Local Incidence of Jarisch-Herxheimer Reaction in Pregnancy Following Penicillin Treatment for Syphilis: A Case Series

Background: The literature suggests that the Jarisch-Herxheimer (J-H) reaction following antimicrobial treatment of syphilis is common and may precipitate uterine activity. Local practice is to transfer syphilitic parturients beyond gestational age of viability from rural locations to a tertiary care centre for treatment. Study objectives were to delineate local incidence and risk factors for the J-H reaction among pregnant women receiving treatment for syphilis.

Methods: A retrospective chart review was conducted on pregnant women diagnosed with syphilis and treated during pregnancy at a tertiary care centre between 2012 and 2018. J-H reaction was defined as having ≥1 of the following symptoms within 24 hours of antibiotic treatment: fever (temperature ≥38°C), clinical description of a painful or itchy skin lesion, headache, hypotension (systolic blood pressure <90 mmHg), uterine contractions, or fetal heart rate decelerations. Descriptive statistical analysis was performed with mean and median used as measures of central tendency for continuous and categorical data, respectively.

Results: Fifty-eight charts were eligible for inclusion. Mean maternal age was 25.1 (SD 5.6) years, and mean gestational age was 20.4 (SD 9.5) weeks when syphilis was diagnosed. One patient (1/58, 1.7%) met J-H reaction criteria. Mean gestational age at delivery was 37.1 (SD 3.4) weeks. One stillbirth (1.7%) was identified.

Conclusions: The J-H reaction is less common at our centre than the literature suggests. Further research is important to identify risk factors associated with J-H reaction to optimize resource allocation in the context of treatment of syphilis during pregnancy.