Uptake, yield and resource requirements of screening for asymptomatic sexually transmissible infections among HIV-positive people attending a hospital outpatient clinic

Background We performed a prospective audit of screening for asymptomatic sexually transmissible infections (STIs), during an intensive effort to screen all patients at our hospital-based HIV clinic. We aimed to measure the effectiveness and resource implications of our screening program. Methods: All outpatients who attended during an 8-month period were invited to take part in opt-out screening for chlamydia (Chlamydia trachomatis), gonorrhoea (Neisseria gonorrhoeae) and syphilis. Participants completed a brief questionnaire, were asked about current symptoms of STIs and self-collected specimens for laboratory testing. Results: The majority (535 out of 673, 80%) of the patients who were asked to participate provided specimens for screening. No chlamydia, gonorrhoea or syphilis infections were identified in women (n = 91) or in heterosexual men (n = 76). In contrast, 34 out of 368 (10%) of men who have sex with men tested positive (chlamydia, 25; gonorrhoea, 2; chlamydia and gonorrhoea, 2; syphilis, 5). The laboratory cost of diagnosing each case of rectal chlamydia or gonorrhoea (NZ$664) was substantially lower than the cost of diagnosing each case of urethral infection (NZ$5309). Conclusions: There was high uptake of screening among our clinic population, who preferred screening to be performed at the hospital clinic. The yield of screening men who have sex with men warrants continued annual screening for rectal gonorrhoea and chlamydia and for syphilis.