Firdous, SanaM, LavanyaSwarna, SriKumari, K Swarajya2020-01-022020-01-022019-11Firdous Sana, M Lavanya, Swarna Sri, Kumari K Swarajya. Langerhans Cell Histiocytosis - A Rare Case Diagnosed Cytologically. Annals of International medical and Dental Research. 2019 Nov; 5(6): 24-262395-28222395-2814http://imsear.searo.who.int/handle/123456789/189162LCH is a rare idiopathic disorder characterized by pathogenic clonal proliferation of bone marrow derived langerhans cells which are immature dendritic cells characterized by presence of Birbeck granules. The annual incidence of LCH is nearly 5.4cases per one million people with male predominance. LCH is primarily a pediatric disease with peak age ranging between 1-4 yrs commonly involving bone. It manifests as single system unifocal, multifocal or multisystem disease. The purpose of this case report is to describe a case of 10 month old male baby with unifocal bone involvement and discuss the clinical, radiological and characteristic cytological features that lead to the diagnosis of LCH.Langerhans cell histiocytosis (LCH)cytological featuresunifocal bony lesionJournal ArticleIndiaPost Graduate, Department of Pathology, Osmania Medical College, Hyderabad, IndiaAssistant Professor, Department of Pathology, Osmania Medical College, Hyderabad, IndiaAssociate Professor, Department of Pathology, Osmania Medical College, Hyderabad, India.