Article Text
Abstract
Background Allopurinol is the most used urate-lowering agent for patients with gout. However, 10% of patients show intolerance to this drug, often at skin, which can be severe. Febuxostat is a novel non-purine selective xanthine oxidase inhibitor that has been proposed for allopurinol-intolerant patients due to its different structure. However, data regarding safety in those with previous skin reactions to allopurinol is still limited (1,2).
Objectives To assess the cutaneous safety of febuxostat when used in patients with previous skin reactions to allopurinol.
Methods Retrospective review of patients with crystal-proven gout treated with febuxostat in our Unit until December 2015. Those with previous skin reaction to allopurinol were selected. We registered epidemiological (age, gender), clinical (skin events) and laboratory variables (serum uric acid, glomerular filtration rate). The primary study variable was the rate of patients also presenting skin reactions with febuxostat. A descriptive analysis with estimation of the 95% confidence interval (95%CI) was performed.
Results Out 102 gout patients treated with febuxostat in our Unit, we identified 24 patients with prior allopurinol-related skin events. The median age was 68.5 years (p25-p75 53.7–71.0), being 18 males (75%). Most used starting dose of febuxostat was 80mg/d (n=16), others were 5mg/d (n=1), 40mg/d (n=4) or 120mg/d (n=3). Median glomerular filtration rate at that time was 77.2 mL/min (62.7–68.6). We have identified five patients (20.8%; 95%CI 3–38%) who also developed skin reactions with febuxostat (see table): in four cases a nonspecific rash, but one suffered from a Stevens-Johnson syndrome. None of these patients presented skin reactions to benzbromarone.
Conclusions In our series, one out five patients with previous skin reaction to allopurinol also developed after febuxostat. Larger studies are needed to confirm these results, but this finding strengths caution when using febuxostat in this subgroup of patients.
J Rheumatol 2011;38;1957.
Joint Bone Spine 2015 Dec 18.
Disclosure of Interest None declared