LB11 Treatment Failures with Cephalosporin Monotherapy Vs Dual Therapy for Gonorrhea at Two Alberta STI Clinics, 2010-2013

Tuesday, June 10, 2014
Exhibit Hall
Jennifer Gratrix, RN, MSc, STI Services, Alberta Health Services, Edmonton, AB, Canada, Joshua Bergman, RN, MPH, Alberta Health Services-Edmonton STI Clinic, Edmonton, AB, Canada, Ron Read, MD, PhD, FRCPC, Alberta Health Services-Calgary STI Clinic, Calgary, AB, Canada, Tom Wong, MD, MPH, FRCPC, Professional Guidelines and Public Health Practice Division, Centre for Communicable Diseases and Infection Control, Public Health Agency of Canada, Ottawa, ON, Canada and Ameeta Singh, BMBS, MSc, FRCPC, Division of Infectious Diseases, University of Alberta, Edmonton, AB, Canada

Background: The emergence of decreasing N. gonorrhoeae (NG) susceptibility to the “last-line” cephalosporins and azithromycin is a public health threat. We sought to examine the effectiveness of different recommended treatment regimens for different anatomical sites, different patient populations and different MICs.

Methods: Culture positive NG cases, who returned for test of cure (TOC) within 30 days of treatment to two Alberta STI Clinics between January 1, 2010 and September 30, 2013, were reviewed. Treatment failures (TF) were defined as the absence of reported sexual contact during the post-treatment period and a positive culture ≥72 hours post-treatment or a positive NAAT ≥2 weeks post-treatment. 

Results: A total of 1,085 isolates were reviewed. Nearly two-thirds (62.9%) of isolates were collected among men having sex with men (MSM), 1.2% were among pregnant women, and 35.9% were among non-MSM and non-pregnant women. The site of isolate collection was evenly distributed between oropharyngeal (34.7%), anorectal (31.6%), and urogenital (33.6%). Follow-up TOC assessment rates at 30 days post-treatment were highest for extragenital sites (oropharyngeal: 40.1% and anorectal: 35.0% vs. urogenital 8.2%; P=<0.001), although no significant difference was found by patient group. Fourteen TF involving cefixime 400 mg monotherapy were found, 11 among MSM and 2 among non-MSM and non-pregnant. An additional TF was found in a pregnant female using cefixime 800 mg monotherapy. All TF isolates were fully susceptible to cefixime, ceftriaxone and azithromycin. Nearly one-quarter (23.9%; 11/46) of the MSM patient group treated with cefixime 400 mg monotherapy who returned for a TOC failed treatment. TF by site ranged from 13% (3/23) rectally, 25% (1/4) urogenitally, and 36.8% (7/19) from the oropharynx. 

Conclusions: In contrast to cefixime monotherapy, no TF were identified with combination NG treatment.  Our data support the 2011 Canadian STI Guidelines switch to combination treatment of NG with a cephalosporin plus azithromycin.