An Update on CDC STI Treatment Guidelines

Treatment guideline updates for sexually transmitted infection (STI) management in women were discussed in detail by experts during the 2021 American College of Obstetricians and Gynecologists (ACOG) Annual Clinical and Scientific Meeting, which was held virtually April 30 to May 2.

Kimberly A. Workowski, MD, FACP, FIDSA, professor of medicine in the Division of Infectious Diseases at Emory University in Atlanta, Georgia, and consultant to the Centers for Disease Control and Prevention (CDC) to coordinate development of the guidelines, described the clinical management of STIs in women, discussed appropriate diagnostic testing and new treatment recommendations, and highlighted evidence-based strategies aimed to address increases in gonorrhea, chlamydia, syphilis, and congenital syphilis.

“STIs are currently epidemic in the United States, and for the sixth year in a row, there’ve been dramatic increases in chlamydia, gonorrhea, and syphilis,” Workowski said. “About 1 in 5 [people] in the United States have an STD [sexually transmitted disease,] and it is a substantial amount of direct medical costs,” including nearly $16 billion each year for new STIs. In particular, congenital syphilis tripled between 2014 and 2018.

Myriad factors are at play regarding the high rates of STIs and hurdles to prevention, Workowski explained. Health disparities and the social determinants of health are primarily to blame and remain potent challenges in prevention. Stigma is also a significant barrier, fostering a lack of provider awareness, education, and training. The COVID-19 pandemic has been an added challenge in STI prevention; clinic closures, antimicrobial and swab shortages, and a focus on telehealth have set effective STI prevention back.

“There’s also limited point-of-care diagnostics [and] an increase in antimicrobial resistance. Our uptake of HPV vaccine has been suboptimal, and there’s also an ongoing syndemic of STI, HIV, viral hepatitis, and substance use disorder,” Workowski said.

The 2021 STD treatment guidelines are anticipated to be released by summer 2021, and Workowski’s presentation covered the highlights of the most recent updates. The guidelines in part focused on antimicrobial stewardship and emerging resistance, as well as updated treatment regimens and prevention recommendations for gonorrhea, chlamydia, trichomonas, and pelvic inflammatory disease

Clinical Prevention Guidance

The first part of the updated guidelines focuses on clinical prevention guidance, including updates on:

1. behavioral and biologic risk assessments;
2. the importance of HPV vaccination;
3. prevention methods, including condoms, circumcision, and emergency contraception;
4. pre-exposure and post-exposure prophylaxis;
5. multipurpose prevention technologies;
6. retesting (chlamydia, gonorrhea, trichomonas) 3 months post therapy; and
7. partner services.

Genital, Anal, or Perianal Ulcers

In the United States, herpes and syphilis are the most common infectious cause of ulcers. “These really differ depending on which geographic area and population that you serve,” Workowski said.

Specific evaluations include darkfield/syphilis serology, nucleic acid amplification for herpes, and herpes type specific serology. “Most clinicians don’t have the availability of darkfield, but we do have syphilis serology,” Workowski said.

Genital Herpes

Polymerase chain reaction (PCR) is the preferred diagnostic test for genital herpes, according to Workowski, but culture remains useful if a clinician suspects a patient may have acyclovir-resistant herpes.

Type-specific serologic testing is used in patients with recurrent genital lesions with a negative PCR or culture, signs of infection but no lab test documenting herpes, and a partner with genital herpes. “The reason why the serologic testing is not commercially a universal recommendation is because there are problems with the specificity of the test, and there will be more specific language regarding serologic 2-step testing in terms of the confirmation of herpes,” Workowski said.

The guidance also has new sections on herpes simplex virus types 1 and 2 as well as hepatitis because of herpes.

Syphilis

Rising rates of syphilis have been seen over the past several decades. “What I really want to point out is the increase in the female rate, from about 2010 to the present,” Workowski said. “If we look at what’s happening, we really see the intersection of methamphetamine [and] heroin use associated with this increase in syphilis.”

There also has been a dramatic increase in congenital syphilis between 2010 and 2018. Workowski pointed to several missed opportunities for preventing congenital syphilis, including:

1. no timely prenatal care and no timely syphilis testing,
2. no timely syphilis testing despite receipt of timely prenatal care,
3. no adequate treatment despite a timely syphilis diagnosis,
4. late seroconversion during pregnancy,
5. clinical evidence of congenital syphilis despite adequate maternal treatment, and
6. insufficient information.

Diagnosing syphilis requires serologic testing—either the traditional algorithm of a nontreponemal antibody test followed by a treponemal antibody test or the reverse sequence, according to Workowski. “The reverse sequence algorithm [is] actually much more sensitive at picking up early disease, but there’s a high number of false positive with this test,” she explained. The guidelines go into detail about the use of each algorithm, as well as their use and interpreting in pregnancy.

Syphilis in Pregnancy/Congenital Syphilis

For pregnant women, the new guidelines emphasize the importance for those with higher risk factors to get retested at 28 weeks and again at delivery. Risk factors include:

1. multiple partners,
2. sex with drug use or transactional sex,
3. late to prenatal care (after the second trimester) or no prenatal care,
4. methamphetamine/heroin use,
5. incarceration, and
6. unstable housing/homelessness.

There also is revised language that discusses reinfection or treatment failure, “really defined as a 4-fold increase in titer post treatment that’s sustained,” Workowski said.

As for syphilis treatment, Workowski explained that there are no changes, as investigators are still examining the role of enhanced therapy for patients who are not pregnant. A randomized clinical trial is working on addressing enhanced therapy.

Reference

Workowski K. Sexually transmitted infections guidelines update. Presented at: The American College of Obstetricians and Gynecologists 2021 Annual Clinical and Scientific Meeting; April 30 to May 2, 2021; virtual.