[Hepatitis-B-surface-antibodies (detection, incidence, clinical importance)].

The AusRIA 2 test has been modified for HBs antibody detection. This technique is about 7 to 8 dilution steps more sensitive for antibody detection than the IPE. Using this modified radioimmunological technique investigations have been carried out on blood donors, patients with acute and chronic liver disease and on haemophiliacs. An HBs antibody incidence of 11% was found among voluntary blood donors. Intensive clinical investigation of blood donors positive for HBs antibodies by IPE demonstrated that the Serum GOT was elevated in 11% of cases and the liver biopsy showed histological changes of different severity in 16 out of 22 cases. Investigation of 22 cases of acute HBs antigen-positive hepatitis confirmed that nearly all the patients developed HBs antibodies within 10 weeks following the disappearance of HBs antigen. The HBs antibodies persist over years. The appearance of HBs antibodies after an acute HBs antigen-negative hepatitis can be taken as an indication of a hepatitis-B virus infection also in these cases. Among 22 HBs antigen-negative chronic hepatitis cases, HBs antibodies were detectable in 52%. Sera of 111 patients with HBs antigen-negative liver cirrhosis of varying aetiology showed HBs antibodies in 29.7% of cases. The incidence was higher in males. HBs antibodies were found in 98% of patients with haemophilia. These results reveal new aspects with regard to the importance of the hepatitis-B viurs, especially in chronic liver disease. Apart from a description of the newly-developed HBs antibody test and a discussion of the results obtained using this technique, a survey is given of the importance of HBs antibody determination by means of sensitive methods for clinical and epidemiological purposes.