Severe Cutaneous Adverse Reactions (SCAR) of allopurinol and the important role of genetic tests in allopurinol-treated patients

Abstract

In general, Severe Cutaneous Adverse Reactions (SCAR) are rare but deadly adverse reactions including Steven-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN) or drug rash with eosinophilia and systemic syndrome (DRESS). As a classic anti-hyperuricemia drug, allopurinol is one of  the top SCAR-inducing drugs. Notably, SCAR dangers for allopurinol users are the highest for patients of Asian origins. This review aims to analyze risk factors and the role of genetic tests for minimization of allopurinol-induced SCAR’s. Carrying the popymorphic HLA-B*5801 allele appears the most important risk factor of allopurinol-induced SCAR’s, followed by renal impairment, and female gender is more sensitive. Many pharmacogenetic studies and cost/effectiveness studies showed that the genetic test of HLA-B*5801 is helpful for stratifying patients and thereby minimizing SCAR dangers in allopurinol users.