About This Page
This is a clinician-written, evidence-based summary aligned to the USMLE Step 2 CK Content Outline. It is intended for medical students preparing for USMLE Step 2 CK. Management reflects current ACC/AHA, USPSTF, and APA guidelines. Always cross-reference with UpToDate, institutional protocols, and clinical judgment.
Key points
- Diagnosis requires 2 of 3: characteristic pain, lipase/amylase >=3x ULN, or imaging findings
- Most common causes in the US: gallstones and alcohol
- Initial management: lactated Ringer fluids, analgesia, antiemetics, early oral feeding as tolerated
- No prophylactic antibiotics for sterile necrosis or uncomplicated pancreatitis
- ERCP within 24 h only when gallstone pancreatitis is complicated by cholangitis or persistent biliary obstruction
Overview
Acute pancreatitis is pancreatic inflammation from premature activation of digestive enzymes. Gallstones transiently obstruct the ampulla; alcohol causes toxic acinar injury and ductal changes. Severity ranges from mild interstitial pancreatitis to necrotizing pancreatitis with organ failure.
Epidemiology
Acute pancreatitis is a common GI hospitalization. Gallstones are the most common cause overall, with alcohol second. Other causes include hypertriglyceridemia, ERCP, medications, hypercalcemia, trauma, autoimmune disease, and pancreatic malignancy.
Clinical Features
Symptoms
Epigastric pain radiating to the back
Nausea, vomiting, anorexia
Pain may improve leaning forward
Steatorrhea and weight loss in chronic disease
Fever, hypotension, oliguria, hypoxemia, jaundice, or severe persistent pain
Signs
Epigastric tenderness
Tachycardia, dehydration, ileus
Cullen or Grey Turner sign in hemorrhagic pancreatitis
Shock, hypoxemia, peritonitis, or jaundice
Investigations
First-line
Serum lipase>=3x upper limit supports acute pancreatitis; may be normal in chronic burnt-out disease
CMP, CBC, BUN, hematocrit, calcium, triglyceridesSeverity and etiology assessment
RUQ ultrasoundEvaluate gallstones in acute pancreatitis
Second-line
Contrast CT abdomenDiagnostic uncertainty or failure to improve after 48-72 h
MRCP/EUSDuctal disease, stones, malignancy, chronic pancreatitis evaluation
Fecal elastaseLow value supports exocrine insufficiency in chronic pancreatitis
Specialist
ERCPTherapeutic for cholangitis or persistent biliary obstruction, not routine pancreatitis
IgG4If autoimmune pancreatitis suspected
Management
ACG Guideline: Acute Pancreatitis 20241
Acute management
- Moderately aggressive lactated Ringer fluids with reassessment
- Opioid analgesia and antiemetics
- Early oral feeding as tolerated in mild disease
- No prophylactic antibiotics for sterile necrosis
2
Cause-specific
- Same-admission cholecystectomy for mild gallstone pancreatitis
- ERCP within 24 h if cholangitis
- Treat alcohol use disorder or severe hypertriglyceridemia
3
Chronic management
- Alcohol and smoking cessation
- Pancreatic enzyme replacement with meals for steatorrhea
- Fat-soluble vitamin replacement and diabetes monitoring
- Endoscopic/surgical therapy for obstructing stones or strictures
Complications
- Acute: Pseudocyst, necrosis, infected necrosis, ARDS, AKI, hypocalcemia.
- Chronic: Exocrine insufficiency, diabetes, pseudocyst, biliary obstruction, pancreatic cancer risk.
USMLE Step 2 CK Exam Tips
- 1Acute pancreatitis diagnosis is 2 of 3 criteria
- 2Lipase level does not track severity
- 3Gallstone pancreatitis + cholangitis = ERCP
- 4No prophylactic antibiotics for sterile necrosis
- 5Early feeding is preferred in mild acute pancreatitis
- 6Pancreatic calcifications + steatorrhea = chronic pancreatitis
- 7Fecal elastase supports pancreatic exocrine insufficiency
Put your reading into practice
Checking available topic practice…
Choose USMLE Step 2 CK questions from the existing bank. General exam practice covers your selected topics; it is not filtered to this article. Your usual question-bank access applies.
Choose USMLE Step 2 CK practiceAfter your session, return to this section to revisit the reading and choose your next review.
regional clinical guidance
Acute Pancreatitis: guidance by region
Recommendations, thresholds and pathways can differ. Open the page written for the jurisdiction you need.
Verified Sources & References
related resources
Save your place and choose what comes next
Gastroenterology & Hepatology · Article 9 of 25