Study guide
High-Yield GI & Nutrition for the PANCE
The gastrointestinal system and nutrition is the single largest domain on the current NCCPA PANCE blueprint (~9-10% of items), making it one of the highest-yield areas to master. This guide covers the most-tested esophageal, gastric, hepatobiliary, pancreatic, intestinal, and anorectal disorders with board-current diagnostics and first-line therapy.
Esophagus, Stomach, GERD & PUD
- ◆GERD: diagnose clinically and start an empiric PPI trial. Alarm features (dysphagia, odynophagia, weight loss, GI bleeding, anemia, new onset age >60) mandate EGD. Barrett esophagus (intestinal metaplasia) requires surveillance endoscopy given adenocarcinoma risk.
- ◆PUD: H. pylori and NSAIDs are the top two causes. Test with urea breath test or stool antigen (hold PPI 1-2 weeks, antibiotics/bismuth 4 weeks beforehand). Per the 2024 ACG guideline, optimized bismuth quadruple therapy (PPI + bismuth + tetracycline + a nitroimidazole such as metronidazole) x14 days is the preferred first-line regimen; clarithromycin triple therapy is NO LONGER recommended empirically and should be used only when local resistance is documented <15% or susceptibility is confirmed. Rifabutin triple and potassium-competitive acid blocker (vonoprazan)-based regimens are additional options.
- ◆Duodenal ulcer pain classically improves with food; gastric ulcer pain worsens with food. Biopsy gastric ulcers to exclude malignancy and confirm eradication after treatment.
- ◆Zollinger-Ellison (gastrinoma): refractory or multiple ulcers plus diarrhea and elevated fasting gastrin; associated with MEN1. Achalasia: dysphagia to BOTH solids and liquids, bird-beak on barium swallow, manometry confirms (absent peristalsis, failed LES relaxation).
- ◆Esophageal variceal bleed: octreotide + prophylactic IV ceftriaxone + endoscopic band ligation; nonselective beta-blocker for secondary prevention. Boerhaave = transmural rupture (surgical emergency, pneumomediastinum); Mallory-Weiss = mucosal tear after retching, usually self-limited.
Hepatobiliary Disease
- ◆Cholelithiasis: RUQ pain after fatty meals; ultrasound is first-line. Acute cholecystitis: positive Murphy sign with wall thickening/pericholecystic fluid (HIDA if US equivocal); treat with antibiotics plus early laparoscopic cholecystectomy.
- ◆Choledocholithiasis/ascending cholangitis: Charcot triad (RUQ pain, fever, jaundice); Reynolds pentad adds hypotension and altered mental status. Treat with antibiotics plus urgent ERCP for biliary decompression.
- ◆Hepatitis B serologies: HBsAg = active infection; anti-HBs = immunity (vaccine or resolved); isolated anti-HBc IgM = window period; HBeAg = high infectivity. Hepatitis C is the leading cause of cirrhosis/HCC and is curable with direct-acting antivirals; USPSTF recommends one-time screening in all adults 18-79.
- ◆Cirrhosis complications: portal hypertension (varices, ascites), spontaneous bacterial peritonitis (ascitic PMN >=250; treat with cefotaxime + albumin), and hepatic encephalopathy (treat with lactulose +/- rifaximin). Screen for HCC with US +/- AFP every 6 months.
- ◆Alcoholic hepatitis: AST:ALT ratio >2:1, both usually <300-500. Autoimmune/PBC: antimitochondrial antibody in primary biliary cholangitis (treat with ursodeoxycholic acid). Hemochromatosis: elevated ferritin and transferrin saturation; Wilson disease: low ceruloplasmin, Kayser-Fleischer rings in young patients.
Pancreas & Small/Large Bowel
- ◆Acute pancreatitis: 2 of 3 criteria (characteristic epigastric pain radiating to back, lipase >3x upper limit, imaging). Gallstones and alcohol are the top causes; treat with goal-directed (moderate) IV fluid resuscitation, analgesia, and early enteral nutrition. CT for complications (necrosis, pseudocyst).
- ◆IBD: Crohn = transmural, skip lesions, mouth-to-anus, non-caseating granulomas, fistulas; UC = continuous mucosal inflammation from rectum, bloody diarrhea, increased colon cancer risk. Both may respond to 5-ASA/biologics; toxic megacolon is a UC emergency.
- ◆Celiac disease: anti-tissue transglutaminase (tTG) IgA is first-line serology (check total IgA); confirm with duodenal biopsy showing villous atrophy; treat with lifelong gluten-free diet. Dermatitis herpetiformis is the skin manifestation.
- ◆Diverticulitis: LLQ pain, fever; CT confirms. Uncomplicated cases can be treated outpatient (antibiotics may be omitted in selected immunocompetent patients with mild, uncomplicated disease); avoid colonoscopy acutely, perform 6-8 weeks after resolution. C. difficile: first-line is oral fidaxomicin (preferred) or oral vancomycin; metronidazole is now reserved for when those are unavailable.
- ◆Bowel obstruction: SBO from adhesions/hernias (bilious vomiting, air-fluid levels); large bowel from cancer/volvulus. Acute mesenteric ischemia = pain out of proportion to exam, often AFib/embolic. Appendicitis: periumbilical pain migrating to RLQ (McBurney), CT confirms, appendectomy.
Colorectal Neoplasia & Anorectal
- ◆Colorectal cancer screening (USPSTF): begin at age 45 for average-risk adults through 75. Options include colonoscopy every 10 years or annual FIT. Left-sided cancers present with obstruction/change in caliber; right-sided with iron-deficiency anemia and occult bleeding.
- ◆Iron-deficiency anemia in a man or postmenopausal woman is colon cancer until proven otherwise; work up with colonoscopy. Adenomatous (especially villous) polyps carry the highest malignant potential.
- ◆Hemorrhoids: internal are painless bright-red bleeding; external thrombosed are acutely painful. Treat with fiber, sitz baths, topical therapy; excision if thrombosed within 48-72 hours. Anal fissure: severe pain with defecation, posterior midline; treat with fiber, sitz baths, topical nifedipine or nitroglycerin.
- ◆Perianal abscess/fistula: incision and drainage is definitive for abscess; fistula-in-ano often follows. Pilonidal disease occurs in the sacrococcygeal region of young men.
GI Bleeding, Hernias & Nutrition
- ◆Upper GI bleed (proximal to ligament of Treitz): melena, hematemesis, elevated BUN:Cr ratio; PUD is the most common cause. Resuscitate, start IV PPI, and perform EGD within 24 hours. Lower GI bleed: hematochezia, most commonly diverticulosis or angiodysplasia.
- ◆Hernias: indirect inguinal (lateral to inferior epigastric vessels, most common overall) vs direct (medial). Incarcerated/strangulated hernias (irreducible, tender, systemic signs) require emergent surgery.
- ◆Vitamin deficiencies: B12 (megaloblastic anemia + neuro deficits, seen post-ileal resection/pernicious anemia); thiamine/B1 (Wernicke-Korsakoff in alcoholics; give thiamine before glucose); vitamin D (rickets/osteomalacia); vitamin K (coagulopathy).
- ◆Infectious diarrhea pearls: bloody diarrhea from EHEC O157:H7 - avoid antibiotics (HUS risk); Campylobacter is the most common bacterial cause and can precede Guillain-Barre; Giardia causes greasy foul diarrhea after camping (treat with tinidazole/metronidazole).