Rapid Increase in Gonorrhea Cases With Reduced Susceptibility to Azithromycin in Columbus, Ohio.

Abstract

Body of Letter: National data show an increasing trend of reduced azithromycin susceptibility (AZM-RS) among Neisseria gonorrhoeae (Ng) isolates, especially in the Midwest.1 Sentinel surveillance data from the Gonococcal Isolate Surveillance Project, which examines isolates from men with urethritis from 27 sites across the United States, indicates that the proportion of AZM-RS Ng isolates (minimum inhibitory concentration [MIC] ≥2 μg/mL) increased 4-fold between 2013 (0.6%) and 2014 (2.5%).1 Most AZM-RS Ng infections occur in men who have sex with men.1,2 The Columbus Public Health STD clinic in Columbus, Ohio, has participated in the Gonococcal Isolate Surveillance Project since 2012. We detected zero cases of AZM-RS Ng in 2015 and 5 cases in 2016 (April, June, July, August, and December). However, we identified 30 cases between January and July 2017; 25 isolates had an AZM MIC of 2 μg/mL and 5 had an MIC of 8 μg/mL. To improve local detection of AZM-RS Ng, we compared characteristics of men with AZM-susceptible Ng urethritis (n = 224) and those with AZM-RS Ng urethritis (n = 30) detected between January and July 2017 (Table 1). Most men with AZM-RS Ng urethritis were identified in the months of June (n = 8) and July 2017 (n = 10), suggesting an accelerating trend. Compared with men with AZM-susceptible Ng urethritis, men with AZM-RS Ng urethritis were more likely to be white (P = 0.02), to report intravenous drug use in the previous year (P = 0.008), and to be HIV-positive (P = 0.04). Although more than half (53%) of men with AZM-RS Ng were heterosexual, the proportion identifying as homosexual (47%) was much higher than the proportion of AZM-susceptible men identifying as homosexual (17%; P = 0.003). We observed no significant differences by age, lifetime or recent Ng history, symptoms, recent international travel, recent sex work exposure, recent non–injection drug use, or recent antibiotic use. Although there was one Ng isolate with an increased MIC value to cefixime (MIC, 0.250 μg/mL) and one to both cefixime (MIC, 0.250 μg/mL) and ceftriaxone (MIC, 0.125 μg/mL), neither of these had concomitant reduced susceptibility to AZM. Ninety-seven percent (n = 29) of men with AZM-RS Ng urethritis received single-dose ceftriaxone (250 mg) plus AZM (1 g), and 3% (n = 1) received single-dose ceftriaxone (250 mg) plus 7 days of doxycycline (100 mg twice per day).TABLE 1: Characteristics of Men With Ng Urethritis, Comparing Those With Azithromycin-Susceptible Ng (n = 224) to Those With Reduced Azithromycin-Susceptibility (n = 30), January to July 2017We report a rapid and alarming increase in cases of AZM-RS Ng urethritis in 2017 in Columbus, Ohio (12% of Ng isolates examined). In contrast to recent reports from King County, WA,2 more than half of our AZM-RS Ng infections occurred in heterosexual patients. The Centers for Disease Control and Prevention recommends dual therapy (ceftriaxone plus AZM) to treat Ng3; the importance of this approach is confirmed by our data, because none of our AZM-RS Ng isolates showed increased MICs to ceftriaxone. However, a genetically linked cluster of 8 Ng isolates with high-level AZM resistance by agar dilution (MIC, >16 μg/mL) was reported in Hawaii. Five of these isolates had simultaneous increased MICs to ceftriaxone (MIC, 0.125 μg/mL),4 further heightening public health concerns about the lack of alternative effective antibiotic options for the treatment of Ng. Expanded surveillance, rapid resistance testing, and new antibiotics are urgently needed in the face of rising Ng antibiotic resistance. Jose A. Bazan, DO Sexual Health Clinic Columbus Public Health Columbus, OH Division of Infectious Diseases The Ohio State University College of Medicine Columbus, OHMysheika Williams Roberts, MD, MPH Sexual Health Clinic Columbus Public Health Columbus, OHOlusegun O. Soge, PhD Neisseria Reference Laboratory Harborview Medical Center University of Washington Seattle, WAElizabeth A. Torrone, PhD, MSPH Division of STD Prevention Centers for Disease Control and Prevention Atlanta, GAAmanda Dennison, MPH Ohio Department of Health Columbus, OHMelissa Ervin, MT, (ASCP) Sexual Health Clinic Columbus Public Health Columbus, OHSopheay Hun, MBA, MLS, (ASCP) Antimicrobial Resistance Regional Laboratory Washington State Department of Health Public Health Laboratories Shoreline, WAKaren S. Fields, MS, BSN, RN Sexual Health Clinic Columbus Public Health Columbus, OHAbigail N. Turner, PhD Division of Infectious Diseases The Ohio State University College of Medicine Columbus, OH