[Acute febrile neutrophilic dermatosis (Sweet syndrome). Phototherapy of persistent, postlesional erythemas].

We report a 31-year-old male patient suffering from Sweet's syndrome. The particularities of the case are the long period between onset of the disease and establishment of the diagnosis-the cutaneous lesions having persisted all the time, and the marked persistence of postlesional erythemas showing positive improvement by means of selective ultraviolet phototherapy (SUP).