Allergological work-up in epidermal necrolysis appears safe

When allergy skin testing is performed on patients with epidermal necrolysis (EN) by a specialist it is safe and may be helpful when deciding on reintroducing essential drugs, according to a study.

Patch tests (PTs), skin prick tests (SPTs), intradermal tests (IDTs), or drug provocation tests (DPTs) were done on 113 patients with ENs and retrospectively reviewed.

There was a median of 7.9 months from the time of EN to hypersensitivity work-up.

All patients had PTs done, with 22 (19.5%) having positive results. The only factors associated with positivity were ALDEN score and drug class.

One of the 17 patients who had SPTs or IDTs with delayed readings was positive but considered irrelevant. One out of 32 patients who had a DPT had a mild reaction. DPTs were used only to confirm the current tolerance of needed medications and not for proof of responsibility of a highly suspected drug.

“Skin tests, while of limited sensitivity, can be helpful for considering the reintroduction of essential drugs according to a benefit-to-risk decision,” the authors concluded. “We propose an algorithm for approaching hypersensitivity testing in patients with EN, to be adapted to each patient.”

Reference
Roux C, Ben Said B, Milpied B, et al. Skin testing and drug provocation tests in epidermal necrolysis: a French experience. J Allergy Clin Immunol Pract. 2022;S2213-2198(22)00707-3. doi: 10.1016/j.jaip.2022.07.008. Epub ahead of print. PMID: 35870724.