The aim of this study was to determine if knowledge of both the serum HCV RNA and serum anti core IgM antibody status enabled one to predict the histological severity in chronic hepatitis C. We studied 45 female patients with chronic hepatitis C infection. The presence or absence of IgM antibodies to HCV and HCV RNA by PCR in each patient's serum was determined. Liver biopsies performed were scored according to a modified Desmet's histological activity index. Negative HCV RNA patients had least histological change. HCV RNA positive patients who were also IgM antibody positive had lower scores than their IgM negative counterparts. The grade of histological severity is more accurately predictable from knowledge of both the HCV RNA and IgM anti HCV status of the patient.