[Xanthogranuloma and cutaneous mastocytosis in adults].

Xanthogranuloma (XG) is a rare disease in adults. The authors report a case of XG in an 20 years-old woman. This observation is particularly interesting: First by the pathology of the cutaneous lesion which showed a dermal infiltrate composed of histiocytes and a few foamy cells but without Touton giant cells. Second by is association with a mastocytosis which disappeared when XG appeared. These data led the authors to discuss the misleading histology pattern of XG and also the pathogenesis of XG. In our case, it would appeared as a benign reactive process against mastocytosis.