Prevalence of Rectal Chlamydia and Gonorrhea Before and After Implementation of Routine Rectal Screening

Background:
The Centers for Disease Control and Prevention (CDC) recommends rectal chlamydia (CT) and gonorrhea (GC) screening for men who report receptive anal sex. Despite the availability of nucleic acid amplification tests (NAAT) validated for rectal specimens, compliance with rectal screening in sexual health clinics often remains sub-optimal.

Objective:
To compare the prevalence of rectal CT and GC before and during implementation of a rectal screening evaluation and to compare with other anatomic site infections with CT and GC within and across evaluation periods.

Method:
As part of an ongoing evaluation to compare results of provider-collected versus self-collected rectal specimen for GC/CT NAAT, men who reported receptive anal sex were routinely offered rectal GC/CT testing at a sexual health clinic. Rectal results were compared to other anatomical sites within the study period as well as with rectal results for the three months previously when the evaluation was not implemented. Specimens were tested using previously validated NAATs.

Result:
Between August 1, 2007 and October 15, 2007, there were 1584 clinic visits from men who have sex with men (MSM); 260 (16.4%) were tested for rectal CT and GC. The prevalence of rectal CT was 17.6% (46/260) and rectal GC was 16.9% (44/260). The prevalence of urethral CT was 5.2%; urethral GC 5.9% and pharyngeal GC was 7.5% during the evaluation period. Compared with results from May 1, 2007 through July 15, 2007, there were 1882 MSM clinic visits; 215 (11.4%) were tested for rectal CT and GC. The prevalence of rectal CT was 13.6% (29/214); rectal GC was 15.3% (33/215); urethral CT was 5.0%; urethral GC was 4.0% and pharyngeal GC was 8.2%.

Conclusion:
Compliance with CDC MSM screening guidelines resulted in a 29% increase in the detection of rectal CT.

Implications:
Strategies to implement guidelines should be emphasized in STD clinic settings.