RT Journal Article T1 [Langerhans cell histiocytosis with atypical and early neonatal debut]. T2 Histiocitosis de células de Langerhans con debut neonatal atipico y precoz. A1 García-Rodríguez, Esther A1 Bernabeu-Wittel, José A1 Calderón-López, Gemma A1 Pavón-Delgado, Antonio K1 Immunohistochemistry K1 Langerhans cell histiocytosis K1 Leukocytosis K1 Newborn AB Langerhans cell histiocytosis is a systemic disease associated with the proliferation of this type of cells in tissues. Its prevalence is estimated at 1-9/100 000. Bone is the most frequently affected organ, followed by the skin, lymph nodes, haematopoietic system, pituitary gland, lungs and liver. In the majority of cases, onset occurs during childhood, with peak between one and three years of age, and poor prognosis before two years of age. The haematological forms (pancytopenia) are usually aggressive in infants. We report a case of Langerhans cell histiocytosis with neonatal onset and complex diagnosis: maintained and significant leukocytosis was the predominant data for the first two months of life, so some type of leukemia was considered. However, the most common blood disorder in Langerhans cell histiocytosis is pancytopenia rather than leukocytosis, so that the diagnosis was delayed. YR 2016 FD 2016-04-01 LK http://hdl.handle.net/10668/9996 UL http://hdl.handle.net/10668/9996 LA es DS RISalud RD Apr 4, 2025