Drug Reaction With Eosinophilia and Systemic Symptoms Induced by Valproic Acid: A Case Report

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a rare but life-threatening reaction to drugs such as carbamazepine and allopurinol. The condition is characterized by skin rashes, fever, hematological disturbances, lymphadenopathy, and organ failure, most probably hepatic dysfunction. To date, only a few cases of valproate-induced DRESS syndrome have been reported.
We report on the case of a 60-year-old man who had been treated with valproic acid some time before being referred to Kowsar Hospital, Semnan, Iran in December 2015. He was given valproic acid 1000 mg PO, and after 20 days, he had developed widespread rashes, fever, esophagitis, cervical lymphadenopathy, and tender hepatomegaly. Laboratory results at Kowsar showed a drop in hemoglobin, in addition to lymphocytosis, thrombocytopenia, and elevated serum transaminases. DRESS was diagnosed, and corticosteroid therapy was initiated. Administration of the culprit drug to the patient was also stopped. Intravenous immunoglobulin (IVIG) improved the general condition of the patient.
Only a small number of case reports have described valproic acid-induced DRESS syndrome; therefore, the condition is difficult to prevent. Rechallenge with valproic acid should be avoided in patients with a history of reaction to the drug..