The relationship of HIV-1 viral sequences detected by the polymerase chain reaction in haemophilic patients to clinical and other markers of infection.

A nested primer polymerase chain reaction (PCR) of pol gene sequences of human immunodeficiency virus-1 (HIV-1) was applied to whole blood of 31 haemophiliacs who were, or had been, positive for HIV p24 antibody (HIVAb) by enzyme linked immunosorbent assay (ELISA) and samples from 22 persistently HIVAb negative haemophiliacs who had been at risk of contracting HIV from treatment. The results were compared with those of p24 HIV antigen determination, T4 cell counts beta 2 Microglobulin (beta 2M) levels and clinical evidence of progression of HIV disease. There was no discrepancy between the PCR results and past or present seropositivity for HIVAb. The qualitative PCR was more sensitive than the p24 antigen assay but the presence of the latter was predictive of progression of infection as determined clinically and by falling T4 cell counts and rising levels of beta 2M. The results of the PCR are reassuring for HIVAb negative haemophiliacs at risk from treatment and to HIVAb negative sexual contacts of HIVAb positive persons.