Efficacy of anti-interleukin-1 receptor antagonist anakinra (Kineret®) in a case of refractory Sweet's syndrome.

Sweet's syndrome is a neutrophilic dermatosis characterized by fever, an elevated neutrophil count, and painful erythematous cutaneous lesions. Histopathological analysis reveals a neutrophilic dermal infiltrate. Systemic corticosteroid therapy remains the mainstay of treatment. We report the case of a 66-year-old male patient who had a 5-year history of Sweet's syndrome refractory to various conventional treatments. Anti-interleukin-1 receptor antagonist anakinra was initiated and this resulted in a dramatic clinical and biological improvement. Anakinra is a promising treatment for neutrophilic dermatoses and sheds light on the interleukin-1/inflammasome pathway as central in the physiopathology of neutrophilic dermatosis.