Allopurinol: Attention to the Prescription!

Abstract

Allopurinol is a commun hypo-uricemic drug. However, it is main drug reported to be inducing toxidermy. Our goal is to encourage limiting the prescription of this drug and to reserve it for justified cases after some observations. A Retrospective study was conducted in the Dermatology department between 2012 and 2019. We collected all toxidermy cases following Allopurinol. During the study period,39 cases of severe Allopurinol toxidermia, including 22 women and 17 men, a sex ratio of 0.77. The average age was 65 years old. Most of the patients were "poly-medicated". The average time between medication and clinical symptoms was 28.25 days. Clinical manifestations were: macula-papular rash in 12 cases (30%), erythroderma in 14 cases (35%), purpura in 7 cases (17%) and mucosal involvement in 20 cases. Fever in 29 cases, a state of shock in 5 cases. 10 patients required a transfer in intensive care. On the balance sheet; eosinophilia was found in 23 cases, 18 cases of hepatic cytolysis, CPK mb was elevated in 17 cases, acute renal failure in 24 cases. The biopsy was performed in all cases confirming the toxidermy. The Drug reaction eosinophilia and systemic symptoms (DRESS) retained in 29 cases, Stevens-Johnson syndrome (SJS) in 2 cases, Lyell in 4 cases. The management involved stopping the incriminated drug (Allopurinol) and the introduction of an antihistamine and an emollient were prescribed in all patients. Topical steroid in 21 patients. Oral corticosteroid therapy in 14 patients. A bolus of corticosteroid was administered in 4 patients. The evolution was good for 30 patients (77%). However, we recorded 9 deaths in a context of septic shock and multi-visceral failure. In our series, Allopurinol was the cause of severe toxidermia including Lyell syndrome, StevensJohnson and DRESS syndrome. The severity of these diseases should encourage preserving it for the justified cases, and knowing how to adapt the dosage to the renal function, to introduce the treatment in a progressive way and to stop the treatment in case of less signs of toxidermy. The control of the use of this molecule would reduce the cases of this disease.