Congenital syphilis — preventable, yet increasing: 10-year data from a secondary hospital in Azores, Portugal

Abstract

Introduction: Congenital syphilis (CS), which resultss from vertical transmission of Treponema pallidum, presents a broad spectrum of clinical manifestations in neonates. It’s effective control relies on early maternal diagnosis and treatment during pregnancy.
Materials and methods: We conducted a retrospective and descriptive study of CS cases in the Neonatal Intensive Care Unit (NICU) of Hospital do Divino Espírito Santo in Ponta Delgada, Azores, between 2013 and 2022. We reviewed the medical records of all discharged patients with CS, defined according to the 2021 Centers for Disease Control and Prevention guidelines. Demographic, clinical, and laboratory data on both mothers and newborns were collected.
Results: Twenty newborns with suspicion of CS were admitted to the NICU between 2013 and 2022. The incidence of CS was stable until 2020, with 0–2 cases per year. From 2020 onwards, there was an exponential increase in the number and severity of cases. Fifteen pregnancies were followed up exclusively in primary care, while four were monitored through outpatient appointments offered by the hospital’s high-risk obstetrics service. Mothers were adequately treated in seven cases. Four newborns were born before 37 weeks of gestation, and two between 28 and 32 weeks of gestation. Four newborns presented with severe forms of CS, one of which died. The most common manifestation of CS was jaundice (11/55%); abnormal hepatic parameters were observed in 14/70% of the newborns. Bone involvement was seen in 4/20% newborns. All were treated with penicillin G (median of 14 days, 95% Confidence Interval [CI] 10-14), and CS was confirmed in nine cases (45%).
Discussion and conclusions: An increase in CS was observed from 2020 to 2022, with most pregnancies lacking proper referral or treatment, which is in line with international reports. Prompt diagnosis and appropriate treatment of the mothers can prevent this serious and potentially fatal disease in newborns.