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 15-60

HBV: Blood borne 45-160

HCV: Blood borne 14-120

HDV: Blood borne 42-180

HEV: Enteric 15-64

HGV: Blood borne unknown

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

Other causes of hepatitis

Other viruses: Herpes viruses -CMV -EBV Yellow fever virus Other causes: nonviral infections, drugs, al

cohol, 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 useSexual preferenceBlood ransfusionsOverseas 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% asympto

matic) --fulminant hepatitis (specially if coinfected with HD

Vor 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 superinfectio

n) --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 orderHAV acute hepatitis HAV IgMHBV see next slideHCV acute hepatitis HCV Ab, HCV PCR chronic carrier HCV AbHDV(only coinfection or HBsAG, HBcIgM,

if HbsAg+) superinfection HDV Ab HEV acute hepatitis HEV AbHGV HGV PCR

HBV serology

Late incubation period: HBsAgAcute hepatitis: HBsAg, HBcIgM, HBcAb Total, HBeAb, HBV DNAWindow period: HBcIgM, HBcAb Total, HBV DNAHealthy carrier: HBsAg, HBcAb Total, HBeAbChronic carrier/ replicative: HBsAg, HBcAb total, HBeAg, HBV DNARecovery/immunity: HBcAb TotalRecent 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 asymptomaticEpidermiological hisory is helpful to determine which tests to orderThere 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 HBVThe role of some new viruses thought to cause hepatitis is controversial