ORIGINAL ARTICLE Clinical Profile of Langerhans Cell Histiocytosis at a Tertiary Centre: A Prospective Study Preena Uppal & Meenakshi Bothra & Rachna Seth & Venkat Iyer & Sushil Kumar Kabra Received: 28 June 2011 / Accepted: 9 February 2012 / Published online: 6 March 2012 # Dr. K C Chaudhuri Foundation 2012 Abstract Objective To study the varied presentations of Langerhans Cell Histiocytosis (LCH), the differential diagnosis of the varied presentations and the time lag in achieving the diag- nosis. Prospective analysis of children diagnosed to have LCH over a period of 51 mo was done. A complete history and physical examination was undertaken in all patients, followed by relevant laboratory and radiological evaluation. Biopsy of the appropriate specimen was done. The extent of the disease was documented, accordingly treated and followed up. Results There were 16 children with LCH from October 2005 through December 2009. The age ranged from 8 mo to 72 mo. Diagnosis was confirmed by CD1a/S 100 in 15 children (93.75%). The mean time to arrive at the diag- nosis was 9.9 mo. Multisystem disease was documented in 11 (68.75%) children and there were 4 (25.0%) cases of pulmonary LCH. The mean time of follow-up was 14.4 mo (range, 1 mo to 50.6 mo). Most common referral diagnoses in LCH patients was recurrent pneumonia and immunodeficiency. Conclusions There is a need for high index of suspicion for diagnosis of LCH; misdiagnosis is frequent. Pulmonary involvement in children with LCH appears common. It is possibly still underdiagnosed. Nail changes are uncommon, but may act as a marker for multisystem disease. In addition to survival data and analysis of prognostic factors, the prospective collection of data on diverse presentations is essential, along with a high index of suspicion for the diagnosis of LCH. Keywords Langerhans cell histiocytosis . Childhood . Clinical profile . Pulmonary histiocytosis . Misdiagnosis Introduction Langerhans’ cell histiocytosis (LCH), characterized by clon- al proliferation of pathologic cells with the characteristics of Langerhans cells (LCs) is often diagnosed late because it mimics many diseases [1]. The clinical manifestations vary from spontaneously resolving lesions to a progressive multisystem disorder with organ dysfunction and life threat- ening complications [1–3]. Intermediate forms, character- ized by lesions of bone, skin and mucous membranes, various degrees of organ dysfunction and diabetes insipidus have an indolent course. These signs and symptoms have long been attributed to various unrelated diseases. LCH was diagnosed as an individual entity only in the later half of the twentieth century [4]. The presentation of LCH also varies with age. The peak onset of LCH is between 1 and 4 y, although it can occur in any age [5]. Varied clinical presentations result in misdiagno- sis and a consequent delay to reach the final diagnosis. The diagnosis of LCH essentially rests on demonstration of typical histological features supplemented by immunophenotypic markers in various tissues and body fluids. Also, there is wide variability in diagnostic and therapeutic protocols. Various large retrospective studies have been done to analyze the prognostic factors, disease-distribution and P. Uppal : M. Bothra : R. Seth (*) : S. K. Kabra Department of Pediatrics, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India e-mail: drrachnaseth@yahoo.co.in V. Iyer Department of Pathology, All India Institute of Medical Sciences, New Delhi, India Indian J Pediatr (November 2012) 79(11):1463–1467 DOI 10.1007/s12098-012-0719-7