SUPERINFECTION WITH HEPATITIS-C VIRUS IN HEMODIALYSIS-PATIENTS WITH HEPATITIS-B SURFACE ANTIGENEMIA - ITS PREVALENCE AND CLINICAL-SIGNIFICANCE IN TAIWAN

A survey of hepatitis B surface antigen (HBsAg) and antibodies against hepatitis C virus (anti-HCV) in 173 patients undergoing hemodialysis in Taiwan revealed that 15 (9%) patients were positive for both HBsAg and anti-HCV. 106 (61%) were positive for anti-HCV alone, and 14(8%) w ere positive for HBsAg alone. Most HBsAg positivity was acquired befor e the onset of hemodialysis. Anti-HCV positivity, however, was mainly acquired via the hemodialysis procedure. Patients with dual markers we re younger (43.7 +/- 3.3 years old, p = 0.0274), had the longest perio d on hemodialysis (6.6 +/- 1.3 years, p < 0.001), and more severe live r dysfunction. When compared with those who were negative for both mar kers, patients with both HBsAg and anti-HCV had an increased incidence of chronicity (5/15 vs, 2/38; p < 0.05), ultrasonographic cirrhosis ( 5/15 vs. 1/38; p < 0.05), and clinical decompensation (2/15 vs. 0/38: p < 0.05). Their risk for developing ultrasonographic cirrhosis and cl inical decompensation was also greater than that of patients with anti -HCV alone (5/15 vs. 8/106 and 2/15 vs. 2/106; p < 0.05 for both). The presence of HBsAg alone, however, did not increase the incidence of l iver dysfunction. The presence of anti-HCV alone was only associated w ith a greater elevation of serum alanine aminotransferase (44.2 +/- 5. 5 vs. 19.1 +/- 2.5 U/l; p < 0.05) and an increased incidence of chroni city (30/106 vs. 2/38; p < 0.05). Our results indicate that a high pre valence of HCV superinfection impose a significant risk on a large pop ulation of HBsAg-positive hemodialysis patients in Taiwan. As the coex istence of anti-HCV and HBsAg is associated with more severe liver dys function, it is urgent to devise effective methods to prevent HCV circ ulation in a hemodialysis environment - especially in a hepatitis B vi rus endemic area such as Taiwan.