Positive direct antiglobulin tests with antilymphocyte globulin.

Abstract

Patients receiving antilymphocyte globulin (ALG) of equine origin, for prophylactic immunosuppression following renal transplantation or for rejection episodes, develop a positive direct antiglobulin test (DAT), mainly of the IgG type. This finding may be observed as early as the first day following the administration of ALG. The cause for the positive DAT is due to the presence of antihorse globulin in the reagent antiglobulin serum reacting with ALG antigenic material coating the patients' red blood cells. The serum of some of these patients also may result in incompatible cross-matches. These serums and all of the eluates react with donor and reagent red blood cells demonstrating no particular blood group specificity.