A clinical and laboratory evaluation of immune serum globulin from donors with a history of hepatitis: attempted prevention of post-transfusion hepatitis.

A controlled trial of passive immunization for prevention of post-transfusion viral hepatitis was carried out in order to determine whether effective levels of antibody were present in the "convalescent" immune serum globulin used in the study. This globulin was prepared selectively from plasma of donors giving a history of overt viral hepatitis two or more years earlier. The proportion of contributors to the globulin who had B hepatitis was unknown but the final product contained a low titer of antibody to the surface antigen of hepatitis B virus (anti-HBs). The failure of 20 ml of immune serum globulin to reduce the incidence of type B post-transfusion hepatitis (7/93) below that of placebo-treated controls (8/102) was not unexpected in view of the globulin's low titer of anti-HBs. However, more than two thirds of the post-transfusion cases were not type B and were as plentiful among globulin recipients (17/93) as among controls (17/102). Although some of the donors from whom the immune serum globulin was obtained may once have had the same type(s) of hepatitis as the non-B cases currently observed in transfusion recipients, the globulin apparently did not contain enough specific antibody to confer protection in the dose schedule tested.