Epicutaneous patch testing in drug hypersensitivity syndrome (DRESS)

Abstract

Background: In some patterns of cutaneous adverse drug reactions, and depending on the culprit drug, patch testing has been helpful in confirming its cause. Its value in Drug Rash with Eosinophilia and Systemic Symptoms (DRESS) has not been established in a large cohort of patients. Objective: The aim of the present study is to evaluate the safety and usefulness of patch testing in DRESS. Patients/Methods: Between January 1998 and December 2008, we studied 56 patients with DRESS induced by antiepileptic agents in 33 patients (59%), allopurinol in 19 (34%) and sulfasalazine, cotrimoxazole, tenoxicam, and amoxicillin in 1 patient each (7%). Results: A positive patch test reaction was observed in 18 patients (32.1%), of which 17 were with antiepileptics and 1 with tenoxicam. In the antiepileptic group, carbamazepine alone was responsible for 13 of 17 positive reactions (76.5%). Patch tests with allopurinol and its metabolite were negative in all cases attributed to this drug. Conclusions: In this study, patch testing was a safe and useful method in confirming the culprit drug in DRESS induced by antiepileptic drugs, whereas it had no value in DRESS induced by allopurinol. The pathogenesis of DRESS is not yet entirely clarified, but positive patch tests suggest a drug‐dependent delayed hypersensitivity mechanism.

HLA-B*58:01is a risk factor for allopurinol-induced DRESS and Stevens-Johnson syndrome/toxic epidermal necrolysis in a Portuguese population

“…and both substances at 1% and 10% in ethanol and acetone. 31 Additionally, we studied a group of six patients (three male/three female), aged 49-86 years (mean 70Á3), hospitalized for an MPE induced by allopurinol, with minor systemic symptoms, who did not fulfil the criteria for DRESS.…”

Phenytoin Induced Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)

“…Intravenous immunoglobulin (IVIG) and/or plasmapheresis can be done in case of further progression of disease. Recovery is usually slow and may take weeks to months 9 .…”

Reações Cutâneas de Hipersensibilidade Retardada a Medicamentos: Serão os Testes Epicutâneos Positivos Persistentes?

“…4 O mesmo é válido para a carbamazepina, no caso dos anticonvulsivantes. 7 Estes doentes foram posteriormente entrevistados telefonicamente acerca de nova exposição aos fármacos imputá-veis com possível RAMc (após os testes epicutâneos iniciais). Naqueles em que tal exposição não ocorreu foi proposta a repetição dos testes epicutâneos, pelo menos 2 anos após a realização dos primeiros testes.…”

“…[1][2][3] Os testes epicutâneos têm-se revelado úteis no estudo destas RAMc retardadas, tanto a antibióticos, como a anticonvulsivantes, com alta especificidade mas uma sensibilidade variável em função do fármaco imputável e do tipo de erupção medicamentosa. [4][5][6][7] De acordo com as recomendações atuais para o estudo das RAMc retardadas, os testes epicutâneos devem ser realizados entre 3-6 semanas até 3-6 meses após a resolução da erupção cutânea. 8,9 No entanto, testes epicutâneos positivos foram pontualmente observados, pela primeira, vez vários anos ou décadas após a erupção cutânea inicial.…”