O7.3 - The impact of near-to-patient testing of sexually transmitted infections on clinical practice and antimicrobial stewardship: the NEPTUNE study

Background: Presumptive treatment in STI syndromes and among sexual contacts of an STI leads to antibiotic overuse and misuse. We aimed to determine if near-to-patient-testing for Neisseria gonorroheae, Chlamydia trachomatis and Mycoplasma genitalium (plus macrolide-resistance-mutations) would improve appropriate prescribing and reduce antibiotic overuse in patients with non-gonococcal urethritis (NGU), suspected proctitis or pelvic inflammatory disease (PID), patients attending as STI-contacts, and patients attending for M.genitalium test-of-cure (MG-TOC). Timely STI-specific partner-notification was measured.

Methods: From March-December 2021, enrolled patients underwent testing for STIs by molecular near-to-patient-testing (SpeeDx; GeneXpert® System,Cepheid, Sunnyvale, CA, USA) and transcription-mediated-amplification standard-of-care testing (Aptima, Hologic). We calculated the proportion with an STI detected among those who presented with an STI syndrome, as an STI-contact, or for MG-TOC. To estimate the benefit of near-to-patient-testing on antimicrobial stewardship among those normally receiving syndromic therapy, we compared prescribing practices among patients undergoing near-to-patient-testing with a control group undergoing standard-of-care. Finally, patients received an SMS asking how many partners they had notified of the specific STI within 24h.

Results: Among 870 patients (representing 975 consults) undergoing near-to-patient-testing, an STI was detected in 63/252 (25.0%) with NGU (12.3% C.trachomatis; 11.3% M.genitalium; 2.8% N.gonorrhoeae), 18/51 (35.3%) with proctitis (21.6% N.gonorrhoeae; 9.8% C.trachomatis; 11.8% M.genitalium) and 5/51 (9.8%) with pelvic pain (5.8% M.genitalium; 2.0% C.trachomatis; 2.0% N.gonorrhoeae). Near-to-patient-testing detected an STI among 183/527 (34.7%) STI-contacts, and M.genitalium among 35/161 (21.7%) MG-TOC presentations. Among patients with an STI syndrome, significantly more patients undergoing near-to-patient-testing vs standard-of care received etiologic therapy (72.6% vs 8.8%, respectively). This resulted in more patients undergoing near-to-patient-testing vs standard-of-care receiving precise treatment (correct drug/no drug appropriately; 80.5% vs 21.2%, respectively), and fewer patients undergoing near-to-patient-testing being mistreated (incorrect drug/no pathogen detected; 17.2% vs 66.0%, respectively). 173/276 with an STI detected reported partner-notification via reply-SMS; 95.4% notified all or some sexual partners and 85.9% of these notifications occurred < 24h post-result.

Conclusion: The three bacterial STIs were detected in less than a third of patients, highlighting the need for timely etiologic strategies to mitigate antibiotic overuse and misuse as a result of presumptive therapy. Near-to-patient-testing resulted in improved antimicrobial stewardship, and rapid and high rates of STI-specific partner-notification.