Syphilis screening is recommended in all asymptomatic, nonpregnant adults and adolescents, including patients coinfected with other sexually transmitted infections (STIs), according to a statement from the U.S. Preventive Services Task Force (USPSTF) published in JAMA.
The USPSTF found “convincing evidence” that syphilis screening in asymptomatic, nonpregnant persons “provides substantial benefit,” according to the statement, an update to the task force’s 2004 recommendations on syphilis screening. “Effective treatment with antibiotics can prevent progression to late-stage disease, with small associated harms, providing an overall substantial health benefit.” The recommendation to screen all at-risk persons received an A recommendation from the USPSTF.
Since 2000, the incidence of cases of primary and secondary syphilis has been increasing; 19,999 cases were reported in 2014. Untreated syphilis progresses to late-stage syphilis in 15% of cases. Symptoms of late-stage syphilis include the development of inflammatory lesions throughout the body, leading to cardiovascular or organ dysfunction. Neurosyphilis may occur at any stage of the disease, and may result in blindness, paresis, tabes dorsalis, and dementia.
Based on 2014 surveillance data, men who have sex with men (MSM) and both men and women living with HIV have the highest risk of contracting a syphilis infection. Overall, men accounted for 90.8% of all cases of primary and secondary syphilis. Data showed that 61.1% of all cases of primary and secondary syphilis occurred among MSM; one-half of all MSM diagnosed with syphilis were also coinfected with HIV. In particular, men between the ages of 20 and 29 years had the highest prevalence rate – nearly 3 times higher than the average population of US males.
The most common screening test for syphilis is a combination of nontreponemal and treponemal antibody tests. The USPSTF found that screening algorithms with high sensitivity and specificity are available to accurately detect syphilis. Early detection and treatment lead to substantial health benefits by curing any existing syphilis infection, preventing manifestation of late-stage syphilis, and preventing sexual transmission to others. No direct evidence of harms of screening was found, although the possibility of false-positive results does exist.
“Clinicians should be aware of the prevalence of infection in the communities they serve, as well as other sociodemographic factors that may be associated with increased risk of syphilis infection,” wrote the recommendation authors. “Factors associated with increased prevalence … include history of incarceration, history of commercial sex work, certain racial/ethnic groups, and being a male younger than 29 years.”
Treatment guidelines published by the CDC in 2015 recommend parenteral penicillin G benzathine for the treatment of syphilis. Dosage will vary based on disease stage and patient characteristics.
“The current resurgence of syphilis is particularly disheartening given the tools available to control the infection and the significant benefits of doing so,” wrote Meredith E. Clement, MD, Division of Infectious Diseases at Duke University Medical Center in Durham, NC, in a JAMA editorial.
“[S]erologic syphilis screening is highly sensitive and specific … is inexpensive and technically simple, and has minimal potential for harm,” Dr Clement concluded. “These factors argue for much more widespread and comprehensive screening of groups at high risk for syphilis. Because the treatment of early syphilis is also highly effective, identifying untreated persons by means of the recommended screening strategy has great potential for both eliminating the consequences of later-stage infection and substantially reducing transmission from those with early infection.”
- US Preventive Services Task Force (USPSTF). Screening for syphilis infection in nonpregnant adults and adolescents. US Preventive Services Task Force Recommendation Statement. JAMA. 2016;315(21):2321-2327; doi: 10.1001/jama.2016.5824
- Clement ME, Hicks CB. Syphilis on the rise. What went wrong? JAMA. 2016;315(21):2281-2283; doi: 10.1001/jama.2016.7073