[Monosystemic, oligolesional Langerhans cell histiocytosis. A rare congenital dermatosis].

A five-day-old female infant presented with congenital red-livid papules and nodules on the head, chest, back and left arm. The nodule on the chest was ulcerated at birth. The pregnancy and delivery were uneventful. There was no history of birth trauma to account for the ulcerated lesion. The parents and the three older siblings were healthy without similar skin lesions. The skin biopsy showed in the deep layer of the dermis a multinodular, granulomatous histiocytic infiltrate. The histiocytic cells expressed S-100 and CD1a. There were additionally many eosinophils. The suspected diagnosis Langerhans cell histiocytosis was confirmed by the histologic results. The patient was referred to pediatric hematology-oncology where evaluation showed no evidence of systemic involvement. The clinical, radiological, sonographic and histological results led to the diagnosis of a congenital, monosystemic, oligolesional Langerhans cell histiocytosis of the skin. In addition to the case presentation, we review the current stand of knowledge of the pathogenesis, the clinical classification and the therapy of the Langerhans cell histiocytosis.