title: Central diabetes insipidus as presenting symptom of Langerhans cell histiocytosis.
abstract: OBJECTIVE
  Central diabetes insipidus (CDI) is a rare disorder associated with various underlying diseases. Among the systemic diseases that may cause CDI, Langerhans cell histiocytosis (LCH) is the most common. Therefore, in patients with endocrinologically proven CDI, a comprehensive diagnostic evaluation is crucial to identify possible extracranial sites of LCH. The goal of the diagnostic evaluation is to yield histopathological proof of the underlying disease. If possible, this histopathological proof should be provided by a biopsy of extracranial lesions to avoid a potentially hazardous biopsy of the pituitary stalk.
  
  
  METHODS
  In this retrospective study we included 54 patients registered at the LCH study reference center in whom the onset of CDI preceded the diagnosis of LCH, and we investigated their presentation and course to define a clinical pattern characteristic for LCH.
  
  
  RESULTS
  In 49/54 patients (91%) the detection and biopsy of extracranial lesions led to the diagnosis of LCH. The most frequently involved organs were bones, skin, and lungs; 86% of the patients with bone lesions had skull lesions. In 18% of the patients extracranial lesions were already found at presentation of CDI, in another 51% of the patients extracranial lesions were found within 1 year from onset of CDI.
  
  
  CONCLUSIONS
  These observations underline that a comprehensive search for extracranial lesions at presentation and during the first year thereafter may help to achieve a specific diagnosis without a pituitary stalk biopsy.
authors.affiliation: Children's Cancer Research Institute, Vienna, Austria.
authors.forename: Helmut
authors.initials: H
authors.lastname: Prosch
authors.forename: Nicole
authors.initials: N
authors.lastname: Grois
authors.forename: Daniela
authors.initials: D
authors.lastname: Prayer
authors.forename: Franz
authors.initials: F
authors.lastname: Waldhauser
authors.forename: Manuel
authors.initials: M
authors.lastname: Steiner
authors.forename: Milen
authors.initials: M
authors.lastname: Minkov
authors.forename: Helmut
authors.initials: H
authors.lastname: Gadner
mesh_terms: D000293:Adolescent; D000328:Adult; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D020790:Diabetes Insipidus, Neurogenic / Q000175:diagnosis* / Q000209:etiology; D003937:Diagnosis, Differential; D005260:Female; D006646:Histiocytosis, Langerhans-Cell / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D007223:Infant; D008297:Male; D010902:Pituitary Gland / Q000473:pathology; D012189:Retrospective Studies