Letterer–Siwe disease: a case of multisystem Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH), previously known as histiocytosis X, is an idiopathic uncommon haematological condition affecting infants and young children but can occur at any age group characterized by clonal proliferation of abnormal Langerhans cells. Langerhans cells express an immunophenotype positive for S100 protein, CD1a and Langerin (CD207). Here we present a case of 2-year-old male patient presented with a multiple raw area associated with oozing, bleeding and crusted lesions were present over scalp, trunk and post-auricular areas. Radiographic examination revealed multiple osteolytic bone involvement. Histopathological examination revealed Langerhans cell histiocytosis. Immunophenotyping was positive for vimentin, CD1a, and S100. Based on radiological, histological and immunophenotyping findings suggestive of multisystem LCH. The purpose of this report is to describe a rare case of LCH in the 2-year-old male child with multisystem LCH involving skin, soft tissue and bones and to discuss clinical, radiological and histopathological features of LCH.