GI Liver, Biliary, and Pancreatic Disorders 1 — Questions and Answers
Question 1: Which liver enzyme is considered most specific for hepatocellular damage?
- AST (aspartate aminotransferase)
- ALT (alanine aminotransferase) (Correct answer)
- Alkaline phosphatase
- GGT (gamma-glutamyl transferase)
Correct answer: ALT (alanine aminotransferase)
ALT is more liver-specific than AST because AST is also found in muscle, heart, and kidneys, whereas ALT is predominantly hepatic.
Question 2: What is the most common cause of acute pancreatitis in the United States?
- Chronic alcohol use
- Gallstones (Correct answer)
- Hypertriglyceridemia
- Medication-induced
Correct answer: Gallstones
Gallstones are the leading cause of acute pancreatitis in the US, accounting for approximately 40–70% of cases.
Question 3: Which antibody is most characteristic of primary biliary cholangitis (PBC)?
- Anti-smooth muscle antibody (ASMA)
- Anti-mitochondrial antibody (AMA) (Correct answer)
- Anti-nuclear antibody (ANA)
- pANCA
Correct answer: Anti-mitochondrial antibody (AMA)
Anti-mitochondrial antibodies (AMA), particularly M2 subtype, are present in over 90% of PBC cases and are highly specific.
Question 4: In hepatic encephalopathy, which neurotoxic substance primarily accumulates due to failed hepatic clearance?
- Bilirubin
- Ammonia (Correct answer)
- Urea
- Creatinine
Correct answer: Ammonia
Ammonia, normally converted to urea by the liver, accumulates in hepatic failure and crosses the blood-brain barrier, causing encephalopathy.
Question 5: Which is the most common primary malignancy of the liver in adults?
- Cholangiocarcinoma
- Hepatocellular carcinoma (HCC) (Correct answer)
- Angiosarcoma
- Hepatoblastoma
Correct answer: Hepatocellular carcinoma (HCC)
Hepatocellular carcinoma (HCC) accounts for approximately 75–85% of primary liver cancers and is strongly associated with cirrhosis and viral hepatitis.
Question 6: On MRCP or ERCP, primary sclerosing cholangitis (PSC) characteristically shows which finding in the bile ducts?
- A beaded, multifocal stricture pattern (Correct answer)
- Smooth diffuse dilation of the common bile duct
- Single dominant stricture at the hilum
- Intrahepatic gallstones
Correct answer: A beaded, multifocal stricture pattern
PSC produces multifocal strictures alternating with normal or dilated segments, creating the classic 'beaded' appearance on cholangiography.
Question 7: The MELD score used to prioritize liver transplant candidates incorporates which combination of laboratory values?
- ALT, AST, and albumin
- Bilirubin, INR, and creatinine (Correct answer)
- Bilirubin, albumin, and prothrombin time
- AST, ALT, and platelet count
Correct answer: Bilirubin, INR, and creatinine
The MELD score is calculated from serum bilirubin, INR, and creatinine (with sodium added in MELD-Na), reflecting hepatic synthetic function and renal status.
GI Liver, Biliary, and Pancreatic Disorders 1
Which liver enzyme is considered most specific for hepatocellular damage?