Why Can’t We Eradicate Congenital Syphilis?

The epidemic of congenital syphilis (CS) in the United States continues unabated, a tragic indicator of the lack of control of syphilis in many of our communities. Despite evidence-based recommendations for screening all pregnant women and the availability of highly effective penicillin therapy, CS cases continue to increase in the United States, disproportionally affecting racial minorities.¹  The national rate of CS in 2019 was 48.5 per 100 000 live births, a 41.4% increase relative to 2018 and a 291.1% increase relative to 2015.¹  There were 94 syphilitic stillbirths and 34 additional CS-related infant deaths.¹  Although more common in western and southern states, the 1870 cases of CS reported in 2019 were from 43 states and the District of Columbia.²  This preventable infection may result in miscarriage, stillbirth, premature birth, or life-threatening fetal or neonatal illness, but, more commonly, it is completely silent and identified only through appropriate maternal and newborn testing. Failure to diagnose and treat or delays in treatment of syphilis during pregnancy and after the neonatal period can result in more serious disease and lifelong morbidity. In this issue of Pediatrics, Kimball et al³  alert us to an additional challenge for health care professionals who care for children: the increasing number of infants diagnosed with CS after newborn nursery discharge, which is in large part because of the continuing failure to identify and/or expeditiously manage pregnant women with syphilis and their newborns.

Each CS case represents a missed opportunity within public health and health care systems.⁴  Factors associated with the persistence and reemergence of CS are well described.^4,5  In 2019, the most common missed opportunities were a failure to provide adequate maternal syphilis treatment despite receipt of a timely diagnosis (40.2%) and a lack of optimal prenatal care and subsequent lack of recommended testing (36.3%).¹  Also identified were late seroconversion during pregnancy, lack of syphilis testing despite receipt of adequate prenatal care, and failed maternal therapy.¹  Increasing rates of primary and secondary syphilis in the community have also been associated with methamphetamine use and the opioid epidemic.^6,7  Rarely, a pregnant woman may acquire syphilis near the time of delivery and transmit Treponema pallidum to the fetus before she has mounted a detectable serological response to enable identification of the infected newborn.⁸  In this instance, pediatric health care professionals need to be aware of the later presentation of CS.

Kimball et al³  report that, from 2014 to 2018, 84 (2.2%) of the 3834 infants diagnosed with CS were diagnosed beyond the neonatal period, 68 (80.9%) of whom were symptomatic. The median age at diagnosis was 67 days. Although the majority of women received prenatal care, failure to identify infants with CS before hospital discharge was related to 2 key factors: inadequate adherence to screening and treatment guidelines and failure to identify women for whom repeat screening at 28 weeks’ gestation and at delivery is recommended. Forty-two percent of the mothers were not diagnosed with syphilis until after delivery, and more than one-half of these were identified after their infant’s diagnosis. Compounding these failures, 9% of the infants did not receive the treatment recommended for CS. The delay in diagnosis in these infants resulted in the development of symptomatic disease, predisposing them to more severe clinical manifestations and the risk for late and permanent sequelae.

In a recent study,⁹  researchers found that only 50% of pregnant women with syphilis reported known risk factors for syphilis exposure, highlighting the limitations of using a risk-based strategy to identify individuals who require repeat serological testing at 28 weeks’ gestation and at delivery. Also, specific guidance on a number or rate of primary and secondary syphilis within a community that would constitute a high burden of disease area is not standardized or readily available to providers who are making clinical decisions. It is time to move from these failing strategies to testing all pregnant women 3 times during pregnancy: at the first prenatal visit, at 28 weeks’ gestation, and at delivery in any area where syphilis is occurring.

The increasing number of infants born with CS is a public health emergency. Many of us have sadly witnessed the loss of life and severity of disease that result from this preventable infection. All 3 authors of this commentary have seen infants diagnosed with CS beyond the neonatal period.

To reduce the incidence of CS in the United States, health care providers should collaborate with public health agencies to educate the public on the local epidemiology of syphilis, use every health care encounter to identify and treat persons with syphilis, with special attention to women with substance-use disorders who are less likely to seek prenatal services, and work closely with those responsible for the care of pregnant women to advocate for appropriate screening of all pregnant women. In addition, because syphilis is a reportable condition in all 50 states, health care providers need to establish close relationships with their local health department, which can provide any treatment history and locate infected pregnant women for treatment. To manage infants exposed to syphilis in utero or with CS, providers need to be familiar with Centers for Disease Control and Prevention¹⁰  and American Academy of Pediatrics Red Book¹¹  guidelines for evaluation and management of infants born to a mother with treated, untreated, or inadequately treated syphilis and for infants who present with CS after nursery discharge. The report by Kimball et al³  is a stark reminder that prompt treatment of pregnant women with syphilis and knowledge of mother’s serology status at delivery are crucial to identify infants at risk for, or with, CS. Rapid point-of-care testing for syphilis may be helpful in delivery rooms.

Regrettably, we cannot eradicate CS until we are able to address the continuing failure to control syphilis in the community, but we can reduce the risk of CS by identifying and promptly treating all pregnant women with syphilis and treating asymptomatic infants with CS before they become symptomatic. Kimball et al³  remind us of the importance of core public health functions to help identify systemic failures that affect our patients and their families as well as the need to implement new strategies to control this reemerging disease. With it, we are tasked, yet again, with being educators and advocates for our most vulnerable patients.

CS

congenital syphilis