Test of Cure Return Rate and Test Positivity, Strengthening the US Response to Resistant Gonorrhea, United States, 2018–2019

Abstract

Background: Reduced antibiotic susceptibility (RS) in Neisseria gonorrhoeae (GC) may increase treatment failure. Conducting tests of cure (TOC) for patients with RS-GC may facilitate identification of treatment failures. Methods:We examined 2018 to 2019 data from 8 jurisdictions participating in the US Centers for Disease Control and Prevention's Strengthening US Response to Resistant Gonorrhea project. Jurisdictions collected GC isolates and epidemiological data from patients and performed antimicrobial susceptibility testing. Minimum inhibitory concentrations of ceftriaxone, 0.125 μg/mL or greater; cefixime, 0.250 μg/mL or greater; or azithromycin, 2.0 μg/mL or greater were defined as RS. Patients with RS infections were asked to return for a TOC 8 to 10 days posttreatment. We calculated a weighted TOC return rate and described time to TOC and suspected reasons for any positive TOC results.Results: Overall, 1165 patients were diagnosed with RS infections. Over half returned for TOC (weighted TOC, 61%; 95% confidence interval, 50.1%-72.6%; range by jurisdiction, 32%-80%). Test of cure rates were higher among asymptomatic (68%) than symptomatic patients (53%, P = 0.001), and men who have sex with men (62%) compared with men who have sex with women (50%; P < 0.001). Median time between treatment and TOC was 12 days (interquartile range, 9-16). Of the 31 (4.5%) TOC patients with positive results, 13 (42%) were suspected because of reinfection and 11 (36%) because of false-positive results. There were no treatment failures suspected to be due to RS-GC.Conclusions: Most patients with a RS infection returned for a TOC, though return rates varied by jurisdiction and patient characteristics. Test of cure can identify and facilitate treatment of reinfections, but false-positive TOC results may complicate interpretation and clinical management.

New Evidence for Antimicrobial-Resistant Gonorrhea Control Programs: Lessons Learned from the SURRG Project

“…It is important to note that the average number of days from treatment to TOC was 11 day for those who tested positive versus 13 days for those who tested negative. Among those who were suspected to have tested falsely positive because of remnant nucleic acids, TOC occurred on average at 9 days 20 . These data have important implications for the new CDC gonorrhea treatment guidelines, which recommend routine TOC for all pharyngeal infections 7 to 14 days after treatment 21 .…”

“…Among those who were suspected to have tested falsely positive because of remnant nucleic acids, TOC occurred on average at 9 days. 20 These data have important implications for the new CDC gonorrhea treatment guidelines, which recommend routine TOC for all pharyngeal infections 7 to 14 days after treatment. 21 Based on Dr Schlanger and colleagues' data, TOC should be restricted to the later end of that interval, around 12 to 14 days, to decrease false-positives.…”

Strengthening the US Response to Resistant Gonorrhea: An Overview of a Multisite Program to Enhance Local Response Capacity for Antibiotic-Resistant Neisseria gonorrhoeae

“…Patients with positive TOC test results were managed per CDC treatment guidelines and local protocols. Strengthening the US Response to Resistant Gonorrhea program TOC data are presented elsewhere 19 …”

Prospective screening for sexually transmitted infections among US service members with Chlamydia trachomatis or Neisseria gonorrhoeae infection

“…This study, compared to ours and the study in Amsterdam, focused on retesting compliance versus randomizing prospectively to different timelines. In a study of 1,165 individuals having NG with reduced antimicrobial susceptibility, 61% of individuals returned for a test of cure [15]. The study reported that it did not detect any treatment failures; and moreover, that positive test events were likely due to reinfection or false positive NAAT results.…”