Langerhans cell histiocytosis masquerading as acute appendicitis: Case report and review

Langerhans cell histiocytosis(LCH) is a rare syndrome characterized by unifocal,multifocal unisystem,or disseminated/multi-system disease that commonly involves the bone,skin,lymph nodes,pituitary,or sometimes lung(almost exclusively in smokers) causing a variety of symptoms from rashes and bone lesions to diabetes insipidus or pulmonary infiltrates.We present a previously unreported case of gastrointestinal LCH as well as a novel characteristic lesion affecting the colon of a young woman who presented with signs and symptoms mimicking acute on chronic appendicitis.Immunohistochemical analysis of appendectomy specimen and nodular specimens on colonoscopy demonstrated S-100,CD1a,and langerin reactivity.The patient underwent systemic chemotherapy with cytarabine and demonstrated excellent response to therapy.