Pharyngeal Gonorrhea and Chlamydial Infections in Men who have Sex with Men, a Hidden Threat to the HIV Epidemic

Background: Pharyngeal infections with gonorrhea (GC) and chlamydia (CT) can be missed if screened only by routine methods of urethral or urine specimens and may increase the risk of sexually transmitted infections and HIV acquisition and transmission. The prevalence of pharyngeal GC and CT in men who have sex with men (MSM) has been reported as 5.3-9.2% and 1.4-1.9% respectively. The objective of this study is to determine the rates of pharyngeal GC and CT infections in MSM in the Miami Dade Health Department (MDHD) STD clinic. Methods: Routine screening for pharyngeal GC and CT infections in MSM was implemented in the MDHD STD clinic in October 2011 using APTIMA Combo 2 Assay®. Validation studies were performed in the Florida Department of Health Laboratories prior to implementation of the test. Retrospective review of medical records of individuals tested for pharyngeal GC/CT from October 2011 to March 2012 was performed. Results from urine and rectal GC/CT testing done at the same time from the same individuals were also reviewed. Results: A total of 475 pharyngeal swabs were performed. Fifty-two (10.9%) were positive for GC and 13 (2.7%) were positive for CT. Among the individuals with GC pharyngeal infection, 21 (52.5%) had a positive GC rectal test and 14 (28%) a positive urine test. Among the individuals with CT pharyngeal infection, 3 (30%) had a positive CT rectal test and 1 (7.7%) a positive urine test. Conclusions: The prevalence of pharyngeal GC/CT in MSM in the MDHD STD clinic is higher than what has been previously reported in other centers. The discrepancy between pharyngeal, rectal, and urine tests emphasizes the importance of extragenital testing in the MSM population.