Screening cornea donors for antibodies against human immunodeficiency virus. Efficacy of ELISA testing of cadaveric sera and aqueous humor

Abstract

Coded cadaveric sera from 35 patients with acquired immunodeficiency syndrome (AIDS), from 45 cadavers at high risk of human immunodeficiency virus (HIV) infection, and from 262 cadavers without known signs or risk of AIDS were assessed using three commercially available enzyme-linked immunosorbent assays (ELISA) kits and Western blot analysis. Greater than 94% sensitivity and 99% specificity was achieved with each of the ELISA test kits using cadaveric sera. The Western blot method gave 97.1% sensitivity compared with the autopsy-proven diagnosis of AIDS. Positive results were obtained on sera from AIDS cadavers even if the time of blood draw was delayed 35 hours from death and the time of sera preparation was delayed up to 176 days. False-negative or false-positive ELISA results did not appear to correlate with hemolysis or any parameter of sera preparation. In contrast to the high sensitivity in testing sera, only 16 to 26% of aqueous humor samples from AIDS cadavers were ELISA-positive and 79% were positive by Western blot. These results indicate that three commercially available ELISA test kits are an effective means of screening cadaveric sera for antibodies to HIV, but that aqueous humor cannot be reliably substituted for cadaveric sera to screen potential cornea donors by an ELISA assay.