HTLV-III Antibodies After Immune Globulin

Abstract

To the Editor.— In their recent letter, Wolfe et al 1 presented an analysis of the potential of a transient false-positive reaction on an enzyme-linked immunosorbent assay for antibody to human T-cell lymphotropic virus type III (HTLV-III) in recipients of immune globulin (IG) made from unscreened source material. Their analysis was limited to the case of intramuscular administration of a 5-mL dose of IG to US military personnel. Two factors not included in the case analyzed by Wolfe et al can greatly increase the chance of observing a transient false-positive in the HTLV-III antibody test. The standard dose in the case presented by these authors, calculated on the basis of their assumptions, is 10 mg/kg. Intravenous (IV) IG therapy is often given at a dosage of 400 mg/kg. Consequently, a recipient of IV IG may have a serum titer of passively received antibodies that is 40 times greater than that