Block 1: Drug induced Liver Injury/Cirrhosis Flashcards
What is the liver function?
- Bile production
- Fat-soluble vitamin storage and metabolism (ADEK)
- Drug metabolism
- Billirubin metabolism
- Produces proteins for blood clotting and osmotic pressure
- Metabolizes nutrients from food to produce energy prn
Most common DILI medications?
- Alcohol
- Antibiotics
- Antiseizure
- APA
Most common cause of drug withdrawal, difficult to detect
Fisk facotors of DILI?
- Older age
- Females with severe hepatotoxicity
- Males with azathioprine, anabolic steroids, amox-clav
- Genetic polymorphisms
- DDI
- Livertox score
How do you diagnose DILI?
Patient with one of the following:
1. AST or ALT >5x ULN or ALP >2x (or fromt baseline) on 2 separate occasions
2. Total serum bilirubin >2.5 mg/dL with elevated AST, ALT or ALP
3. INR >1.5 with elevated AST, ALT, ALP
What are the elemetns that a drug might cause liver injury?
- Drug exposure preceded injury
- Causes of liver disease are excluded
- Drug discontinuation leads to improvement in the liver injury
- Rapid and severe recurrence occurs if there is repeated exposure to the drug (rechallenge)
Types of hepatotoxic medications classes?
- Antibiotics/Antimicrobial
- Immunosuppressive
- Birth control
- NSAIDs
- Antineoplastic
- Antiepiletic
MOA of APA toxicity?
What is the tx of APAP toxicity?
- NAC: most effective within 8hr of ingestion
N-acetylcysteine?
MOA, Forms, Monitoring
MOA: repletes glutathione reserves by providing cysteine, an essential precursor to glutathione production (binds to toxic metabolites and scavenges free radicals)
Forms: IV or Oral (rotten eggs)
Tx continues untils APAP levels are undetectable, PT/INR near normal, Encepalopathy resolved, transaminase levels trending down
What are liver chemistries?
Markers of injury not function
What is on a liver comprehensive metabolic panel?
- ALT
- AST
- ALP
- Bilirubin
- Albumin
What is cirrhosis?
- Caused by chronic liver injury
- Regenerative nodules surrounding dense fibrotic material
- Impacts portal BF, hepatocyte perfusion, hepatic synthetic functions
- Leads to portal HTN. varices, variceal bleeding, ascites, infection, encephalopathy, and hepatocellular carcinoma
What is varices?
Enlarged esophagus and stomach veins
Common causes of cirrhosis?
- Alcoholism
- Chronic Hep C
- NAFLD