Histological and clinical forms of the eosinophilic cellulitis (Wells' syndrome).

Background. Wells' syndrome is characterized by clinical features of cellul itis and a histological picture of eosinophilic infiltrate of the dermis wi th some "flame" figures. Patients and methods. The clinical and histological features of nine patien ts with Wells' syndrome seen from 1988 to 1998 were retrospectively reviewe d. Results. The clinical features of the ni ne patients (five men and four wom en) were urticaria (n = 1), cellulitis (n = 2), annular plaques (n = 3), ve siculo-bullous lesions (n = 2) and edema of the face with nodules of the co njunctiva (n = 1). Histological examination of skin biopsies showed an eosi nophilic infiltrate of the dermis associated with some "flame" figures in a ll cases. The infiltrate was located in the superficial or deep dermis in a ccordance with the different clinical features. One patient developed a non Hodgkin lymphoma and presented successively: a Wells' syndrome, a leucocyt oklastic vasculitis and a Sweet's syndrome. Numerous treatment were used: t opical corticosteroids, H1-antihistamines, dapsone and systemic corticoster oids. Two patients relapsed after treatment withdrawal. Discussion. This study demonstrated a wide polymorphism of the clinical and histological features of Wells' syndrome. The clinical features seem to de pend on the location of the dermal infiltrate, suggesting the existence of a spectrum of eosinophilic dermatoses, like in neutrophilic dermatoses. The successive occurrence of vasculitis, Wells' syndrome and Sweet' syndrome i n a patient suggests an overlap between these diseases. Systemic corticoste roids are the most effective treatment, but may lead to a corticosteroid de pendence.