Detection of human immunodeficiency virus-1 RNA and DNA by extractive and in situ PCR in unprocessed semen and seminal fractions isolated by semen washing procedure

Background: To determine the presence of human immunodeficiency virus-1(HIV-1)viral RNA/DNA in whole semen, in properly isolated seminal fractions and in spermatozoa after swim-up, by extractive nested PCR and to compare the detection of HIV DNA by in situ PCR (IS-PCR)with the result of nested PCR. Methods: we tested HIV-1 RNA and DNA by nested PCR in semen and in seminal fractions from 55 patients. Non-spermatic cells and spermtozoa pellet fractions from 10 HIV-1 positive and five HIV-1 negative men were tested for proviral DNA by IS-PCR. Results: All samples of spermatozoa recovered after sperm washing were free of HIV RNA. HIV RNA tested positive in seven (13%)seminal plasma samples and only in two (4,2%)whole semen of these same samples. Of the seven seminal plasma samples testing positive for HIV RNA, four men had elevated blood viral load and three an undetectable viraemia. HIV DNA by IS-PCR turned positive in three of five samples in semen of HIV-noninfected men. Conclusions: HIV RNA/DNA detection in the semen of HIV-infected men proves the efficacy of sperm washing with swim-up of spermatozoa. It is recommended that nested PCR be conducted on purified seminal compartments. IS-PCR is inadequate for detecting HIV in semen.