Prevalence of pharyngeal Chlamydia trachomatis and Neisseria gonorrhoeae among heterosexual men in Japan

Antimicrobial susceptibilities of Chlamydia trachomatis isolated from the urethra and pharynx of Japanese males

OBJECTIVES

Sexually transmitted infections due to Chlamydia trachomatis (C. trachomatis) are a worldwide public health problem. The aim of this study was to investigate the drug susceptibilities of C. trachomatis strains isolated from the urethra and pharynx of Japanese males.

METHODS

Urethral and pharyngeal swabs were collected between 2013 and 2014 from Japanese males with urethritis. Using a McCoy cell line, 18 chlamydial strains were isolated from urethra in 18 patients and 7 from the pharynx in 7 of the 18 patients. The minimum inhibitory concentrations (MICs) of levofloxacin (LVFX) and azithromycin (AZM) were measured using the standard method of the Japanese Society of Chemotherapy.

RESULTS

The MICs of LVFX and AZM against urethral chlamydial strains were 0.125-0.5 μg/mL and 0.125-0.25 μg/mL, respectively. In pharyngeal strains, the MICs of LVFX and AZM were 0.125-0.25 μg/mL and 0.125-0.25 μg/mL, respectively. In 7 patients with chlamydial strains isolated from both the urethra and pharynx, the MICs of LVFX between these strains were identical in 3 of 6 patients (no growth was observed for one pharyngeal strain), while the MICs of AZM between these strains were identical in all 6 patients (not performed for one patient).

CONCLUSIONS

Our data suggest that C. trachomatis strains isolated from the urethra and pharynx of Japanese males are susceptible to LVFX and AZM. Although measuring the MICs of chlamydial strains is labor intensive, it is a significant surveillance tool for treating chlamydial infections and preventing the spread of STIs.

New treatment options for infections caused by increasingly antimicrobial-resistant Neisseria gonorrhoeae

The emergence of high-level resistance to ceftriaxone is giving rise to serious concern about absence of effective treatment options to cure gonococcal infections. Increasing the dosage regimen can be applied to ceftriaxone and azithromycin, but the emergence of high-level resistance has already been reported. Spectinomycin is another active drug but has low efficacy in the treatment of pharyngeal gonorrhoea. Conventional antibiotics could be introduced for gonococcal treatment, but they have some limitations, such as the absence of clinical trials and breakpoint. Combining antibiotics is another promising method to cure patients and to prevent the emergence of resistance. The most important strategy to maintain the efficacy of antibiotics is rapid detection and dissemination control of novel resistant isolate.

Diagnosis and Management of Uncomplicated Chlamydia trachomatis Infections in Adolescents and Adults: Summary of Evidence Reviewed for the 2015 Centers for Disease Control and Prevention Sexually Transmitted Diseases Treatment Guidelines

In preparation for the 2015 Centers for Disease Control and Prevention (CDC) Sexually Transmitted Diseases (STD) Treatment Guidelines, the CDC convened an advisory group in 2013 to examine recent abstracts and published literature addressing the epidemiology, diagnosis, and management of STDs. This article summarizes the key questions, evidence, and recommendations for the diagnosis and management of uncomplicated Chlamydia trachomatis (CT) infection in adolescents and adults that were considered in development of the 2015 CDC STD Treatment Guidelines. The evidence reviewed primarily focused on CT infection risk factors in women, clinical significance of oropharyngeal CT detection, acceptability and performance of CT testing on self-collected specimens in men, performance of CT point-of-care tests, efficacy of recommended and investigational CT infection treatments, and timing of test of cure following CT infection treatment in pregnant women.

Extragenital Infections Caused by Chlamydia trachomatis and Neisseria gonorrhoeae: A Review of the Literature

In the United States, sexually transmitted diseases due to Chlamydia trachomatis and Neisseria gonorrhoeae continue to be a major public health burden. Screening of extragenital sites including the oropharynx and rectum is an emerging practice based on recent studies highlighting the prevalence of infection at these sites. We reviewed studies reporting the prevalence of extragenital infections in women, men who have sex with men (MSM), and men who have sex only with women (MSW), including distribution by anatomical site. Among women, prevalence was found to be 0.6–35.8% for rectal gonorrhea (median reported prevalence 1.9%), 0–29.6% for pharyngeal gonorrhea (median 2.1%), 2.0–77.3% for rectal chlamydia (median 8.7%), and 0.2–3.2% for pharyngeal chlamydia (median 1.7%). Among MSM, prevalence was found to be 0.2–24.0% for rectal gonorrhea (median 5.9%), 0.5–16.5% for pharyngeal gonorrhea (median 4.6%), 2.1–23.0% for rectal chlamydia (median 8.9%), and 0–3.6% for pharyngeal chlamydia (median 1.7%). Among MSW, the prevalence was found to be 0–5.7% for rectal gonorrhea (median 3.4%), 0.4–15.5% for pharyngeal gonorrhea (median 2.2%), 0–11.8% for rectal chlamydia (median 7.7%), and 0–22.0% for pharyngeal chlamydia (median 1.6%). Extragenital infections are often asymptomatic and found in the absence of reported risk behaviors, such as receptive anal and oral intercourse. We discuss current clinical recommendations and future directions for research.

Should we screen heterosexuals for extra-genital chlamydial and gonococcal infections?

Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) are two of the most prevalent bacterial sexually transmitted infections in the UK. Although the high burden of extra-genital infections with GC and CT in men who have sex with men has been well established, a significant number of extra-genital site infections with CT and GC could similarly be present in heterosexual women. For this reason we started to routinely offer extra-genital site testing for GC and CT in all patients attending our sexual health clinic who reported having had receptive anal sex and/or giving oral sex. This followed a review of current evidence by the clinical team and a change in local testing policy. This study not only confirmed a large reservoir of extra-genital infection amongst men who have sex with men, but also demonstrates that a comparable reservoir of extra-genital infection is present amongst heterosexual women. Our study adds to the mounting evidence that extra-genital site testing in heterosexual women should occur when oral or anal sexual activity is reported.