Asymptomatic urethritis and detection of HIV-1 RNA in seminal plasma

Objective: To define risk factors for detection of HIV-1 RNA in semen in me n attending the two largest HIV clinics in the West Midlands. Methods: 94 HIV-1 seropositive men at any stage of infection donated matche d semen and blood samples. 36 subjects (38%) were on no antiretroviral trea tment, 12 (13%) were on dual therapy, and 46 (49%) were on three or more dr ugs. Median CD4 count was 291 cells x 10(6)/l. 87 subjects underwent a uret hritis screen (Gram stained urethral smear and culture for gonococcus, and LCR for Chlamydia trachomatis on first pass urine). Quantitative cell free HIV-1 RNA was determined by commercial nucleic acid sequence based assay wi th a lower detection limit of 800 copies/ml for semen and 400 copies/ml for blood. Independent risk factors for seminal HIV RNA detection were defined by logistic regression. Results: In univariate analysis, subjects not taking antiretrovirals were 1 1 times more likely to shed HIV RNA (21/36 (58%) v 6/58 (10%); p<0.0001). S even subjects (8%) had urethritis (including one C trachomatis infection). Urethritis was significantly associated with detection of seminal HIV RNA ( adjusted OR, 80.2; p=0.006), as was blood plasma viral load (adj OR, 19.3 p er factor 10 increase; p<0.001) and age (adj OR, 1.16 per 1 year older; p=0 .001). Antiviral treatment status, absolute CD4 and CD8 count, clinical sta ge, treatment centre, ethnicity, and risk factor were not independent predi ctors. No subject with undetectable blood viral load had detectable seminal HIV RNA. Conclusion: Asymptomatic urethritis is independently associated with semina l HIV RNA shedding.