Keep Screening Women for Chlamydia and Gonorrhea, Says USPSTF

The U.S. Preventive Services Task Force (USPSTF) reaffirmed its 2014 guidance on recommending chlamydia and gonorrhea screening in all sexually active women ages 24 and younger, and for older women at increased risk for infection, regardless of pregnancy status (B rating).

No luck for asymptomatic men, however, as there remain insufficient data on the benefits and harms of screening (I rating).

The Task Force concluded “with moderate certainty” that screening for both sexually transmitted infections (STIs) in these women has “moderate net benefit,” they wrote in JAMA, but noted that there was little evidence for the effectiveness of screening in low-risk women.

Sexually active girls and women ages 15 to 24 are at highest risk for chlamydia and gonorrhea infection, with risk factors in women 25 and older including a prior STI, multiple sexual partners, inconsistent condom use, a history of incarceration, or prostitution. These STIs frequently develop into pelvic inflammatory disease (PID), which is associated with various complications.

In implementing the guidance, “clinicians should consider the communities they serve and may want to consult local public health authorities for information about local epidemiology and guidance on determining who is at increased risk,” the Task Force said.

In men, chlamydia and gonorrhea infections are typically asymptomatic but can lead to urethritis, epididymitis, and proctitis, and also increase the risk for acquiring HIV.

“These recommendations are timely, given that the most recent CDC report on sexually transmitted infection surveillance noted that chlamydia and gonorrhea rates in the U.S. in 2019 were at a 20-year high, with overall rates of 553 cases per 100,000 population and 188 per 100,000, respectively,” Jeanne Marrazzo, MD, MPH, and Jodie Dionne-Odom, MD, MSPH, of the University of Alabama at Birmingham, wrote in an accompanying editorial.

The USPSTF noted that their recommendations apply to biological sex at birth, not an individual’s current gender identity.

Marrazzo and Dionne-Odom said that “a more broadly relevant approach would be to develop evidence-based guidelines for screening people who identify as nonbinary, but to be inclusive when developing pathogen-specific guidelines in general or, at a minimum, to specifically refer to cis-gender women or men.”

Cantor told MedPage Today that “studies are needed that provide more information on certain groups, specifically men who have sex with men, sexually active men younger than age 24 years, men residing in high-prevalence communities, sexual and gender minority populations, and pregnant persons.”

She added that more research is also needed “on screening in diverse populations such as non-Hispanic Black individuals, Alaska Native/American Indian, and Hispanic women; to help evaluate the effect of differential access and effective prevention strategies for these populations, which could reduce racial and ethnic disparities.”

In an evidence review involving 27 studies that accompanied the new USPSTF guidance, chlamydia screening was associated with a decreased risk for PID in two of four clinical trials, reported Amy Cantor, MD, MPH, of the Oregon Health & Science University in Portland, and colleagues.

A new randomized cluster trial — the Australian Chlamydia Control Effectiveness Pilot trial — added to the evidence base as well, and showed that chlamydia screening was associated with fewer hospital diagnoses of PID compared to no screening (0.24% vs 0.38%, respectively; relative risk 0.6, 95% CI 0.4-1.0).

“Key differences between the current review and the prior review are that the current review combined all populations, including pregnant persons, into a single analytic framework; evaluated the accuracy of risk stratification and screening strategies for identifying persons at increased risk; and focused evaluation of diagnostic accuracy on anatomical site-specific testing,” the USPSTF said.

In studies examining risk prediction tools, similar high sensitivity of chlamydia tests were shown for women at various sites:

• Endocervical: 89-100%
• Vaginal (self- or clinician-collected): 90-100%
• Meatal: 100%
• Urethral: 99%
• Rectal: 92%

Gonococcal testing had high sensitivity (89% or greater) at all anatomical sites, with few false positives or false negatives.

Cantor’s group acknowledged that they did not review the diagnostic accuracy of assays. Also, as many studies were conducted at STI clinics, their findings may not be generalizable to primary care settings.