Acute viral hepatitis

Hepatitis can be caused by the hepatitis viruses A, B, C, D, or E. The D and E forms are rare in the United Kingdom. A large proportion of infections with hepatitis viruses of all types are asymptomatic or result in anicteric illnesses that may not be diagnosed as hepatitis. Hepatitis A virus causes a typically minor illness in childhood, with more than 80% of cases being asymptomatic. In adult life infection is more likely to produce clinical symptoms, although only a third of patients with acute hepatitis A infections are jaundiced. Infections with hepatitis B and C viruses are also usually asymptomatic except in intravenous drug users, in whom 30% of hepatitis B infections are associated with jaundice.

In the preicteric phase, patients often have non-specific systemic symptoms together with discomfort in the right upper quadrant of the abdomen. An illness resembling serum sickness occurs in about 10% of patients with acute hepatitis B infection and 5-10% of patients with acute hepatitis C infection. This presents with a maculopapular rash and arthralgia, typically affecting the wrist, knees, elbows, and ankles. It is due to formation of immune complexes, and patients often test positive for rheumatoid …