Hepatitis

INTRODUCTION

Acute viral hepatitis may be caused by hepatitis A, B, C, D and E, and less commonly by CMV and EBV. These can cause severe liver disease (esp. hepatitis B and C) from end-stage liver failure to hepatocellular carcinoma. A and D are spread by the faecal–oral route, B and C from blood and possible other body fluids. See also 326–8.

Diagnostic markers for acute hepatitis

• Hepatitis A: IgM anti-HAV (Ab)

• Hepatitis B: surface antigen (HBsAg)

• Hepatitis C: anti-HCV (Ab)

• IgM antibodies = recent infection

• IgG antibodies = previous exposure

HEPATITIS A

Features

• Fever, malaise, anorexia, nausea, arthralgia → jaundice

• Recovery usu. in 3–6 wks—self-limiting

• Sometimes a subclinical illness

• No carrier state

• Does not cause chronic liver disease

• Fulminant hepatitis with coma and death is rare

• LFTs and viral markers confirm diagnosis

Serology

• IgM anti-HAV = active infection

• IgG antibodies = immunity

Treatment

• Rest as appropriate

• Avoid sedatives, NSAIDs

• Cease alcohol until LFTs normal

• Cease OCP

• Fat-free diet

• Advise on infection control

Prevention

• Sanitary health measures

• 2 dose primary vaccine 0 → 6–12 mth

HEPATITIS B (HBV)

Features

• Similar clinical presentation to hepatitis A but arthralgia and uriticaria more common

• Transmission by blood spread, sex, perinatal spread, percutaneous

• 5% become chronic carriers but

• 95% with infant-acquired HBV → carriers

• 15–40% of carriers → cirrhosis

• LFTs and viral markers confirm diagnosis

HBV antigens of virus particle

• HBsAg = surface antigens—a marker of viral replication and infection

• HBcAg = inner core antigens—a marker of exposure rather than vaccination

• HBeAg = a soluble protein from pre-core and core → high-level infection and infectivity

Antibodies develop to each of these (see Fig. H10).

Serology guidelines

• HBsAg = acute/persistent infection (the main investigation for HBV)

• Anti-HBs = past infection and immunity

• HBeAg = highly infective

• HBV DNA = circulating and replicating virus

• Anti-HBc IgM = recent infection and earliest indicator

• Anti-HBc IgG = past infection

• Anti-HBe = seroconversion

Interpretation

• HBsAg = diagnosis and/or carrier

  • – if +ve do full viral profile

Progress is monitored 6–12 mthly with HBeAg, HBV DNA and LFTs:

• HBsAg –ve + HBV DNA + anti-HBe = resolving

• as above + anti-HBs = ...