Poor correlation between reactive syphilis serology and human immunodeficiency virus testing among potential cornea...

The current practice in which eye banks screen cornea donors for syphilis is based mainly on the potential utility of positive syphilis serology as a surrogate marker for human immunodeficiency virus-1 (HIV-1) infection. We examined the correlation between positive syphilis and HIV-1 serologies within the potential cornea donor population.

We distributed a questionnaire to 94 eye banks in the United States regarding their rates of positive serology for syphilis and HIV-1 between Feb. 1 and July 30, 1992. We subsequently used the polymerase chain reaction for HIV-1 to further evaluate the whole blood of 21 rapid plasma reagin and fluorescent treponemal antibody-positive, HIV-1 enzyme-linked immunosorbent assay (ELISA)-negative cornea donors to determine whether these donors were infected with HIV-1 but were within a seronegative window for HIV-1 antibodies at their time of death.

Of 8,932 donors screened, 103 (1.15%) had reactive screening for syphilis serology and 35 (0.39%) were HIV-1 seropositive. No donor with positive syphilis serology was also HIV-1 seropositive. Twelve of 31 donors who originally tested seropositive for syphilis by nontreponemal screening tests (Venereal Disease Research Laboratory or rapid plasma reagin tests) proved seronegative for syphilis when further tested with a treponemal test (FTA-ABS or microhemagglutination-Treponema pallidum), suggesting a high (38.7%) false-positive rate for the syphilis screening tests. Additionally, all 21 rapid plasma reagin and fluorescent-treponemal antibody-positive, HIV-1 ELISA-negative donors further tested were also negative for HIV-1 by the polymerase chain reaction.

Among potential cornea donors, a population prescreened for identifiable HIV-1 risk factors, positive syphilis serology appears to be a poor marker for HIV-1 infection. The role of syphilis screening of potential cornea donors may need to be reevaluated.