Comparison of techniques for HIV-1 RNA detection and quantitation in cervicovaginal secretions

Principles: HIV-1 in female genital secretions has been measured using swab s, Sno Strips (Akorn, Inc., Buffalo Grove, IL), and cervicovaginal lavage ( CVL), but little is known regarding the comparability of these collection t echniques. Methods: We compared HIV-1 RNA detection and quantity in specimens obtained from HIV-l-seropositive women in Kenya using three sample collection techn iques and three storage techniques and evaluated reproducibility in samples collected 5 days apart. Specimens were stored in no medium, freezing mediu m, or TRI Reagent (Molecular Research Center, Cincinnati, OH) for 2 to 15 m onths. Results: HIV-1 RNA assays were conducted on 640 specimens from 20 antiretro viral naive women. Storage in TRI Reagent significantly enhanced detection of genital HIV-1 and yielded significantly higher mean log(10) RNA levels t han specimens collected in either no or freezing medium. The prevalence of HIV-1 RNA detection in TRI Reagent ranged from 50% to 80% depending on coll ection method and was highest in cervical swabs. Mean log(10) HIV-1 RNA lev els were 3.1 log(10) copies/cervical swab, 2.6 log(10) copies/cervical Sno Strip, 2.5 log(10) copies/vaginal swab, 2.4 log(10) copies/ vaginal Sno Str ip, 2.9 log(10) copies/ml for cervicovaginal lavage (CVL) cell pellet, and 2.4 log(10) copies/ml in CVL supernatant. Comparing specimens from days 1 a nd 6, there was significant concordance of HIV-1 RNA detection and correlat ion of HIV-1 RNA levels for cervical swabs, vaginal swabs, vaginal Sno Stri ps, and CVL cell pellets (kappa, 0.5-0.9; r, 0.5-0.9), but not for cervical Sno Strips or CVL supernatants. Conclusions: Cervical or vaginal swab, vaginal Sno Strip, and CVL collectio n led to reproducible measurement of genital HIV-1 RNA, despite storage for several months and international transport. Collection using swabs was sim pler than Sno Strips or cervicovaginal lavage, and yielded the highest prev alence of HIV-1 RNA detection and reproducibility.