Near-to-patient-testing to inform targeted antibiotic use for sexually transmitted infections in a public sexual health clinic: the NEPTUNE cohort study

Abstract

BackgroundEmpiric treatment of sexually transmitted infections can cause unnecessary antibiotic use. We determined if near-to-patient-testing (NPT) for Neisseria gonorrhoeae, Chlamydia trachomatis and Mycoplasma genitalium (MG) improved antibiotic-use for a range of clinical presentations. MethodsClients attending with non-gonococcal-urethritis (NGU), proctitis, as STI-contacts, or for an MG-test-of-cure (MG-TOC) between March-December 2021 were recruited. Participants received near-to-patient-testing (NPT-group) for the three STIs using the GeneXpert® System (Cepheid), and concurrent routine-testing by transcription-mediated-amplification (TMA; Aptima, Hologic). Antibiotic-use among NGU or proctitis cases in the NPT-group was compared to clinic-controls undergoing routine-testing only. The proportion in the NPT-group who notified partners <24hrs of their STI-specific result was calculated. FindingsAmong 904 consults by 808 NPT-participants, ≥1 STI was detected in 63/252 (25·0%) with NGU, 18/51 (35·3%) with proctitis, and 167/527 (31·7%) STI-contacts. MG was detected among 35/161 (21·7%) MG-TOC consults. Among NGU and proctitis cases, fewer in the NPT-group received empiric treatment compared to clinic-controls (29·4% [95%CI:24·3-34·9%] vs 83·8% [95%CI:79·2-87·8%], p<0·001), resulting in more NPT-group cases appropriately treated (STI-specific drug/no drug appropriately; 80·9% [95%CI:76·0-85·1%] vs 33·0% [95%CI:27·7-38·6%], p<0·001) and fewer mistreated (incorrect drug/treated but pathogen-negative; 17·8% [13·7-22·6%] vs 54·9% [40·3-68·9%], p<0·001). Of 173/276 in the NPT-group with an STI who responded regarding partner-notification, 95·4% notified all/some partners; 85·9% notified them <24hrs of the STI-specific result. InterpretationNear-to-patient-testing significantly improved antibiotic use and a high proportion of individuals rapidly notified partners of STI-specific results, highlighting the broad benefits of timely diagnostic strategies for STIs in clinical decision making and partner notification. FundingARC ITRP Hub-grant; NHMRC