The return of congenital syphilis: Disease spectrum and modifiable factors in a semi-rural regional hospital in KwaZulu-Natal Province, South Africa.

BACKGROUND: Despite the World Health Organization's current focus on eliminating congenital syphilis (CS) as part of its triple elimination strategy, the incidence of CS in South Africa (SA) is increasing. This highly preventable disease causes high morbidity and mortality. Recent local data on the clinical presentation of CS and modifiable factors associated with vertical transmission are scarce. OBJECTIVES: To describe the maternal and neonatal characteristics of symptomatic and asymptomatic neonates admitted with CS, and to identify the modifiable factors leading to CS infection. METHODS: We conducted a retrospective review of all CS cases diagnosed in live-born infants managed at General Justice Gizenga Mpanza Regional Hospital in KwaZulu-Natal Province, SA, between 1 December 2019 and 31 December 2020, describing clinical presentation and modifiable factors that contributed to the occurrence of CS. Outcomes were compared between symptomatic and asymptomatic infants, and clinical features were compared between surviving and non-surviving infants. RESULTS: We recorded 54 cases of CS out of 7 535 live-born infants (0.7%), including two sets of twins. Mothers of infants with CS were more likely to be living with HIV (52% (n=27) v. 38% of all mothers delivering live-born infants at our facility (p=0.032)), and less likely to have attended antenatal care (ANC): 19% (n=10) did not attend ANC, v. 2% overall (p=0.000). Neonatal death occurred in 7 (13%) infants with CS. Forty (74%) of the infants were symptomatic, with hepatosplenomegaly being the most common finding (68% of infants with CS). In total, 78 modifiable factors contributing to CS were identified, and grouped into maternal factors and factors related to timing of diagnosis, the healthcare system, testing and hospital or clinic visits. For 18 mothers (33% of modifiable factors), the result of the syphilis test conducted during pregnancy was not traced, or no treatment was commenced; 14 (27%) seroconverted during pregnancy after an initial negative booking test. CONCLUSION: Our study confirms high morbidity and mortality associated with CS. We recommend the use of point-of-care rapid diagnostic tests (mono syphilis or dual HIV/syphilis) at regular intervals throughout pregnancy. Elimination of CS is challenging, with a high percentage of mothers of neonates with CS not attending ANC.