Dynamics of plasma levels of specific IgE in chlorhexidine allergic patients with and without accidental re‐exposure

Abstract

Time from reaction should be considered when interpreting specific IgE results. Specific IgE is >0.35 kUA/L in most patients at time of reaction but should be repeated after a few weeks/months if negative. The optimal sampling time seems to be >1 month and <4 months. A value <0.35 kUA/L neither excludes allergy nor implies loss of reactivity in previously sensitized patients. Re-exposures are common, often iatrogenic, and can cause a rebound in specific IgE.

Anaphylaxis after disinfection with 2% chlorhexidine wand applicator

“…Interestingly, his specific IgE tests remained negative on repeat testing over 6 months. A study of patients with chlorhexidine anaphylaxis showed that only 1 out of 23 had a negative specific IgE test 2–4 months after the reaction 28. The reason for the negative results in our patient may be a reflection of the fact that patients with renal failure appear to have lower levels of IgE in general 29…”

Specialist perioperative allergy clinic services in the UK 2016: Results from the Royal College of Anaesthetists Sixth National Audit Project

“…Two‐thirds of children had to wait more than 12 weeks to be seen, while more than half of adults waited more than 8 weeks to be seen which may impact on test sensitivity. Drug sensitization to chlorhexidine is known to be transient so these delays in assessment run the risk of missing important sensitizations and compromising the diagnostic algorithm.…”

Undesirable Effects of Some Topical Antiseptics Chemical, pharmacological and dermatological aspects

“…Optimum sampling time appears to be between 1-4 months. The authors noted, however, that levels <0.35KUA/L could not be used to rule out hypersensitivity to chlorhexidine [7]. Patients with eczema, especially those with leg ulcers or leg eczema, are especially prone to chlorhexidine allergies [8].Anaphylactic reactions have been reported after the use of chlorhexidine including during normal bladder catheterization [9,10].Irreversible corneal injuries and opacification attributed to chlorhexidinegluconate 4% topical preparation, are reported in 4 female patients, aged 9 months to 83 years, in whom the drug was accidentally introduced into the eye during surgical preparation.…”