Pure cutaneous relapsing langerhans cell histiocytosis in an adult

The histiocytic syndromes represent a group of rare diseases characterized by the proliferation of the mononuclear phagocyte system cells. We report a case of recurrent class I histiocytosis with exclusive cutaneous localization in an adult. Our patient had a 3 cm ulcerated nodule located on the right cheek. Subsequently, new lesions appeared, all having the same clinical evolution characterized by spontaneous resolution with scarring. After a five year follow up no more lesions were observed. The histopathological examination, immunohistochemical profile and electron microscopy of the lesions indicated Langerhans cell histiocytosis.