Concomitant hepatitis B surface antigen and antibody in thirteen patients.

Both hepatitis B surface antigen (HBsAg) and its antibody (anti-HBs) were found in 13 patients. Nine patients had HBsAg subtype ad, and 7 had anti-HBs monotypic subtype anti-y. Nine patients had HBsAg before detectable levels of anti-HBs were present. Of the 6 patients whose serum contained subtypes of both HBsAg and anti-HBs, 4 had HBsAg before development of the monotypic antibody. All patients have remained positive for HBsAg and anti-HBs (mean duration, 55.5 weeks). Nine patients were positive for HBeAg, and 7 had renal disease. Six of these seven patients are on hemodialysis. Because of the differing subtype specificities of the circulating HBsAg and anti-HBs, we conclude that HBsAg and anti-HBs occur concomitantly. The presence of HBeAg, which indicates infectivity, is common in our study group, suggesting that these patients are a reservoir for transmission of hepatitis-B-virus infection. Therefore, the presence of anti-HBs alone does not indicate a noninfectious serum. Concomitant HBsAg and anti-HBs seems to be particularly common in patients with renal disease who are on hemodialysis.