Presenting Author:

Roky Truong, Research staff

Principal Investigator:

Brian Mustanski



Rectal STIs, Chlamydia trachomatis, Neisseria gonorrhea, YMSM, HIV/AIDS


Third Floor, Feinberg Pavilion, Northwestern Memorial Hospital

PH59 - Public Health & Social Sciences

Repeat Positivity following Rectal Chlamydia and Gonorrhea Diagnosis in YMSM

AIM: The prevalence of bacterial sexually transmitted infections (STIs) has remained high among young men who have sex with men (YMSM) in the U.S. Limited research, however, has examined demographic and behavioral correlates among those who persistently screen positive for STIs over time, particularly among sexual minority youth. This analysis compares incidence rates of both rectal Chlamydia trachomatis (RCT) and Neisseria gonorrhea (RNT) in a longitudinal cohort while also evaluating the likelihood of retesting positive one year follow-up. We hypothesize that having a positive screen for rectal STI at baseline will increase likelihood of retesting positive for an STI at follow-up. OBJECTIVE: To determine the incidence rates and demographic correlates of RCT and RNG among a cohort of YMSM in Chicago. Additionally, we aim to determine whether a baseline diagnosis of a rectal STI leads to a higher risk of testing positive at one year follow-up. SAMPLE: This study analyzes data from an on-going longitudinal cohort study of YMSM (aged 16 to 29) in Chicago (N=1078) during the period 2015-2017. METHODS: Data were collected at baseline with continuing six-month follow-up visits. At odd-numbered visits (i.e. V1 & V3), participants were screened for RCT and RNG using self-administered testing kits with results reported back to participants within one week. Those who tested positive were referred to clinics for treatment and to receive other sexual health resources. RESULTS: Among 1078 participants at baseline, 174 (16%) tested positive for a rectal STI: 96 (9%) tested positive for RNG and 110 (10.5%) tested positive for RCT. At the one year follow-up, among 808 participants, 130 (16%) again tested positive for a rectal STI – suggesting no change in the incidence rate for infections (p>0.05). Participants who tested positive for rectal STIs at baseline, compared to those who tested negative at baseline, were three times more likely to have also tested positive for rectal STIs follow-up (p<0.0001). Additionally, Black YMSM participants, compared to other YMSM, were 4 more likely to retest positive for RCT or RNG (p<0.001) as compared to white participants. HIV-positive participants, compared to HIV-negative participants, were twice as likely to test positive for rectal STIs at follow up (p<0.001). DISCUSSION: These results suggest that participants who tested positive for rectal STIs at baseline are also those most likely to test positive again at follow-up. Separately, Black and HIV positive YMSM are at greater risk of persistently testing positive. Future research should incorporate treatment history for STIs to develop a better understanding of whether these findings represent untreated infections or re-infections. Further research into the genetic makeup of specific rectal infections may be useful for determining if the infections at follow up are re-infections or wholly new infections