SPONTANEOUS HEPATITIS-B SURFACE-ANTIGEN CLEARANCE IN A LONG-TERM FOLLOW-UP-STUDY OF PATIENTS WITH CHRONIC TYPE-B HEPATITIS - LACK OF CORRELATION WITH HEPATITIS-C AND HEPATITIS-D VIRUS SUPERINFECTION

We investigated the frequency of HBsAg clearance and the possible role of viral superinfection in a long-term follow-up of 184 patients with chronic hepatitis B (CHB). Our subjects were 184 patients with chroni c hepatitis B and the follow-up was 12-216 months (mean 66.2 +/- 53.7 months). The investigative methods used were: immunoenzymatic assays f or HBV, HCV, HDV, and HIV markers; polymerase chain reaction (PCR) for HBV DNA; and liver biopsy and immunoperoxidase. During the follow-up, 20 of the 184 patients cleared serum HBsAg. A comparison of patients with persistent HBsAg (group I) and of those who cleat-ed this marker (group TI) showed a significant difference in mortality (P = 0.002) be tween the two groups and a tendency to a more severe exacerbation (fla re) in group II (P = 0.07). Antibodies to hepatitis C and D virus as w ell as antibodies to HIV were equally distributed in both groups. Thir teen patients (7.9%) from group I, but none from group II, subsequentl y developed hepatocellular carcinoma. These results suggest that the f requency of spontaneous clearance of HBsAg during chronic HBV infectio n is low. No determinant factor for the clearance was found, including the presence of liver cirrhosis. Serum HBV DNA was undetectable by PC R after clearance in 16 out of 17 patients.