% of global population

Risk Factors & Associations

Metabolic Syndrome Connection

Type 2 diabetes (NAFLD in 70–80% of T2DM)
Obesity (especially central/visceral)
Dyslipidemia (↑TG, ↓HDL)
Hypertension · Insulin resistance
Hypothyroidism · PCOS · Sleep apnea also associated
LFTs: ALT > AST (opposite of alcoholic) — but often normal even with significant fibrosis

Non-Invasive Fibrosis Assessment

FIB-4 Score (First-Line)

Formula: (Age × AST) ÷ (Platelets × √ALT)
<1.30: low risk of advanced fibrosis → monitor
1.30–2.67: indeterminate → FibroScan or ELF test
>2.67: high risk of advanced fibrosis → GI/Hepatology referral

FibroScan (Transient Elastography)

Non-invasive liver stiffness measurement
Results in kPa — higher = more fibrosis
Can also measure CAP score (hepatic steatosis)
Limitations: obesity, ascites may affect accuracy

Liver Biopsy — When to Use

Indeterminate non-invasive testing when management decision hinges on fibrosis stage
Competing diagnoses (autoimmune hepatitis, other)
Pathology: steatosis + lobular inflammation + hepatocyte ballooning ± Mallory-Denk bodies ± fibrosis
NASH Activity Score (NAS ≥5): favors NASH diagnosis

Treatment

Lifestyle — Foundation of Treatment

Weight loss ≥7–10%: improves steatosis, inflammation, and fibrosis
Mediterranean diet preferred
Exercise: improves insulin sensitivity independently of weight loss
Alcohol abstinence (even though non-alcoholic, alcohol accelerates progression)

Pharmacotherapy (Evolving)

Semaglutide (GLP-1 agonist): FDA approved for NASH with fibrosis (resolutions NASH in ~60% at high dose) — 2024
Resmetirom: Thyroid hormone receptor β agonist — FDA approved March 2024 for NASH with fibrosis stage F2–F3. First disease-specific drug approved
Vitamin E: improves histology in non-diabetic NASH adults — not for diabetics or cirrhosis
Pioglitazone: improves NASH histology in diabetics — weight gain and fluid retention concerns
Statins: safe in NAFLD/NASH — do not worsen liver disease, may have anti-inflammatory benefit

Hernias

Inguinal (Direct vs Indirect) · Femoral · Hiatal · Umbilical · Incarceration vs Strangulation · Richter's

Inguinal Hernias — Most Common Type

Indirect Inguinal (Most Common Overall)

Passes through internal inguinal ring → inguinal canal → external ring ± into scrotum
Along the path of the spermatic cord (through internal ring)
Both sexes but predominantly male. All ages, especially children
Congenital: patent processus vaginalis
Lateral to inferior epigastric vessels

Direct Inguinal (Acquired)

Protrudes through Hesselbach's triangle (medial to inferior epigastric vessels)
Weakness of posterior inguinal wall (transversalis fascia)
Older men, associated with chronic straining, obesity, heavy lifting
Rarely strangulates (wide neck)
Memory: "Direct" = pushes straight through (medial); "Indirect" = indirect path through ring (lateral)

Femoral Hernia

Below inguinal ligament, through femoral canal (medial to femoral vessels)
More common in women (narrow pelvis creates smaller femoral canal, paradoxically higher strangulation risk)
High strangulation risk (narrow femoral ring)
Present as tender groin mass below and lateral to pubic tubercle

Complications — Must-Know Distinctions

Reducible

Contents return to abdomen with manual pressure or recumbency
No emergency — elective repair

Incarcerated

Contents trapped — cannot reduce
Tender, firm lump
Obstruction may occur
Urgent surgical repair

Strangulated ⭐ EMERGENCY

Blood supply compromised → ischemia → necrosis
Severe pain, systemic signs (fever, leukocytosis, peritonitis)
Emergent surgery — high mortality if delayed

Richter's Hernia

Only antimesenteric wall of bowel in the hernia sac (not full circumference)
Can strangulate without causing complete obstruction — delayed diagnosis common

Other Hernia Types

Hiatal Hernia

Type I (sliding, 95%): GEJ slides above diaphragm — associated with GERD
Type II (paraesophageal): fundus herniates, GEJ remains below — strangulation risk
Symptoms: GERD, dysphagia, early satiety
Diagnosis: barium swallow or EGD
Large paraesophageal: surgical repair due to strangulation risk

Other Types

Umbilical: common in neonates (most close by age 5), obese adults, ascites
Incisional/Ventral: at prior surgical scar site
Spigelian: lateral edge of rectus muscle (spontaneous); rare
Obturator: rare; elderly women; Howship-Romberg sign (medial thigh pain)

Small & Large Bowel Obstruction

Air-Fluid Levels · Adhesions · Closed-Loop · Volvulus · NGT Decompression · Surgical Indications

Small Bowel Obstruction (SBO) — Most Common

SBO — Causes & Presentation

Most common cause: adhesions from prior surgery (60–70%). Others: hernia (15%), malignancy, Crohn stricture, volvulus, intussusception
Presentation: crampy periumbilical pain + nausea/vomiting (bilious early; feculent late) + abdominal distension + inability to pass flatus/stool
High-pitched "tinkling" bowel sounds early → absent (silent) late (ileus or strangulation)
Vomiting prominent in proximal SBO; distension prominent in distal SBO

Imaging

AXR (supine + upright): dilated small bowel loops >3cm, air-fluid levels, paucity of colon gas
CT abdomen with IV contrast: best — identifies level, cause, and complications (ischemia)
"String of pearls" sign: air bubbles in fluid-filled loops on CT
Transition point: where dilated bowel meets decompressed bowel = level of obstruction

Management

Partial (incomplete) SBO: NPO + IV fluids + NGT decompression → 75% resolve non-operatively
Complete SBO: surgical exploration when no improvement in 24–48h
Strangulation signs: fever, peritoneal signs, leukocytosis, acidosis, CT showing ischemia → emergent surgery
Gastrografin challenge: water-soluble contrast trial — therapeutic + diagnostic in partial SBO

Large Bowel Obstruction (LBO)

LBO — Key Differences from SBO

Most common cause: colorectal cancer (60%). Others: diverticular stricture, volvulus
Gradual onset: constipation → obstipation (no stool OR gas)
Distension prominent; vomiting late (feculent)
AXR: dilated colon proximal to obstruction, "picture frame" appearance
Risk of cecal perforation: cecal diameter >12 cm → emergent decompression

Sigmoid Volvulus

Sigmoid colon twists on its mesentery — common in elderly, nursing home, chronic constipation
AXR: "coffee bean" sign (inverted U of distended sigmoid)
Treatment: sigmoidoscopy decompression (first-line if viable bowel) → elective sigmoid resection

Cecal Volvulus

Cecum twists — younger patients with hypermobile cecum
AXR: "kidney bean" sign in LUQ or mid-abdomen
Surgical emergency — no safe endoscopic decompression

Board Traps

⚑ Obstruction Board Traps

Paralytic ileus vs SBO: Ileus = absent bowel sounds, dilated bowel WITHOUT obstruction (post-op, electrolyte disorder, opioids, peritonitis). SBO = high-pitched sounds early
Closed-loop obstruction: Both ends of bowel segment obstructed → rapid distension → ischemia/perforation. Surgical emergency
Ogilvie syndrome (pseudo-obstruction): Colonic dilation without mechanical obstruction — ICU patients, post-op. Treat with neostigmine (IV) if cecum >12cm. Colonoscopic decompression second-line

Hemorrhoids & Anal Fissure

Internal vs External · Grading · Thrombosed Hemorrhoid · Fissure Location · Topical Nitrate · Botox · Lateral Internal Sphincterotomy

Hemorrhoids

Internal Hemorrhoids

Above dentate line — visceral innervation (NOT painful)
Presentation: painless bright red blood on toilet paper or in bowl (not mixed with stool)
Grading: I=no prolapse; II=prolapse reduces spontaneously; III=needs manual reduction; IV=irreducible
Treatment: Grade I–II: fiber, sitz baths, topical agents. Grade III: rubber band ligation. Grade IV: hemorrhoidectomy

External Hemorrhoids

Below dentate line — somatic innervation (PAINFUL)
Thrombosed external hemorrhoid: acute, intensely painful firm perianal lump
Treatment of thrombosed: excision within 72h of onset (not just incision). After 72h: sitz baths + analgesics (pain peaks and then resolves)
⚑ Do NOT treat thrombosed hemorrhoid with anticoagulation

Anal Fissure

Anal Fissure — Recognition & Treatment

Linear tear in anoderm — intensely painful during and after defecation
Bright red rectal bleeding with pain (opposite of internal hemorrhoids — painless)
Location: posterior midline (90%). Anterior midline (10%, more common in women)
Lateral or multiple fissures: consider Crohn disease, syphilis, TB, HIV, anal cancer
Mechanism: internal anal sphincter hypertonia → ischemia of posterior commissure

Acute Fissure (<6 weeks)

Dietary fiber + stool softeners + sitz baths
Topical nitroglycerin 0.4% (first-line pharmacologic) — headache is common side effect
Topical diltiazem or nifedipine: CCB alternative, fewer side effects

Chronic Fissure (>6 weeks) / Refractory

Botulinum toxin injection: relaxes internal sphincter → improves blood flow
Lateral internal sphincterotomy (LIS): surgical gold standard. Divides part of internal sphincter → ↓ hypertonia. Risk: incontinence

Module D · Must-Know Differentials

High-Yield Differentials & Distinguishing Features

The following differentials represent the highest-frequency diagnostic challenges in GI and hepatology on the PANCE/PANRE. Each framework identifies the single pivotal feature that separates one diagnosis from another — the exact clinical reasoning skill the exam rewards.

Tier 1

Differential D-1

Acute Abdominal Pain — Location-Based Framework

RUQ · LUQ · RLQ · LLQ · Periumbilical · Diffuse · Epigastric

★★★ Most-Tested GI DifferentialMultiple Surgical Emergency Traps

Location-Based Differential — The Primary Framework

Location	Top Diagnoses	Key Distinguishing Feature	Cannot Miss
RUQ	Cholecystitis (#1), cholangitis, hepatitis, Fitz-Hugh–Curtis, hepatic abscess, PUD	Murphy's sign + fever + fat/female/forty = cholecystitis. Charcot's triad (RUQ + fever + jaundice) = cholangitis. Jaundice alone = hepatitis or CBD stone.	Cholangitis: do NOT delay ERCP for additional imaging. Biliary sepsis is life-threatening.
Epigastric	GERD, PUD, gastritis, pancreatitis, NSTEMI (referred), Zollinger-Ellison	Radiates to back + nausea/vomiting + lipase ≥3× = pancreatitis. Burning + worse with meals/lying + relieved by antacids = GERD/PUD. Epigastric pain + ECG changes = rule out ACS.	Epigastric pain + diaphoresis + radiation to jaw/arm = NSTEMI — always get an EKG.
RLQ	Appendicitis (#1), ovarian pathology (cyst, torsion, ectopic), IBD (terminal ileitis), cecal diverticulitis, mesenteric adenitis	McBurney's point tenderness + Rovsing's + rebound = appendicitis. Young female + sudden onset + adnexal tenderness = ovarian torsion (emergent). Positive β-hCG + RLQ = ectopic until proven otherwise.	Ovarian torsion and ectopic pregnancy are both surgical emergencies — do NOT delay with serial imaging.
LLQ	Diverticulitis (#1), IBD (UC/Crohn), ovarian pathology (left), constipation, ischemic colitis	LLQ + fever + leukocytosis + CT fat stranding = diverticulitis. Bloody diarrhea + mucus + continuous from rectum = UC. Colicky + hematochezia + elderly + post-hypotension event = ischemic colitis (watershed area).	Ischemic colitis: history of hypotension, aortic surgery, or low-flow state is the pivotal clue.
Periumbilical → RLQ migration	Appendicitis (classic migration pattern)	Periumbilical pain migrating to RLQ over 24–48h + anorexia + low-grade fever = appendicitis until proven otherwise.	Perforation risk increases sharply after 72 hours — do not delay diagnosis.
Diffuse / Generalized	Peritonitis (perforated viscus), mesenteric ischemia, bowel obstruction, SBP in cirrhotic, DKA	Rigid "board-like" abdomen + guarding + rebound = peritonitis — surgical emergency. Pain out of proportion to exam = mesenteric ischemia. Distension + obstipation + air-fluid levels = SBO.	Mesenteric ischemia: pain out of proportion to physical exam is the classic board clue. CT angiography + emergent vascular surgery.

⚑ Board Traps — Abdominal Pain Differential

Always get an EKG in epigastric pain — inferior MI commonly presents as epigastric pain, especially in diabetics and women. Missing an NSTEMI while treating "GI pain" is a high-stakes board scenario.
Pain out of proportion to physical exam = mesenteric ischemia — the abdomen looks deceptively benign early. In any patient with risk factors (AF, hypercoagulable, atherosclerosis), this presentation demands CT angiography immediately.
RLQ pain in a woman of reproductive age: always check β-hCG first — ectopic pregnancy before appendicitis. The test takes 2 minutes and prevents a fatal misdiagnosis.
Charcot's triad is cholangitis, Reynolds' pentad is suppurative cholangitis — adding AMS and hypotension to Charcot's triad = life-threatening emergency requiring emergent biliary drainage, not just antibiotics.

Tier 1

Differential D-2

Jaundice — Pre-hepatic vs Hepatic vs Post-hepatic

Bilirubin Type · Conjugated vs Unconjugated · LFT Patterns · Imaging Decision

★★★ PANCE Priority

The Three-Category Framework

Category	Bilirubin Type	Mechanism	Classic Causes	Key LFT Pattern
Pre-hepatic (Hemolytic)	Unconjugated (indirect) ↑	Excess RBC destruction → overwhelms hepatic conjugation	Hemolytic anemia (sickle cell, G6PD, hereditary spherocytosis), transfusion reaction, resorbing hematoma	LFTs normal. ↑ LDH, ↑ reticulocytes, ↓ haptoglobin. Normal urine (no bilirubinuria — unconjugated is albumin-bound).
Hepatic (Hepatocellular)	Both ↑ (mixed)	Hepatocyte injury → impaired conjugation AND impaired secretion	Viral hepatitis, alcoholic hepatitis, NASH/NAFLD, drug-induced (acetaminophen, isoniazid), autoimmune hepatitis, Wilson's disease	AST/ALT markedly elevated (>500 in viral/toxic hepatitis). ALP mildly elevated. Bilirubin both fractions elevated.
Post-hepatic (Obstructive/Cholestatic)	Conjugated (direct) ↑	Bile flow obstruction → conjugated bilirubin regurgitates into blood	Choledocholithiasis, pancreatic cancer (painless jaundice), cholangiocarcinoma, PSC, PBC, biliary stricture	ALP/GGT markedly elevated. AST/ALT mildly elevated. Dark urine (bilirubinuria). Pale stools (no bilirubin reaching gut).

The Pivotal Clinical Clues

Painless jaundice in an elderly patient = pancreatic cancer until proven otherwise. Courvoisier sign (palpable, non-tender gallbladder) in a jaundiced patient = malignant obstruction. Get CT abdomen + CA 19-9.
Jaundice + RUQ pain + fever = Charcot's triad = cholangitis. Not hepatitis — the fever and pain combination points to biliary obstruction with infection.
Jaundice + AST:ALT ratio >2:1 + GGT elevated = alcoholic hepatitis. The ratio alone doesn't diagnose ALD — must have clinical context, but ratio >2:1 is a strong pointer.
Jaundice + pruritus + middle-aged woman + AMA positive = primary biliary cholangitis (PBC). Autoimmune destruction of intrahepatic bile ducts. ALP and GGT markedly elevated.
Jaundice + young patient + neuropsychiatric symptoms + Kayser-Fleischer rings = Wilson's disease. Low ceruloplasmin. Treat with penicillamine or trientine.

Neonatal Jaundice — Special Board Scenario

Physiologic jaundice: Appears day 2–3, peaks day 4–5, resolves by day 10–14. Unconjugated. Benign — phototherapy if bilirubin approaching exchange threshold.
Pathologic jaundice: Appears in first 24 hours, or conjugated at any time, or bilirubin rising >5 mg/dL/day → workup required.
Breastfeeding jaundice vs breast milk jaundice: Breastfeeding = inadequate intake + dehydration (days 2–5). Breast milk = substance in milk inhibits conjugation (days 5–14, can persist weeks). Continue breastfeeding in both.

⚑ Board Traps — Jaundice

Painless jaundice = cancer until proven otherwise. Never anchor on a benign cause in an elderly patient with painless progressive jaundice, weight loss, and a palpable gallbladder.
Conjugated hyperbilirubinemia in a neonate is ALWAYS pathologic — biliary atresia, choledochal cyst, neonatal hepatitis. Needs urgent workup. Unconjugated is usually physiologic.
Gilbert's syndrome: Benign unconjugated hyperbilirubinemia triggered by fasting, illness, or stress. All other LFTs normal. No treatment needed. Common board distractor.
Dubin-Johnson vs Rotor syndrome: Both cause isolated conjugated hyperbilirubinemia with otherwise normal LFTs. Rare but boards love them. Dubin-Johnson: dark liver on gross exam, abnormal coproporphyrin ratio. Rotor: no liver pigmentation.

Tier 1

Differential D-3

GI Bleeding — Upper vs Lower vs Obscure

BUN:Cr Ratio · Hematemesis vs Melena vs Hematochezia · Presentation-to-Source Mapping

★★★ PANCE PriorityTransfusion Threshold Trap

Bleeding Presentation → Source Mapping

Presentation	Source Location	Top Causes	Key Diagnostic Step
Hematemesis (bright red or coffee-ground)	Upper GI (proximal to ligament of Treitz)	PUD (#1), esophageal varices, Mallory-Weiss tear, esophagitis, Dieulafoy lesion	Urgent EGD within 24h (within 12h for suspected varices)
Melena (black, tarry, malodorous stool)	Usually Upper GI; occasionally proximal small bowel or right colon	Same as hematemesis causes; also right colonic bleeding with slow transit	BUN:Cr ratio >20:1 suggests upper GI source. EGD first.
Hematochezia (bright red per rectum)	Usually Lower GI; massive UGIB can also cause	Diverticular bleed (#1 in elderly), angiodysplasia, hemorrhoids (#1 overall), IBD, colorectal cancer, ischemic colitis	Colonoscopy after stabilization. CT angiography if massive/unstable.
Occult bleeding (positive FOBT, iron deficiency)	Any location — slow, chronic	CRC (most feared), polyps, celiac disease, angiodysplasia, PUD	Colonoscopy first (most common source in adults ≥45). EGD if colonoscopy negative.

The BUN:Cr Ratio — The Upper vs Lower GI Clue

BUN:Cr ratio >20:1 in a bleeding patient = upper GI source. Blood is protein; digestion in the small bowel generates urea → elevated BUN without proportional creatinine rise.
BUN:Cr ratio normal = lower GI source more likely (blood has not traversed the small bowel for protein digestion).
Limitation: Ratio also elevated in pre-renal azotemia — use in context of clinical presentation.

Transfusion Thresholds — The Most Tested GI Numbers

⚑ Transfusion Rules — Non-Negotiable Board Facts

Hgb threshold for transfusion: <7 g/dL for all GI bleeding (TRICC + TRIGGER trials). Target Hgb 7–9 after transfusion.
Exception: Hgb <8–9 if active cardiovascular disease (ACS, severe angina) — myocardium cannot tolerate lower threshold.
Variceal bleeding: restrictive transfusion is CRITICAL. Over-transfusing raises portal pressure → re-bleeding and death. Target Hgb ~7, NOT 10.
INR does NOT predict bleeding risk in cirrhosis — cirrhotic liver makes both pro- and anti-coagulants. Do NOT transfuse FFP based on INR alone in cirrhosis.

⚑ Board Traps — GI Bleeding

Massive UGIB can present as hematochezia — when bleeding is so rapid that blood moves through the colon before becoming melanotic. Clinical context (hemodynamic instability + hematochezia) = consider UGIB first.
Diverticular bleeding is painless — LLQ pain + rectal bleeding = diverticulitis, NOT diverticular bleed. Diverticular bleed is large-volume, painless, and usually stops spontaneously (80%).
Epinephrine injection alone is never sufficient endoscopic treatment — always add a second modality (clips, thermal coagulation). Epi alone = 30% re-bleeding rate.
Tranexamic acid has NO role in GI bleeding (HALT-IT trial: no mortality benefit, possible harm from thromboembolic events). Do not use it.

Tier 1

Differential D-4

Chronic Diarrhea — Inflammatory vs Osmotic vs Secretory vs Malabsorptive

IBD vs IBS vs Celiac vs Microscopic Colitis vs Infectious · Fasting Test · Fecal Calprotectin

★★★ PANCE Priority

The Four-Category Framework

Type	Key Feature	Fasting Effect	Classic Causes
Inflammatory	Bloody diarrhea, fever, elevated fecal calprotectin, WBC in stool	Does NOT stop with fasting	IBD (UC/Crohn), infectious colitis (Salmonella, Shigella, C. diff), ischemic colitis, radiation colitis
Secretory	Large-volume, watery, non-bloody. Osmotic gap normal (<50 mOsm/kg). Persists with fasting.	Does NOT stop with fasting — hallmark	VIPoma (pancreatic cholera), carcinoid, microscopic colitis, bile acid malabsorption, Addison's disease
Osmotic	Diarrhea stops with fasting. Osmotic gap elevated (>125 mOsm/kg). Watery.	STOPS with fasting — hallmark	Lactose intolerance, sorbitol, magnesium antacids, lactulose, celiac disease (mixed osmotic + malabsorptive)
Malabsorptive	Steatorrhea (greasy, foul-smelling, floats), weight loss, fat-soluble vitamin deficiencies	Partially improves	Celiac disease, chronic pancreatitis (exocrine insufficiency), short bowel syndrome, Whipple's disease, Giardia

IBD vs IBS vs Celiac — The Most Tested Triad

Feature	IBD (UC/Crohn)	IBS	Celiac Disease
Blood in stool	Yes (especially UC)	No — alarm feature if present	Rarely (if severe)
Nocturnal symptoms	Yes — wakes from sleep	No — rules out IBS	Possible
Weight loss	Yes (Crohn more than UC)	No — alarm feature if present	Yes (malabsorption)
Fecal calprotectin	Elevated	Normal	May be mildly elevated
Key serologic test	CRP, ESR, ANCA/ASCA	None (clinical diagnosis)	Anti-tTG IgA (must be on gluten diet)
Diagnostic gold standard	Colonoscopy with biopsy	Rome IV criteria (clinical)	Duodenal biopsy (villous atrophy)

⚑ Board Traps — Diarrhea Differential

Nocturnal diarrhea rules out IBS — if a patient's diarrhea wakes them from sleep, it is organic disease. This single feature eliminates IBS from the differential and mandates workup.
Test celiac BEFORE starting a gluten-free diet — anti-tTG IgA normalizes within weeks of GFD, making diagnosis impossible. Always test while on a gluten-containing diet.
Secretory diarrhea persists with fasting; osmotic diarrhea stops — this is the single most important physiologic distinction for the boards.
Microscopic colitis: Normal-appearing colonoscopy + watery secretory diarrhea in a middle-aged woman on NSAIDs, PPIs, or SSRIs. Diagnosis requires mucosal biopsy despite normal gross appearance.
C. diff: do NOT give anti-motility agents (loperamide) — slows clearance of toxin, can precipitate toxic megacolon.

Tier 1

Differential D-5

Elevated LFTs — Hepatocellular vs Cholestatic Pattern

AST/ALT vs ALP/GGT · The AST:ALT Ratio · Alcohol vs Viral vs Autoimmune vs Drug-Induced

★★★ PANCE Priority

LFT Pattern Recognition Framework

Pattern	Dominant Elevation	Mechanism	Top Causes
Hepatocellular	AST and ALT markedly elevated (often >500–1000)	Hepatocyte necrosis/injury	Viral hepatitis (A, B, C), acetaminophen toxicity, ischemic hepatitis ("shock liver"), autoimmune hepatitis, Wilson's disease
Alcoholic hepatitis	AST:ALT ratio >2:1 (rarely exceeds 8:1). AST usually <300.	Mitochondrial injury → disproportionate AST release	Alcoholic liver disease — the ratio is the key, not the absolute value
Cholestatic/Obstructive	ALP and GGT markedly elevated. Bilirubin (conjugated) elevated. AST/ALT mildly elevated.	Bile flow obstruction	Choledocholithiasis, pancreatic cancer, cholangiocarcinoma, PSC, PBC, drug-induced cholestasis
Infiltrative	ALP elevated out of proportion to bilirubin. AST/ALT mildly elevated. GGT elevated.	Space-occupying lesions or granulomas replacing liver parenchyma	Sarcoidosis, metastatic cancer, lymphoma, hepatic abscess, amyloidosis
Isolated hyperbilirubinemia	Bilirubin elevated; all other LFTs normal	Isolated bilirubin processing defect	Gilbert's syndrome (unconjugated, benign), Dubin-Johnson/Rotor (conjugated, benign), hemolysis

AST:ALT Ratio — The Most Board-Tested Liver Calculation

AST:ALT >2:1 = alcoholic liver disease until proven otherwise. The ratio reflects mitochondrial AST release from alcohol-damaged hepatocytes.
AST:ALT >8:1 in alcoholic hepatitis — rarely exceeds this. If ratio is extraordinarily high (>50:1), consider ischemic hepatitis ("shock liver") or acetaminophen toxicity.
Viral hepatitis: AST:ALT ratio usually ≤1 (ALT > AST) — hepatocyte cytoplasm preferentially releases ALT.
ALP elevated + GGT elevated = confirmed hepatic origin (GGT not elevated in bone disease). ALP elevated + GGT normal = bone disease (Paget's, bone metastases).
Ischemic hepatitis ("shock liver"): AST/ALT can exceed 1000–5000 IU/L rapidly (within 24–48h of hypoperfusion event). History of hypotension, cardiac arrest, or sepsis is the clue.

⚑ Board Traps — LFT Interpretation

ALP elevation: confirm hepatic origin with GGT — ALP is also elevated in bone disease (Paget's, fractures, bone metastases). GGT co-elevation confirms hepatic/biliary source.
AST:ALT >2:1 does NOT diagnose alcoholism alone — it is a strong clue requiring clinical context. Wilson's disease and ischemic hepatitis can also produce elevated ratios.
Normal LFTs do NOT rule out significant liver disease — compensated cirrhosis often has near-normal LFTs. Assess synthetic function (albumin, INR, bilirubin) and platelet count.
Acetaminophen toxicity: AST/ALT can exceed 10,000 IU/L — the highest values seen in clinical medicine. The hepatocellular pattern with massive transaminase elevation + history of acetaminophen ingestion + PT prolongation = acute liver failure. Give NAC immediately.

Tier 2

Differential D-6

Dysphagia — Oropharyngeal vs Esophageal · Solids vs Liquids

Achalasia · Stricture · Esophageal Cancer · Neuromuscular · Schatzki Ring

★★ High Yield

The Two-Step Dysphagia Framework

Step 1 — Oropharyngeal vs Esophageal: Oropharyngeal = difficulty initiating swallow, coughing/choking/nasopharyngeal regurgitation with first bite. Causes: stroke, Parkinson's, ALS, myasthenia gravis. Esophageal = food gets stuck several seconds after swallow. Causes: mechanical or motility.
Step 2 (Esophageal) — Solids only vs Solids AND liquids:
- Solids only → mechanical obstruction (stricture, ring, cancer). Progressive worsening = cancer. Intermittent = Schatzki ring.
- Solids AND liquids → motility disorder (achalasia, diffuse esophageal spasm, scleroderma). Regurgitation of undigested food = achalasia.

Key Diagnoses by Distinguishing Feature

Diagnosis	Pattern	Key Distinguishing Feature	Diagnostic Test
Achalasia	Solids AND liquids, regurgitation of undigested food, worse with cold liquids	"Bird-beak" tapering on barium swallow. Manometry: absent peristalsis + elevated LES pressure. Regurgitation of undigested food (not acid) is the clue.	Manometry (gold standard), barium swallow, EGD to exclude malignancy
Esophageal stricture (peptic)	Progressive solids-only dysphagia. History of GERD.	Gradual worsening over months to years. History of chronic GERD. Dilated esophagus proximal to stricture on barium.	Barium swallow → EGD with dilation
Schatzki ring	Intermittent solids-only dysphagia (especially with large pieces of meat — "steakhouse syndrome")	Episodic, not progressive. Specific to solid boluses. Asymptomatic between episodes.	Barium swallow (thin ring at GEJ). EGD + dilation.
Esophageal cancer	Progressive solids then liquids dysphagia. Weight loss.	Progressive dysphagia + weight loss in a smoker/drinker (SCC) or GERD patient (adenocarcinoma) = cancer until proven otherwise. Alarm feature — immediate EGD.	EGD with biopsy. CT staging.
Diffuse esophageal spasm	Intermittent chest pain + dysphagia to both solids and liquids	"Corkscrew esophagus" on barium. Severe chest pain mimicking cardiac disease. Relieved by nitrates.	Manometry (simultaneous contractions), barium swallow

⚑ Board Traps — Dysphagia

Progressive dysphagia to solids → then liquids + weight loss = esophageal cancer — this progression pattern is the classic board presentation. EGD immediately.
Achalasia regurgitation = undigested food (not acid/bile) — because food sits in the esophagus, not the stomach. This distinguishes it from GERD regurgitation.
Diffuse esophageal spasm relieved by nitrates — same as angina. This is a classic board trap: chest pain + dysphagia + relieved by nitroglycerin. Always rule out cardiac cause first.
Pseudoachalasia: New-onset dysphagia in an elderly patient that looks like achalasia = malignancy at or near the GEJ compressing the myenteric plexus. Always do EGD to exclude before treating as achalasia.

Tier 1

Differential D-7

Acute vs Chronic Pancreatitis vs Pancreatic Cancer

Atlanta Criteria · Severity Scoring · Gallstone vs Alcohol · Pseudocyst vs Abscess · Cancer Red Flags

★★★ PANCE PriorityAntibiotic & Feeding Traps

Three-Disease Comparison Framework

Feature	Acute Pancreatitis	Chronic Pancreatitis	Pancreatic Cancer
Pain character	Severe, acute onset, epigastric → back, constant, nausea/vomiting	Chronic, recurring epigastric + back pain. Worse after eating. Improved sitting forward.	Painless jaundice (#1 presentation). Or dull, gnawing back pain in advanced disease.
Key lab finding	Lipase ≥3× ULN (more specific than amylase). Amylase rises first, lipase stays elevated longer.	Lipase may be normal (burned-out gland). Steatorrhea. Fat-soluble vitamin deficiency.	CA 19-9 elevated (not diagnostic alone). Bilirubin elevated (obstructive pattern).
Imaging	CT shows pancreatic edema/inflammation. CECT for severity/necrosis (not required for diagnosis).	CT/X-ray: pancreatic calcifications (pathognomonic). Ductal dilation. Atrophy.	CT: hypoenhancing pancreatic mass. Double duct sign (CBD + pancreatic duct dilation).
Most common cause	Gallstones (#1), alcohol (#2). GET SMASHED mnemonic.	Alcohol (#1 in US). Hereditary/genetic (CFTR, PRSS1, SPINK1) in younger patients.	Smoking (#1 modifiable). Chronic pancreatitis. DM (new-onset in elderly may be early sign).
Classic board clue	Sudden epigastric pain + N/V + lipase ≥3× ULN = diagnosis (2 of 3 Atlanta criteria).	Triad: abdominal pain + steatorrhea + diabetes = chronic pancreatitis until proven otherwise.	Painless jaundice + palpable gallbladder (Courvoisier sign) + weight loss = pancreatic head cancer.

Acute Pancreatitis Management — Key Decision Points

Aggressive IV fluid resuscitation: Lactated Ringer's preferred over normal saline (reduces SIRS/organ failure). 250–500 mL/hr initially, reassess every 6 hours.
Early enteral nutrition (within 24–48h if tolerated): Oral/nasogastric feeding is safe and superior to parenteral nutrition. NPO is outdated — feed early.
Prophylactic antibiotics for sterile necrosis: NOT indicated — multiple RCTs show no benefit. Reserve antibiotics for infected necrosis (gas in necrosis on CT + fever + clinical decline).
ERCP in biliary pancreatitis: Indicated within 24h if cholangitis or persistent biliary obstruction. NOT needed for uncomplicated biliary pancreatitis without obstruction.
Cholecystectomy during same hospitalization for mild biliary pancreatitis after resolution — reduces 30-day recurrence rate from ~18% to <3%.

⚑ Board Traps — Pancreatitis

Lipase is preferred over amylase — amylase is less specific (elevated in parotitis, bowel perforation, ectopic pregnancy). Lipase stays elevated longer and is more specific for pancreatic injury.
Prophylactic antibiotics in sterile pancreatitis = NOT indicated — a persistent board trap. Multiple RCTs show no mortality benefit. Antibiotics only for confirmed infected necrosis.
Early enteral nutrition is safe and beneficial — do NOT leave a patient with pancreatitis NPO for days. Feed early (oral or NG if needed) to maintain gut barrier and reduce infectious complications.
Courvoisier sign = painless jaundice + palpable non-tender gallbladder = malignant biliary obstruction (pancreatic cancer, cholangiocarcinoma). NOT cholelithiasis (chronically inflamed GB cannot dilate).
Pancreatic pseudocyst vs walled-off necrosis: Pseudocyst = fluid collection after 4 weeks, thin wall, no solid debris. Walled-off necrosis = solid + fluid, thicker wall. Drainage only if symptomatic (infected, compressing, not spontaneously resolving).

Module E · Comprehensive Board Pearls

Board Pearls — Organized by Domain

These pearls represent the exact clinical decision points most frequently tested on PANCE/PANRE GI questions — the specific facts that separate passing from failing candidates.

Tier 1

Board Pearls — Upper GI

GERD · PUD · H. pylori · GI Bleeding · Varices

★★★ Highest Yield

PPIs must be taken 30–60 minutes BEFORE meals — not at bedtime, not with food. Bedtime dosing reduces efficacy by ~50%. This is the single most tested GERD pharmacology fact.
Gastric ulcers must always be biopsied at endoscopy — duodenal ulcers are almost never malignant. Gastric ulcers can harbor adenocarcinoma.
Stop PPIs ≥2 weeks before H. pylori testing (UBT or stool antigen) to avoid false-negative results. Wait ≥4 weeks after completing antibiotic therapy before confirming eradication.
H. pylori serology (IgG) cannot be used to confirm active infection or eradication — antibodies persist years after treatment. Use UBT or stool antigen for active infection and eradication testing.
NSAID-induced PUD: add a PPI for gastroprotection — misoprostol is an alternative but poorly tolerated. Stop the NSAID if possible. H. pylori should always be tested and treated in NSAID users with PUD.
Variceal bleeding: restrictive transfusion strategy (target Hgb ~7) — over-transfusion raises portal pressure and increases re-bleeding mortality. This is the most tested variceal management fact.
Octreotide + ceftriaxone + endoscopy within 12h = the three pillars of variceal bleeding management. Erythromycin IV before endoscopy improves visualization by emptying the stomach.
INR does not predict bleeding risk in cirrhosis — do not transfuse FFP based on INR alone. The liver makes both pro- and anti-coagulants; the INR reflects coagulation factor deficiency only.
Tranexamic acid has no role in GI bleeding — HALT-IT trial showed no mortality benefit and possible harm from thromboembolic events.
Non-variceal UGIB: epinephrine injection alone is insufficient — always add a second hemostatic modality (clips, thermal coagulation). Dual therapy reduces re-bleeding by 50%.

Tier 1

Board Pearls — Hepatology

Viral Hepatitis · Cirrhosis · SBP · HRS · Acute Liver Failure · Metabolic Liver Disease

★★★ Highest Yield

AST:ALT >2:1 + GGT elevated = alcoholic liver disease — the ratio reflects mitochondrial injury from alcohol. AST rarely exceeds 300 in alcoholic hepatitis (if >300, consider another diagnosis).
Hepatitis B window period: HBsAg has cleared, Anti-HBs not yet detectable. Only Anti-HBc IgM is positive. This is the most tested HBV serology scenario. Patient is still infectious.
Anti-HBs alone positive = immune from vaccination (never infected). Anti-HBc + Anti-HBs = immune from prior infection. HBsAg positive = currently infected.
Hepatitis C: test with HCV antibody; confirm with HCV RNA. Anti-HCV alone cannot distinguish active from resolved infection. All patients with active HCV should receive DAA therapy (>95% SVR).
SBP diagnosis: PMN ≥250 cells/μL in ascitic fluid — treat immediately with ceftriaxone 2g IV without waiting for culture results. PMN count is the decision threshold, not culture positivity.
Albumin is mandatory in SBP treatment — 1.5 g/kg on day 1 + 1 g/kg on day 3 reduces hepatorenal syndrome and mortality by 30%. Do not omit.
SAAG ≥1.1 = portal hypertension as the cause of ascites. SAAG <1.1 = non-portal cause (malignancy, TB peritonitis, pancreatitis, nephrotic syndrome).
Acetaminophen toxicity: give N-acetylcysteine (NAC) immediately — even if >8 hours post-ingestion. NAC is beneficial up to 72 hours. Never withhold due to delayed presentation.
NAFLD/NASH: Most common cause of incidentally elevated LFTs in the US. Treatment: weight loss (>5–7% body weight reduces steatosis). Resmetirom (THR-β agonist) — first FDA-approved drug for MASH with fibrosis (2024).
Primary biliary cholangitis (PBC): Middle-aged woman + pruritus + fatigue + cholestatic LFTs + AMA positive. Treat with ursodeoxycholic acid (UDCA). AMA is the diagnostic antibody.
Primary sclerosing cholangitis (PSC): Beaded biliary tree on MRCP + UC association (70% of PSC patients have UC). p-ANCA positive. No effective medical therapy — transplant for end-stage.
Wilson's disease: Young patient + hepatitis + neuropsychiatric symptoms + Kayser-Fleischer rings + low ceruloplasmin. Treat with penicillamine or trientine. Liver transplant for acute liver failure.

Tier 1

Board Pearls — IBD, Lower GI & Colorectal

Crohn's vs UC · C. diff · CRC Screening · Diverticular Disease · Celiac

★★★ Highest Yield

Crohn's vs UC: the single most important distinction is depth and distribution. Crohn's = transmural, skip lesions, any GI tract segment, smoking worsens. UC = mucosal only, continuous from rectum, smoking is protective (slightly).
UC complications: toxic megacolon and colorectal cancer. CRC surveillance colonoscopy starts 8–10 years after UC diagnosis (every 1–2 years). Crohn's also increases CRC risk.
Crohn's perianal fistulas + skin tags + abscess = highly specific for Crohn's disease. Perianal disease is not a feature of UC.
Toxic megacolon: Colonic dilation >6cm + systemic toxicity. NO antidiarrheals, opioids, or anticholinergics — these precipitate it. IV steroids + IV antibiotics + surgical consult. Emergency colectomy if no improvement in 24–72h.
C. diff: do NOT give anti-motility agents (loperamide, diphenoxylate) — increases toxin retention and risk of toxic megacolon. Fidaxomicin is preferred over oral vancomycin for initial treatment (lower recurrence rate). Bezlotoxumab for recurrent C. diff.
CRC screening starts at age 45 for average-risk patients (USPSTF 2021 update, down from 50). Colonoscopy every 10 years OR annual FIT/FOBT. Earlier in Lynch syndrome (age 20–25), FAP (age 10–15), or family history.
Uncomplicated diverticulitis does NOT require antibiotics in immunocompetent patients — major 2023 paradigm shift (AVOD, DIABOLO, DIVER trials). Reserve antibiotics for complicated disease, immunocompromised patients, or failure to improve.
Celiac disease: test BEFORE starting a gluten-free diet. Anti-tTG IgA is the best initial test (high sensitivity + specificity). Confirm with duodenal biopsy (villous atrophy, crypt hyperplasia). Anti-tTG IgA false-negative in IgA deficiency — check total IgA first.
Fecal calprotectin: elevated in IBD, normal in IBS — most useful non-invasive test to distinguish the two when colonoscopy is not yet performed.
Colorectal cancer: FOBT positive in an asymptomatic patient → colonoscopy (not repeat FOBT, not FIT, not CT colonography first). Positive FOBT obligates colonoscopy regardless of age or risk.

Tier 1

Board Pearls — Biliary Tract & Pancreas

Cholelithiasis · Cholecystitis · Cholangitis · Pancreatitis · Pancreatic Cancer

★★★ Highest Yield

Charcot's triad = cholangitis (RUQ pain + fever + jaundice). Reynolds' pentad = Charcot's + AMS + hypotension = suppurative/life-threatening cholangitis. Emergent ERCP or biliary drainage — do not delay for additional imaging.
Acute cholecystitis: laparoscopic cholecystectomy within 24–72 hours of presentation is superior to delayed surgery — lower conversion rate, shorter hospital stay, fewer complications (Tokyo Guidelines 2018).
Murphy's sign: Inspiratory arrest during RUQ palpation due to pain — highly specific for acute cholecystitis. Sonographic Murphy's sign on ultrasound is even more specific.
Acalculous cholecystitis: Occurs in critically ill patients (ICU, post-major surgery, trauma, burns, TPN). No gallstones but gallbladder wall thickening + pericholecystic fluid on ultrasound. Higher mortality than calculous cholecystitis. Percutaneous cholecystostomy for unstable patients.
Courvoisier sign = palpable non-tender gallbladder + jaundice = malignant obstruction. In cholelithiasis, chronic inflammation prevents the GB from dilating. A distended, non-tender GB = cancer (pancreatic head, cholangiocarcinoma).
Acute pancreatitis diagnosis requires 2 of 3 Atlanta criteria: (1) Characteristic epigastric pain, (2) Lipase ≥3× ULN, (3) Characteristic CT findings. Do not require all three for diagnosis.
Prophylactic antibiotics in sterile pancreatitis are NOT indicated — three RCTs and meta-analyses show no benefit. Use only for confirmed infected necrosis.
Early enteral nutrition in pancreatitis is superior to NPO + TPN — reduces infectious complications and organ failure. Feed within 24–48h if tolerated.
Pancreatic cancer: new-onset diabetes in a thin elderly patient with weight loss = pancreatic cancer screen. New DM can be a paraneoplastic manifestation of pancreatic exocrine destruction. Get CT abdomen + CA 19-9.
Chronic pancreatitis triad: pain + steatorrhea + diabetes — the three consequences of progressive pancreatic destruction (exocrine and endocrine insufficiency). Pancreatic enzyme replacement (PERT) for steatorrhea.

Tier 1

Board Pearls — GI Pharmacology

PPI Interactions · IBD Biologics · C. diff Treatment · Antibiotic Traps · Drug-Induced GI Disease

★★★ Highest YieldMultiple Drug Traps

PPIs and clopidogrel interaction: Omeprazole and esomeprazole inhibit CYP2C19 → reduce clopidogrel activation. Use pantoprazole (minimal CYP2C19 interaction) in patients on clopidogrel after ACS/stenting.
Long-term PPI risks: Hypomagnesemia, C. diff risk, community-acquired pneumonia risk, bone fracture (reduced calcium absorption), vitamin B12 deficiency. Boards test hypomagnesemia specifically.
Metronidazole + alcohol = disulfiram-like reaction — nausea, vomiting, flushing. Warn patients strictly. Also applies to tinidazole.
C. diff treatment hierarchy: Non-severe: fidaxomicin (preferred) or oral vancomycin. Severe: oral vancomycin + IV metronidazole. Fulminant (ileus, shock): oral/rectal vancomycin + IV metronidazole ± emergent colectomy. Fecal microbiota transplant (FMT) for ≥3 recurrences.
LABA monotherapy contraindicated in asthma but NOT in COPD — this GI pearl: mesalamine (5-ASA) is first-line for UC but has NO role in Crohn's disease (not effective for small bowel or transmural disease).
IBD biologic selection: Anti-TNF agents (infliximab, adalimumab) for moderate-severe IBD. Check for latent TB (IGRA/TST) BEFORE starting any biologic — reactivation TB is a serious complication. Vedolizumab (gut-selective) preferred if TB risk is high.
Azathioprine/6-MP in IBD: Check TPMT (thiopurine methyltransferase) activity before starting — low TPMT activity → drug accumulation → severe myelosuppression. Also check for NUDT15 variant in Asian patients.
NSAIDs are the second most common cause of PUD (after H. pylori). They inhibit COX-1 → reduce prostaglandin synthesis → impair gastric mucosal protection. Add PPI prophylaxis for patients on chronic NSAIDs.
Rifaximin for IBS-D and hepatic encephalopathy: Non-absorbable antibiotic — safe to use repeatedly. Also used for small intestinal bacterial overgrowth (SIBO). Does NOT cause systemic antibiotic side effects.
Ursodeoxycholic acid (UDCA) for PBC: Slows disease progression. Does NOT work for PSC — trials showed no benefit and possible harm from UDCA in PSC.

Chapter Summary

Top 20 GI & Hepatology Board Traps

These are the exact questions that separate passing from failing — know every one.

20 Traps · All Domains

GERD — PPI Timing

PPIs must be taken 30–60 minutes BEFORE meals, not at bedtime or with food. Bedtime dosing reduces efficacy by ~50%.

PUD — Biopsy Rule

Gastric ulcers can be malignant → always biopsy. Duodenal ulcers are almost never malignant — biopsy not required.

H. pylori — PPI Washout

Stop PPIs ≥2 weeks before H. pylori testing (UBT or stool antigen) to avoid false negatives. Serology confirms prior exposure only — NOT active infection.

UGIB — Tranexamic Acid

Tranexamic acid is NOT recommended for GI bleeding (HALT-IT trial — no benefit, possible harm). Do not confuse with its role in trauma.

UGIB — Epinephrine Alone

Epinephrine injection alone is NOT adequate for peptic ulcer hemostasis. Always combine with a second modality — thermal coagulation or hemostatic clips.

GI Bleeding — Transfusion

Restrictive transfusion (Hgb <7 g/dL) in both variceal and non-variceal GI bleeding. Over-transfusion raises portal pressure and worsens variceal bleeding.

Cirrhosis — INR & FFP

INR does NOT predict bleeding risk in cirrhosis. Do NOT give FFP or vitamin K prophylactically before paracentesis or endoscopy in cirrhotic patients.

Ascites — SAAG

SAAG ≥1.1 g/dL = portal hypertension (cirrhosis, CHF, Budd-Chiari). SAAG <1.1 = non-portal causes. Replaces old transudate/exudate classification.

SBP — "250 and Treat"

PMN ≥250 in ascitic fluid = treat immediately. Albumin (1.5 g/kg day 1 + 1 g/kg day 3) is essential — not optional. Reduces mortality from 41% to 22%.

HE — Lactulose vs Rifaximin

Lactulose is first-line for acute HE. Rifaximin is added for secondary prophylaxis after recovery — NOT as first-line acute treatment alone.

HE — Protein Restriction

Protein restriction is NO LONGER recommended in hepatic encephalopathy. Adequate protein (1.2–1.5 g/kg/day) is required — restriction causes sarcopenia, which worsens HE.

HBV — Vaccinated vs Immune

Vaccinated = anti-HBs ONLY (no anti-HBc). Window period = anti-HBc IgM ONLY (HBsAg gone, anti-HBs not yet appeared). If anti-HBc present → natural infection, not just vaccine.

Liver Labs — Alcoholic Pattern

AST:ALT >2:1 with AST almost never >300 = alcoholic hepatitis. If AST >300, rethink — consider viral hepatitis, acetaminophen, or ischemic hepatitis.

Pancreatitis — Early Feeding

Early oral feeding within 24 hours if tolerated — "NPO until pain resolves" is outdated teaching that worsens outcomes. Enteral always preferred over TPN.

Pancreatitis — Prophylactic ABx

Prophylactic antibiotics are NOT indicated in severe or necrotizing pancreatitis with sterile necrosis. Only treat confirmed infected necrosis (gas on CT + clinical deterioration).

Biliary Pancreatitis — ERCP

ERCP in biliary pancreatitis is indicated ONLY for concurrent cholangitis or persistent biliary obstruction — NOT routinely for uncomplicated biliary pancreatitis.

Infected Necrosis — Step-Up

Infected pancreatic necrosis → antibiotics first (carbapenems), delay intervention ≥4 weeks to allow walled-off necrosis to mature. Step-up approach: endoscopic drainage before surgery.

IBS — Positive Diagnosis

IBS is a POSITIVE diagnosis based on Rome IV criteria — NOT a diagnosis of exclusion. Do not order a battery of tests before diagnosing IBS when there are no alarm features.

Diverticulitis — No Routine ABx

Antibiotics are NOT routinely required for uncomplicated acute diverticulitis in immunocompetent patients (AVOD, DIABOLO, DIVER trials — 2023 paradigm shift). Reserve for complicated disease.

Celiac — Test Before the Diet

Do NOT start gluten-free diet before testing for celiac — GFD normalizes anti-tTG IgA serology and duodenal biopsy, making diagnosis impossible. Always test while on gluten-containing diet.

Quick-Scan Reference — The Numbers That Win Points

TRANSFUSION THRESHOLDS

Hgb <7 g/dL (all GI bleeding)
Hgb <8–9 if active CVD

SAAG CUTOFF

≥1.1 = portal HTN
<1.1 = non-portal

SBP THRESHOLD

PMN ≥250 = treat NOW
Albumin 1.5 g/kg day 1

H. PYLORI TESTING

Stop PPI ≥2 weeks before
Wait ≥4 weeks post-ABx

CRC SCREENING START

Age 45 (average risk)
Age 20–25 (Lynch syndrome)

PANCREATITIS DIAGNOSIS

Lipase ≥3× ULN (not amylase)
2 of 3 Atlanta criteria

⬡ Closing Statement

"GI on the PANCE rewards the student who knows the traps — the PPI timing question, the H. pylori test question, the SBP albumin question, the HBV window period. These are not random. They are the exact clinical decision points where real patients get mismanaged. Master the patterns, know the numbers, and recognize the anti-pattern that turns a board question into a learning moment."

— Rajiv Choudhary, MD, MPH

GI & HepatologyBootcamp Syllabus

You've seen the preview.Unlock all 22 GI & Hepatology topics.

GI & Hepatology
Bootcamp Syllabus

You've seen the preview.
Unlock all 22 GI & Hepatology topics.