Congenital syphilis: a revision of the cases over the last 18 years in a referral hospital in Lisbon

Abstract

Introduction: Congenital syphilis is a preventable disease and its persistence reflects a failure in prenatal care delivery systems. Objectives: To identify demographic maternal characteristics, risk factors and clinical features of congenital syphilis. The secondary outcome was to describe the symptomatic cases of congenital syphilis. Methods: Retrospective study of all the children born, between 1997-2015, to syphilis seropositive women. We collected data regarding sociodemographic characteristics, maternal VDRL (Venereal Disease Research Laboratory) titers, co-infections and treatment during pregnancy, clinical features, treatment and follow-up. Results: From a total of 80,639 newborns, 310 mothers and 225 babies had positive VDRL titers. The prevalence risk for congenital syphilis was 0.27%, higher between 2003-2008. Observed maternal characteristics were: 3.9% young mothers (< 20 y), 45.2% African origin, 12.5% basic educational levels, 14.5% unemployed, 6.5% co-infected with human immunodeficiency virus (HIV), 4.7% drug abuse. Prenatal care coverage was provided in 82.9% of the mothers, with only 52.9% adequately treated. Maternal syphilis was classified in: 21.6% early, 21.6% late, 56.8% undetermined. The newborns were classified in: 13.2% highly probable, 41.6% possible and 45.2% less likely. There were four cases of symptomatic congenital syphilis, 3 of them with neurosyphilis. 96% were treated with penicillin. 165/310 (53%) had an adequate follow-up, and the mean age for a negative VDRL titer was at 5.6 months of age. Conclusions: The high percentage of women inadequately treated alerts to the importance of improving prenatal care. Neurosyphilis is a rare and severe presentation of congenital syphilis; screening is essential to avoid late cases or sequels.