Late-Diagnosed Congenital Syphilis in a Toddler: Successful Management with Ceftriaxone<br>—A Case Report and Literature Review

Background: Congenital syphilis continues to be a re-emerging global health issue despite the availability of effective screening and prevention programs. Penicillin G remains the first-line and only CDC-recommended treatment; however, in resource-limited settings, its unavailability may necessitate alternative therapies. We report a case of congenital syphilis diagnosed beyond infancy, successfully managed with ceftriaxone due to unavailability of penicillin. Case Presentation: A 2-year-old female was diagnosed with congenital syphilis following retrospective family-based screening after her father presented with symptoms of secondary syphilis. The father had been unknowingly exposed to syphilis approximately three years prior, before the child’s conception. The mother’s antenatal syphilis screening during pregnancy was documented as negative. One year after the child’s birth, the father developed a palmar rash and genital ulcers. Both parents were found to have reactive treponemal tests, prompting serologic testing of their children. While the two older sons tested negative, the youngest child (our patient) tested positive for both treponemal and non-treponemal antibodies. She was clinically well, with no signs of late congenital syphilis. Maternal RPR titers from pregnancy were not available. Further evaluation excluded neurosyphilis. Due to the unavailability of benzathine and aqueous penicillin formulations, the patient was treated with IV ceftriaxone (100 mg/kg/day for 10 days). She showed excellent tolerance and demonstrated a favorable serologic response on follow-up. Discussion: This case underscores the diagnostic challenges of congenital syphilis in the absence of maternal symptoms and highlights the importance of postnatal screening in high-risk families. While penicillin remains the gold standard, ceftriaxone may be a viable alternative in select cases when penicillin is unavailable. A literature review is provided to contextualize treatment options and outcomes. Conclusion: In settings where penicillin is inaccessible, ceftriaxone may offer an effective off-label alternative for congenital syphilis, provided that close follow-up and serologic monitoring are ensured.