EDITOR, - Carol A Seymour's editorial1 and the papers on hepatitis C in the same issue illustrate the problems of defining chronic hepatitis C and of identifying patients who would benefit from regular follow up in a gastroenterology clinic. We and colleagues have found that only liver biopsy reliably identifies patients with chronic infection. Kate E Ryan and colleagues rightly question the effectiveness of counselling when so little is known of the natural course of this infection.2

Liver biopsy is not a minor procedure, and scarce and expensive medical resources should be used only when the patient will benefit. The patient must be given an accurate prognosis and treatment with interferon alfa and other antivirals should be offered when appropriate, although the long term effects of such intervention on the prognosis of liver disease associated with hepatitis C are unknown.

Much of this information is not new. It has been known since the 1970s that a normal serum alanine aminotransferase activity in repeated samples taken over an extended period does not exclude the finding of non-A, non-B hepatitis on liver biopsy.^3,4 Published studies of liver biopsies in blood donors positive for antibodies to hepatitis C virus show varying proportions with normal histological appearances and …