APT: Liver

This week we will be discussing the Liver and Bile Collecting system. Please review NEJM review articles on cirrhosis, acute liver failure, and ACG clinical guidelines for LFT interpretation/work up to help prepare.


Approach to Liver chemistries:

ALT: 33 (males), 25 (females), ALP: 115 (males), 100 (females)

Hepatocellular: ALT and AST both up

Cholestatic: ALP up and also direct hyperbilirubinemia

Infiltrative: ASLT up without significant bilirubin or AST or ALT elevation

Non-hepatic: Isolated AST elevated, indirect hyperbilirubinemia


Any degree of AST/ALT elevated:

  • meds/toxins (aceteaminophen, certain abx, INH, MTX, NSAIDs, heparin, amiodarone, steroids, augment, sulfa drugs, allopurinol, etc)

  • Alcohol related (alcoholic hepatitis usually >2:1 AST:ALT ratio)

  • viral infections (Hep A-E, EBV, CMV, VZV, HSV)

  • Sepsis /ischemia

  • Biliary obstruction (mixed picture)

  • NAFLD (usually AST and ALT elevated but <4x ULN)

If above: Workup includes, but not limited to:

  • stop offending medications/toxins

  • viral hepatitis serologies

  • RUQ US (steatosis, cirrhosis, fibroscan)

  • ANA, ASMA, LKM-1, IgG, Ceruloplasmin, urinary copper, Fe/TIBC >45%, ferritin >200,

Extreme elevation (AST/ALT >1000s, indicates some acute process)

  • Ischemia (Shock, cardiac arrest, Budd-Chiari, usually AST/ALT goes up first then bilirubin increases)

  • Meds/toxins (acetaminophen toxicity)

  • Acute viral infection (Hep A-E, consider HBV reactivation)

  • autoimmune hepatitis

  • acute biliary obstruction

If above, workup includes, but not limited to

  • INR, assess for hepatic encephalopathy, acute liver injury/failure

  • stop offending meds/toxins, consider activated charcoal, N-acetylcysteine

  • viral serologies

  • RUQ US with dopplers

Cholestatic injury pattern (Increased ALP and biliriubin)

  • Biliary obstruction (Choledocholithiasis, malignancy, primary sclerosis cholangitis, chronic pancreatitis w/ strictures)

  • intrahepatic cholestasis: Medications (penicillin, cephalosporins, anabolic steroids, bactrim, TPN, sepsis, primary biliary cholangitis (PBC)

If above, workup with include, but not limited to

  • RUQ US for obstruction

  • MRCP or ERCP

  • +/- liver biopsy

Infiltrative pattern (primarily ALP elevation)

  • sarcoidosis or other granulomatosis (Tb)

  • Malignancy (lymphoma, mets to liver, HCC)

  • Amyloidosis

  • abscess

If above, workup includes, but not limited to

  • GGT, imaging with RUQ US or CT, MRCP

  • Consider SPEP + IgG4

  • +- liver biopsy

Acute Liver Failure

King’s College Criteria

  • Acetaminophen induced liver failure: pH <7.3, or ALL 3 of INR > 6.5, Cr > 3.4, grades 3-4 Hepatic encephlopathy

  • All other causes of ALF: INR >6.5 OR 3/5 of the following: age <10 or >40, Tbili >17, INR >3.5, time from jaundice to encephalopathy >7d, unfavorable etiology (Seronegative hepatitis, DILI, Wilson’s)

Decompensated Cirrhosis



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APT: Endocarditis

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APT: COPD