One hour after receiving intramuscular benzathine penicillin for secondary syphilis, a patient develops rigors, high fever, tachycardia and hypotension. The cytokine-mediated mechanism responsible for this reaction is:
- A Release of treponemal lipoproteins triggering tumour necrosis factor alpha and interleukins ✓
- B IgE-mediated mast cell degranulation against penicillin haptens
- C Immune complex deposition activating the classical complement pathway
- D Direct toxic effect of penicillin on myocardial contractility
Correct answer: A. Release of treponemal lipoproteins triggering tumour necrosis factor alpha and interleukins
Explanation
The Jarisch-Herxheimer reaction is an acute febrile response occurring within hours of starting effective therapy, classically penicillin in secondary syphilis. Massive killing of treponemes releases lipoproteins that stimulate monocytes to release tumour necrosis factor alpha, IL-6 and IL-8, causing fever, rigors and hypotension. It is self-limiting and managed supportively; it is not an allergic reaction to the drug.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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