Clinical course and prognosis of acute hepatitis.

The clinical course of acute viral hepatitis may vary from asymptomatic to fulminant, and the final outcome can be complete recovery, chronic hepatitis or cirrhosis. The two main challenges this generally benign, self limiting infection has presented for may years have been to understand 1) the progression to fulminant hepatitis, and 2) the progression to chronic hepatitis or cirrhosis. Fulminant hepatitis may appear infrequently (1-2 % of patients with clinical hepatitis) in both type A and type B infections. Nearly 10% of patients with acute viral hepatitis type B develop either chronic hepatitis or cirrhosis. The exact figures for progression to chronicity in patients with type A infections are probably less,but are still not fully known. During the acute phase of the disease, the patients with later progression to chronicity differ significantly from those with subsequent resolution in a number of serological, biochemical and morphological variables. Persistence of HBS antigenaemia for more than 13 weeks, a high concentration of circulating Dane particles, and the presence in the serum of the "e" antigenic determinant seem to be reliable prognostic markers for pregression to chronic hepatitis or cirrhosis. Such markers are prerequisites for therapeutic trials with potent drugs which are only justified for patients with fulminant hepatitis and patients with progression to chronicity. If the different outcome of viral hepatitis is a result of the individual T-cell function, these two categories of patients may represent the opposite extremes in lymphocytic function. Controlled clinical trials are required to evaluate the clinical effect of immunosuppression in fulminant hepatitis and immunostimulation in chronic hepatitis.