title: Unifocal Langerhans cell histiocytosis presenting as an aggressive bone lesion.
abstract: OBJECTIVE
  To discuss a case of unifocal Langerhans cell histiocytosis (eosinophilic granuloma) presenting as an aggressive osseous destructive process.
  
  
  METHODS
  A 6-year-old girl had thigh pain of insidious onset that would wake her at night. Orthopedic testing reproduced local pain, and imaging revealed an osteolytic process in the femoral diaphysis with laminated periosteal reaction.
  
  
  RESULTS
  The patient was referred for further evaluation; unifocal Langerhans cell histiocytosis was found at biopsy and spontaneous healing subsequently reported.
  
  
  CONCLUSIONS
  Unifocal Langerhans cell histiocytosis may present with deceptive clinical and imaging findings, of which clinicians should be aware.
authors.affiliation: University of Glamorgan, Wales, UK. kjyoung@glam.ac.uk
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Young
authors.forename: Stephanie
authors.initials: S
authors.lastname: George
mesh_terms: D001847:Bone Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology*; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000473:pathology; D006646:Histiocytosis, Langerhans-Cell / Q000150:complications*; D006801:Humans; D008279:Magnetic Resonance Imaging; D011859:Radiography; D011877:Radionuclide Imaging