Viral Hepatitis Australian Family Physician Vol. 30 No.5, May 2001 Presented by 郭詠怡 Date presented:25/8/2003

Causes of hepatitis incubation (days): HAV: Enteric HBV: Blood borne HCV: Blood borne HDV: Blood borne HEV: Enteric HGV: Blood borne unknown

HAV and HEV: with water/ food outbreaks ( travelling to developing world). No chronic carriers HBV and HCV: STD, injecting drug use, occupational exposure in health care worker, causing acute and chronic hepatitis, carriers,, hepatocellular carcinoma HDV: super infection or coinfection with HBV HGV: possibly causes transfusion hepatitis

Other causes of hepatitis Other viruses: Herpes viruses -CMV -EBV Yellow fever virus Other causes: nonviral infections, drugs, alcohol, anoxic liver injury

Needlestick exposure Collection nurse (recipient) Skin unbroken? Gloves worn? Had blood been drawn or was sterile needle involved? Did injury result in blood being drawn? Patient (source) Injection drug use Sexual preference Blood ransfusions Overseas travel Migration history

Tests to order after needlestick exposure On the patient (source) HIV Ab, HBsAg, HCV Ab On the nurse (recipient) HBsAb, storage of serum

Main clinical presentations in viral hepatitis HAV: --acute hepatitis in adults—(75% symptomatic, but self limiting); children usually asymptomatic --fulminant hepatitis (rare) HBV: --acute hepatitis (mostly self limiting,50% asymptomatic) --fulminant hepatitis (specially if coinfected with HDVor concurrent HCV --chronic hepatitis leading to carrier state 5-10%

Main clinical presentations in viral hepatitis HCV: --chronic hepatitis leading to carrier state 50-70% --acute hepatitis (75% asymptomatic) --fulminant hepatitis (uncommon, seen with concurrent HBV HDV: --acute exacerbation in chronic hepatitis B (HDV superinfection) --fulminant hepatitis ( if coinfected with HBV) --chronic hepatitis leading to carrier state (variable 5-70%) HEV: --acutehepatitis (usually self limiting) -- fulminant hepatitis (rare, but seen in pregnant women)

Hepatitis serology clinical situation tests to order HAV acute hepatitis HAV IgM HBV see next slide HCV acute hepatitis HCV Ab, HCV PCR chronic carrier HCV Ab HDV(only coinfection or HBsAG, HBcIgM, if HbsAg+) superinfection HDV Ab HEV acute hepatitis HEV Ab HGV HGV PCR

HBV serology Late incubation period: HBsAg Acute hepatitis: HBsAg, HBcIgM, HBcAb Total, HBeAb, HBV DNA Window period: HBcIgM, HBcAb Total, HBV DNA Healthy carrier: HBsAg, HBcAb Total, HBeAb Chronic carrier/ replicative: HBsAg, HBcAb total, HBeAg, HBV DNA Recovery/immunity: HBcAb Total Recent vaccination: HBsAb

Treatment for viral hepatitis Virus Antiviral A,E,G not available B,D interferon+lamivudine C interferon+ribavirin

Prevention of viral hepatitis Virus Vaccine Schedule A Havrix or 2 doses at 0 VAQTA and 6 months B,D Engerix B 3 doses at 0,1,6 or HBVax II months

Summary of important points Most cases of viral hepatitis are self limiting or asymptomatic Epidermiological hisory is helpful to determine which tests to order There are a number of markers for HBV, used for different stages of the disease. Vaccination can prevent infection with certain hepatitis viruses, eg. HAV and HBV The role of some new viruses thought to cause hepatitis is controversial