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Jarisch-Herxheimer Reaction — SCE Infectious Diseases MCQ

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HardSTIsJarisch-Herxheimer ReactionSCE Infectious Diseases

Six hours after benzathine penicillin for infectious syphilis, a patient develops fever, rigors, myalgia and transient worsening of lesions. Blood pressure is stable, there is no wheeze or urticaria, and symptoms settle within 18 hours. Which interpretation is correct?

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Correct answer: B — Jarisch–Herxheimer reaction caused by cytokine release after treponemal killing; provide supportive care

The best answer is “Jarisch–Herxheimer reaction caused by cytokine release after treponemal killing; provide supportive care”. Fever, rigors, myalgia and transient lesion worsening within hours of anti-treponemal therapy, without allergic features, is a Jarisch–Herxheimer reaction. It results from inflammatory cytokine release during treponemal killing and is managed with supportive care. It is neither penicillin anaphylaxis nor treatment failure and does not require avoiding beta-lactams.

Reference: BASHH UK syphilis guideline 2024: https://www.bashh.org/resources/25/guidelines_syphilis_2024/