Non-gonococcal urethritis in men practising "safe" sex

The Duality of Oral Sex for Men Who Have Sex with Men: An Examination Into the Increase of Sexually Transmitted Infections Amid the Age of HIV Prevention

Several studies suggest that the increase in sexually transmitted infections (STIs) among men who have sex with men (MSM) could be due, in part, to human immunodeficiency virus (HIV) risk reduction strategies, which include engaging in oral sex over anal sex. The aims of this study were to evaluate oral sex behaviors and STI diagnoses and to investigate the potential dual role of oral sex as being protective for HIV, yet perpetuating STI transmission among MSM. We analyzed records from 871 MSM presenting to the Rhode Island STI Clinic between 2012 and 2015. We compared outcomes in men engaging in two HIV protective oral sex behaviors: (1) HIV/STI outcomes by men engaging only in oral sex versus those that did not, and (2) HIV/STI outcomes by men engaging in condomless oral sex with 100% condom use for all other sex acts versus those that did not. Men engaging in HIV protective oral sex behaviors were more likely to be HIV negative compared to men not engaging in them (99% vs. 93%, p < 0.01). In contrast, there was no significant difference in STI diagnoses between those that engaged in HIV protective oral sex behaviors and those that did not. The findings provide evidence to support the unique duality of oral sex: decreased risk for HIV and perpetuation of STI risk. Promotion of routine STI testing, including extragenital sites, is critical to address STI prevention among MSM. In the age of HIV prevention, addressing the ambiguous risks of discrete sex acts would be beneficial for both HIV and STI prevention education for MSM.

Peripheral blood T cell proliferative response to chlamydial organisms in gonococcal and non-gonococcal urethritis and presumed pelvic inflammatory disease

OBJECTIVE

To study peripheral blood mononuclear cell (PBMC) proliferative response to Chlamydia trachomatis elementary bodies in (a) controls, (b) various stages of gonococcal (c) and non-gonococcal urethritis, and (d) women with a clinical diagnosis of pelvic inflammatory disease (PID).

METHODS

We categorised 102 men presenting to a GUM clinic with urethritis by organisms (C trachomatis (CT) or Neisseria gonorrhoeae (NG) (both by culture), and whether it was their first (urethritis naive) or subsequent (urethritis experienced) attack. 23 women presenting to the clinic with a clinical diagnosis of PID were also investigated. We measured PBMC proliferative responses to C trachomatis (DK20--an oculogenital strain, serovar E), lysate of McCoy cells (used to propagate chlamydiae), and the recall antigen PPD. Controls were 37 men and women without present or past history of urethritis or chlamydial infection. Results were expressed as the ratio of the stimulation index (SI) obtained with DK20 compared with McCoy cells (DK index), and the ratio of the SI obtained with DK20 compared with PPD (PPD index).

RESULTS

The median SI to DK20 in the urethritis was 12.7 which was significantly higher than the controls (7.6, p < 0.003). The median SI to the recall antigen PPD was similar in the urethritis patients (17.4) and the controls (22.4). All urethritis patient subgroups had a significantly higher DK index and PPD index than the controls. There was no difference in the PPD and DK index between urethritis naive and urethritis experienced patients and between the culture positive and culture negative urethritis subgroups. In PID patients only the PPD index was significantly higher than the controls.

CONCLUSION

Men presenting with urethritis and women presenting with PID both have significantly greater peripheral blood mononuclear cell proliferative responses to the DK20 strain of C trachomatis than controls. A similar T cell proliferative response pattern in urethritis naive patients with either gonococcal or non-gonococcal urethritis could be because low sensitivity of CT culture failed to diagnose some cases of C trachomatis. However, it may also signify earlier exposure of the patients to chlamydial antigens (for example, C pneumoniae), cross reacting antigens such as heat shock proteins from other microbial species, or a "bystander" activation of chlamydia specific memory T cells trafficking through mucosal lymphoid tissue during urethritis. These results suggest evidence of T cell mediated response to C trachomatis cannot be used as a diagnostic tool.