title: Swelling of bilateral parotid glands: An unusual symptom of multisystem Langerhans cell histiocytosis.
abstract: OBJECTIVE
  Langerhans cell histiocytosis is an unusual disorder of unknown etiology with heterogeneous clinical behaviors and variable outcomes. It can involve one or more organs or systems, but to our best knowledge, parotid glands involvement in Langerhans cell histiocytosis is extremely rare in English literature.
  
  
  METHODS
  We report a 13-month-old girl who presented with bilateral parotid swelling as presenting symptom. She was misdiagnosed for 4 months, but final diagnosis was multisystem Langerhans cell histiocytosis.
  
  
  RESULTS
  After being treated for 18 months, the patient acquired complete remission and attained similar growth status to other healthy children.
  
  
  CONCLUSIONS
  Langerhans cell histiocytosis may involve any organ; in patients with parotid enlargement, Langerhans cell histiocytosis should be kept in mind in the differential diagnoses. We emphasize the importance of biopsy for histologic evaluation as soon as possible and even repeatedly if initial results are negative for Langerhans cell histiocytosis.
authors.affiliation: Department of Pediatric Hematology/Oncology, Xin Hua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Yuan
authors.affiliation: Department of Pediatric Hematology/Oncology, Xin Hua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Mengjie
authors.initials: M
authors.lastname: Tang
authors.affiliation: Department of Pediatric Hematology/Oncology, Xin Hua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Sheng
authors.affiliation: Pediatric Intensive Care Unit, Xin Hua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Department of Pediatric Hematology/Oncology, Xin Hua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Zhang
keywords: Langerhans cell histiocytosis; differential diagnosis; parotid gland; pediatric