Positive direct antiglobulin test associated with hyperglobulinemia in acquired immunodeficiency syndrome (AIDS).

This study determined the prevalence and clinical significance of a positive direct antiglobulin test (DAT) observed in pretransfusion tests on red cells from patients with acquired immunodeficiency syndrome (AIDS). Transfusion service records showed that prevalence of a positive DAT on red cells was 18% (10/55) in AIDS patients compared to 0.6% in general hospital patients during a 2-year period (1981-1983). A similar rate of 18% (8/45) was observed in other hyperglobulinemic patients. Of the 10 AIDS patients whose red cells were DAT positive, four had IgG and complement, four had IgG, and two had complement alone on their red cells. The eluates were not reactive with normal red cells nor with penicillin or cephalothin-coated red cells. Clinically, no hemolysis was observed. In this series a positive DAT in AIDS patients appeared not to be associated with autoimmune hemolytic anemia. The positive DAT in AIDS patients may be due to the hyperglobulinemic state.