- may cause outbreaks from contaminated food/water
- Causes 50% of all acute viral hepatitis in U.S.
- virus found in feces > or = 2 weeks before onset of symptoms, so greatest risk of transmission is before sx are even present
Diagnosis of Hepatitis A
Lab: Anti-HAV IgM (positive by the time sx start, disappears at 14 weeks), Anti-HAV IgG (at 4 weeks, then forever)
Hepatitis A symptoms
- start 4-6 weeks after exposure
- Many may be asymptomatic, but exposure causes Anti-HAV IgG positive result, GIVING PROTECTION.
- 1% will have fulminant hepatic failure
- Decrease appetite
- smokers lose taste for cigarettes
- Pre-icteric (prodromal) phase: up to 3 weeks, pt. most infectious.
- Icteric phase: lasts 2-4 weeks
- Post-icteric phase: avg 2-4 months
P.E. of Hepatitis A
Jaundice (at 2 weeks post-exposure)
Elevated LFT's, bilirubin > 10, Alk.phos., GGT
Treatment of Hepatitis A
No treatment available
99% get better
Prevention of Hepatitis A
Hep.A vaccine (protective after 4 weeks; give to chronic hepatitis pts. that are anti-HAV negative)
Immune globulin against hepatitis A (provides temporary passive immunity for 6-8 weeks; effective if given w/in 1-2 weeks after exposure) (Given to all close contacts who are Anti-HAV negative). Can be given prophylactically before travel.
Pt. education in Hepatitis A
All contacts need to get tx prophylactically.
Avoid ETOH, NSAIDS, acetaminophen.
Infection control precautions in hospital.
- acute or chronic
- spread percutaneously (IV drug use, needlestick injuries)
HBsAg - Hep.B surface antigen (present by the time symptoms arise)
Anti-HBs/HBsAB - antibody to Hep.B surface antigen (IMMUNITY FROM HEP.B.)
Anti-HBc (IgM, IgG) - antibodies to Hep.B core antigen
Symptoms of Hep.B.
Same manifestations as Hep.A.
30% have no symptoms
10% will develop chronic hepatitis B
Preventing Hep.B spread
HBIG: Hepatitis B immune globulin - given to anyone who is exposed including infants born to mothers positive for HBsAg.
Hepatitis B Vaccine - recommended for all newborns & adolescents, anyone at high risk for hep.B. (IV drug users, close contacts w/ hep.B carrier), postexposure prophylaxis, 3 injections, ALL HEALTHCARE WORKERS, HD pts.
Hepatitis B complications
chronic Hep.B. infection can lead to:
- hepatocellular carcinoma
Only for chronic Hep.B. (active virus for > 6 months)
Alpha interferon for 4 months effective in 30%.
Acute infection is usually asymptomatic.
85% of Hep.C. becomes chronic
20% of these will progress to cirrhosis
20% will develop liver fx &/or hepatocellular carcinoma
May take 20-30 years to progress to cirrhosis or cancer.
Hep.C. Mode of Transmission
Percutaneous exposure (blood transfusion, IV drug use, HD, tatooing, body piercings, inh. cocaine, can be sexually).
10% no identified cause.
Symptoms of Chronic Hep.C.
Most asymptomatic, found by elevated LFT's.
FATIGUE most common symptom.
RUQ discomfort, then cirrhosis when progresses.
Diagnosis of Hep.C.
Then, check anti-HCV (ELISA assay)
**MOST SENSITIVE TEST** HCV RNA PCR measures actual amount of virus in blood
Treatment of Hep. C.
Pegylated interferon weekly SQ injections + Ribavirin PO