Jarisch-Herxheimer Reaction (Last Updated - 5/17/2005)
-a usually mild & transient reaction which follows the initial anti-microbial tx. for spirochetal infex.:
-Syphilis:
-occurs in 50% w/ primary syphilis
-occurs in 90% w/ 2nd-ary syphilis
-occurs in 25% w/ early latent syphilis
-Relapsing Fever:
-esp. w/ louse-borne relapsing fever (LBRF)
-Leptospirosis
-Lyme Disease --> occurs in 15%
Clinical / Laboratory S/S's:
-fevers
-chills
-myalgias
-HA's
-tachycardia
-increased resp. rate (RR)
-increased peripheral neutrophil count
-vasodilation
-mild hypotension
-onset of s/s's occurs w/in 2 hrs. of initiation of tx.
-fevers peak @ ~7 hrs. post-initiation of tx. and defervescence occurs w/in 12-24 hrs.
-recent research suggests the cause as inflammatory mediators (esp. TNF-alpha)
-assoc. w/ increased cytokine release into plasma:
1) TNF-alpha --> enormous amounts
2) IL-6
3) IL-8
4) CRP (C-Reactive Protein)
Treatment:
-supportive --> bed rest & ASA
-monitor fluid balance, BP and myocardial function
-steroids & NSAID's --> NOT required
-new research suggests that pts. undergoing anti-microbial tx. for spirochetal infex. may benefit from pre-tx. w/ Ab's to TNF-alpha
-suppresses most s/s's
-NOT recommended tx. yet
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References:
Harrison's Principles Of Internal Medicine: 15th Edition. 2001: pg. 1052,1056-1057,1059,1061,1064