Non-B hepatitis in Japanese recipients of blood transfusions: clinical and serologic studies after the introduction of laboratory screening of donor blood for hepatitis B surface antigen.

Cases of hepatitis virus infection in Japanese recipients of blood transfusions were serologically and clinically analyzed after the introduction of laboratory screening of donor blood for hepatitis B surface antigen by counter immunoelectrophoresis. Non-A, non-B hepatitis occurred in 116 (10.7%) and hepatitis type B in nine (0.9%) of the 1,082 recipients. The incubation period of the post-transfusion non-A, non-B hepatitis cases varied from two to 33 weeks, but most occurred within 15 weeks. In 97 (83.6%) of the 116 cases of non-A, non-B hepatitis studied, the duration of abnormal elevation of the level of serum alanine aminotransferase (glutamic-pyruvic transaminase [SGPT]) was 16 weeks. The cases of non-A, non-B hepatitis could be divided into three groups according to the pattern of elevation of SGPT levels. These findings may suggest either a multiple etiology for non-A, non-B hepatitis or a variety of clinical symptoms with a single etiology for the infection.