Jarisch-Herxheimer reaction 

By usmlevideoss

Key Points 

Jarisch-Herxheimer reaction is a transient clinical phenomenon that usually occurs within 2 – 24 hours of antibiotic treatment of spirochete infections, including syphilis, leptospirosis, Lyme disease, and relapsing fever. 

-it is common in early syphilis, particularly in secondary syphilis, where it can occur in 70-80 % of cases 

Mechanism

The breakdown of dying spirochetes after the use of antibiotics causes the release of endotoxins and cytokines, which enter the patient’s bloodstream and unleash inflammatory reactions. 

Symptoms & Signs  

Abrupt onset of fever, sweating, chills, rigors, headache, nausea and vomiting, tachycardia, hypotension, hyperventilation, myalgia, flushing, pharyngitis, skin rash, tender lymphadenopathy, renal failure, liver failure, cardiac injury, meningitis, psychosis  

Pregnant patients: premature contractions, fetal distress 

Diagnosis 

There is no specific diagnostic test 

CBC: increased circulating neutrophil count 

Treatment 

Mild reaction: self-limiting, often resolve spontaneously within 24 hours 

rest, fluid intake,aspirin or acetaminophen 

Severe: IV fluids, steroids, TNF-alpha antibodies, hospital admission 

fetal monitoring in pregnant patients

Patients should be reminded that the reaction does not signify an allergy to penicillin 

Forewarn the patient about the possibility of a reaction