[Sézary's syndrome (author's transl)].

The syndrome described in 1938 by Sézary and Bouvrain is characterized by a possibly hyperpigmented erythroderma with oedema and infiltration of the skin, palmo-plantar keratoderma, diffuse alopecia and large lymphadenopathies. The cutaneous histopathology frequently shows a dermal mononuclear infiltrate with, sometimes, epidermal microabcesses. But none of these signs is actually specific for the Sézary syndrom, the only criteria of which is the presence of circulating Sézary cells with their folded, cerebriform nucleus demonstrated by electron microscopy. The Sezary cell is to date clearly identified as a T lymphocyte but membrane markers and Tcell fonction studies could elicite abnormal and poor reactive T cell. In order to assert the Sézary Syndrome it is stated by the authors that the erythroderma must be associated with more than 10% of Sézary cells in peripheral blood. This feature is needed to differentiate the Sézary syndrome from the erythrodermic form of mycosis fondoïdes in which the abnormal T cell proliferation is mainly located in the skin. The relationship with the T cell chronic lymphatic leukemia and the main treatments of the Sezary syndrome are discussed.