Patch Testing With Carbamazepine: Reinduction of an Exfoliative Dermatitis

To the Editor.— The value of patch tests in the diagnosis of eruptions due to usage of carbamazepine has been emphasized in the medical literature.1-3Patch testing is a simple, reliable method, with few false-positive results, and only induces negligible side effects when correctly performed.4Nevertheless, we have recently seen an exfoliative dermatitis in a patient after a patch test with carbamazepine. Report of a Case.— A 16-year-old girl who had a history of epilepsy and depressive personality disorder was admitted to the hospital with a generalized erythematous dermatitis. The dermatitis started about one month after the beginning of carbamazepine therapy. The initial daily dose of carbamazepine was 100 mg/d, and it was increased to 300 mg/d after 20 days. There was no other local or general treatment. Two weeks after the dose was increased, the patient became weak, had a temperature of 39°C, and a few erythematous,