Viral Hepatitis And Acetaminophen Hepatotoxicity Flashcards
Course of hepatitis?
- Constitutional symptoms, arthralgias, myalgias, pharyngitis
- Visible jaundice, enlargement of the liver, dark urine
Transaminase levels more than 1000 may lead to? Causes?
Extensive hepatic necrosis. Causes: toxic injury, viral hepatitis, ischemia
Hepatitis A and E are transmitted by?
Fecal oral route. By contaminated food or water and daycare
Most common cause of acute viral hepatitis in the US?
Hepatitis A
Worst-case scenario after hepatitis A infection?
A few patients get fulminant disease resulting in liver failure
Worst-case scenario after hepatitis E infection?
Pregnant women can develop severe hepatic necrosis and fatal liver failure
Adult vs Newborns infected with hepatitis B. Chance of chronic infection?
5% versus 90%
Hepatitis most likely to be sexually-transmitted?
B (C to lesser extent)
Hepatitis transmitted by blood transfusions or IV drug use?
C
Fulminant hepatic failure is usually caused by? Prognosis?
Hepatitis B and D or drug-induced. Poor prognosis.
How to diagnose hepatitis A,B,C?
A: Anti-hepatitis A IgM
B: hepatitis B surface antigen
C: hepatitis C RNA assay or anti-hepatitis C antibody
Window period?
Interval between the disappearance of HBsAg and the appearance of anti-HBsAb
Describe hepatitis A vaccine. Efficacy?
Two doses given six months apart. Exceeds 90%.
Postexposure prophylaxis to contacts of patient with hepatitis A or B?
If not vaccinated: Hepatitis A/B immunoglobulin along with the first injection of the vaccine
Hepatitis B vaccine: delivery and efficacy?
Given in three doses over six months. Over 90%.
Hepatitis C immunization and postexposure prophylaxis?
None
Treatment for patients with chronic hepatitis B? B or C?
Lamividine. Interferon
Hepatotoxicity by acetaminophen results after acute ingestion of?
10 g or more (lower in patients with existing liver disease especially those who abuse alcohol)
Acetaminophen metabolism? Neutralization? Increased risk of injury if?
Metabolized by P450 enzymes. Produces toxic metabolite which is detoxified by glutathione.
Increasing injury:
- P450 induction (from alcohol or phenobarbital)
- Decreases in glutathione from alcoholism, malnutrition or AIDS
Treatment of acetaminophen toxicity? Mechanism of treatment? Duration of treatment?
Decontamination with charcoal and N-acetylcysteine. N-acetylcysteine provide cysteine to replenish glutathione stores. Start within the first 10 hours to prevent liver damage continue for 72 hours.
