The U.S. Preventive Services Task Force has updated its 2014 statement on screening asymptomatic individuals for chlamydia and gonorrhea infection.
Published online in JAMA, the 2021 version recommends that all sexually active women aged 24 years or younger and at-risk women 25 years or older should be screened for chlamydia and gonorrhea.
As in 2014, the task force made no screening recommendation for men owing to inconclusive evidence of benefit.
With cases of sexually transmitted infections reaching all-time highs, Amy G. Cantor, MD, MPH, of the Pacific Northwest Evidence-based Practice Center at Oregon Health & Science University, Portland, and colleagues noted that chlamydia and gonorrhea are among the most common STIs in this country. According to the Centers for Disease Control and Prevention, 2019 saw approximately 1.8 million reported cases of chlamydia and more than 600,000 of gonorrhea.
In the current analysis of 27 observational and randomized studies comprising 179,515 patients, the USPSTF panel found that, compared with no screening, chlamydia screening was significantly associated with a reduced risk of pelvic inflammatory disease (PID) in young women in 2 out of 4 trials.
The authors cautioned, however, that the magnitude of benefit was relatively small. No studies reported on screening effectiveness in men, except for one reporting rates of epididymitis, and no studies were done on pregnant women for any outcome.
The largest and newest study, the Australian Chlamydia Control Effectiveness Pilot trial of 2018, assessed chlamydia screening against usual care in 180,355 men and women aged 16-29 years in 130 rural Australian primary care clinics. Screening was associated with a reduced risk of hospital-diagnosed PID: the absolute risk was 0.24% for screening versus 0.38% for usual care (unadjusted risk ratio, 0.6; 95% confidence interval, 0.4-1.0). It was not, however, significantly associated with a reduced risk of clinic-diagnosed PID, with an absolute risk of 0.45% versus 0.39% (RR, 1.1; 95% CI, 0.7-18). Nor did it correlate with a risk reduction for clinic-diagnosed epididymitis: 0.26% vs. 0.27% (RR, 0.9; 95% CI, 0.6-1.4).
While risk prediction criteria apart from age were only minimally accurate, testing for asymptomatic chlamydial and gonococcal infections was highly accurate at most anatomical sites, including urine and self-collected specimens, the investigators observed. Age 22 years or younger alone versus multi-item risk criteria demonstrated similar discrimination in a study that included symptomatic and asymptomatic women.
Sensitivity of chlamydial testing was similar at endocervical (89%-100%) and self- and clinician-collected vaginal (90%-100%) sites for women and at meatal (100%), urethral (99%), and rectal (92%) sites for men. It was lower, however, at pharyngeal sites (69.2%) for men who have sex with men (MSM).
Sensitivity of gonococcal testing was 89% or greater for all anatomical samples. False-positive and false-negative testing rates were low across anatomical sites and collection methods.
“Effectiveness of screening in men and during pregnancy, optimal screening intervals, and adverse effects of screening require further evaluation, Dr. Cantor and associates concluded.
In an accompanying editorial, Jeanne Marrazzo, MD, MPH, and Jodie Dionne-Odom, MD, MSPH, of the division of infectious diseases at the University of Alabama at Birmingham, called the guidelines “timely” and “powerful agents of change” that “influence a wide spectrum of health-based metrics, from quality assurance measures to criteria for financial reimbursement.”
They pointed out that men who have sex with men are experiencing historically high rates of gonorrhea, with most infections occurring extragenitally at the pharynx or rectum. In 2019 CDC data, MSM had substantially higher rates of gonorrhea than men who had sex only with women. They recommended that guidelines for men consider STI risk because of sexual relations with men, women, or both.
“Comprehensive screening guidelines for common STIs like chlamydia and gonorrhea could incorporate the limited evidence base for MSM, whether it is regular practice or not,” they wrote, with the same approach for women who have sex with women but may be at risk for chlamydia, particularly if they also have sex with men.
In their view, these latest guidelines appropriately prioritize high-level clinically based data. They pointed, however, to recent progress in understanding the pathogenesis of upper reproductive tract infection in women and the sexual networks behind the current resurgence of STIs in the United States in the failure to manage exposed sex partners.
“Considering these critical advances in the evolution of clinic-based screening guidelines is a work in progress,” they wrote, “the dialogue among basic scientists, clinical trial investigators, and public health professionals to inform the next version of updated USPSTF chlamydia and gonorrhea screening guidelines should start now.”
In the opinion of Jennifer L. Reed, MD, MS, a professor of pediatrics and an emergency medicine physician at Cincinnati Children’s Hospital Medical Center and not involved in the updated statement, the recommendations are very reasonable. “The highest rates of infection occur in females 15-24 years of age, and therefore asymptomatic screening for chlamydia and gonorrhea is imperative at least annually or more often if they are high risk,” she said in an interview.
“I would hope that providers increase their asymptomatic screening as a result of these recommendations and highly consider it in the younger men,” Dr. Reed added. “I see a very high rate of gonorrhea and chlamydia infections.” Her center is studying the implementation of gonorrhea and chlamydia asymptomatic screening for adolescents in the pediatric emergency department, a high-risk patient population that will benefit from STI screening opportunities in nontraditional settings.
This research was funded by the Agency for Healthcare Research and Quality and the Department of Health & Human Services under a contract to support the USPSTF. One statement coauthor reported personal fees from Insmed, Paratek, RedHill, and Spero, as well as grants from Insmed. No other disclosures were reported. Dr. Dionne-Odom reported grants from the National Institutes of Health/National Institute of Child Health and Development. Dr. Reed reported a grant from NIH/NICHD for a pragmatic trial of improving STI detection in the pediatric ED.