Congenital Syphilis: The Cascade of Care in Different Case Scenarios, in a Population of High Social Vulnerability in Brazil

OBJECTIVE: To describe missed opportunities in the prevention of congenital syphilis (CS) and to analyze antenatal factors associated with clinical and/or laboratory manifestations at birth in a cohort of CS neonates in Brazil. METHODS: This cohort study included 240 neonates evaluated for CS between 2016 and 2021. Neonates were categorized as (1) Infected-clinical, laboratory or imaging findings compatible with CS or a Venereal Disease Research Laboratory titer ≥4-fold the maternal titer; (2) Reported-reactive Venereal Disease Research Laboratory (maternal and neonate samples) without clinical/laboratory abnormalities and maternal inadequate or absent treatment; and (3) Exposed-adequate maternal treatment and no signs of CS at birth. Maternal and perinatal variables were collected and compared across groups. RESULTS: Among the 240 neonates, 55% were male and 69% non-White. Although 94% of mothers received antenatal care (mean 7.3 visits), only 72% were treated for syphilis, and several received inadequate or delayed treatment. Thirty-three neonates (14%) met criteria for CS infection; 64 (26%) were reported and 143 (60%) were classified as exposed. Infected neonates presented with neurosyphilis (18%), bone abnormalities (6%) or nonspecific signs, including low birth weight, prematurity and hepatomegaly. Multivariate analysis identified maternal recreational drug use (odds ratio = 5.75; 95% confidence interval: 1.20-27.51) and lack of partner treatment during pregnancy (odds ratio = 3.48; 95% confidence interval: 1.08-11.23) as independent risk factors for neonatal classifications as CS infected. CONCLUSIONS: A significant proportion of CS cases occurred due to inadequate maternal management (64/97, 67%). Interventions must prioritize comprehensive maternal-partner management and consider behavioral risk factors in the CS cascade of care.