Screening for genital and anorectal sexually transmitted infections in HIV prevention trials in Africa

Marianne Louise Grijsen ¹, Susan M Graham ², Mary Mwangome ³, Peter Githua ³, Sarah Mutimba ³, Lorraine Wamuyu ³, Haile S Okuku ³, Matthew A Price ⁴, Scott R McClelland ², Adrian D Smith ⁵ and Eduard J Sanders ^3*

¹ Kenya Medical Research Institute, Netherlands
² University of Washington, United States
³ Kenya Medical Research Institute, Kenya
⁴ International AIDS Vaccine Initiative, United States
⁵ University of Oxford, United Kingdom

^* To whom correspondence should be addressed. E-mail: esanders{at}kilifi.kemri-wellcome.org.

Accepted 7 March 2008

Abstract

Objectives: Our objectives were (1) to demonstrate the value of routine, basic sexually transmitted infection (STI) screening at enrolment into an HIV-1 vaccine feasibility cohort study; and (2) to highlight the importance of soliciting a history of receptive anal intercourse (RAI) in adults identified as ¡¥high risk¡¦.

Methods: Routine STI screening was offered to adults at high risk for HIV-1 upon enrolment into a cohort study in preparation for HIV-1 vaccine trials. Risk behaviors and STI prevalence were summarized, and the value of microscopy assessed. Associations between prevalent HIV-1 infection and RAI or prevalent STIs were evaluated with multiple logistic regression.

Results: Participants had a high burden of untreated STIs. Symptom-directed management would have missed 67% of urethritis cases in men and 59% of cervicitis cases in women. RAI was reported by 36% of male and 18% of female participants. RAI was strongly associated with HIV-1 in men (adjusted odds ratio [aOR] = 3.8, 95% CI 2.0-V 6.9), and independently associated with syphilis in women (aOR 12.9, 95% CI 3.4-V 48.7).

Conclusions: High-risk adults recruited for HIV-1 prevention trials carry a high STI burden. Symptom-directed treatment may miss many cases, and simple laboratory-based screening can be done with little cost. Risk assessment should include questions about anal intercourse and whether condoms were used. STI screening, including specific assessment for anorectal disease, should be offered in African research settings recruiting participants at high risk for HIV-1 acquisition.