title: Cutaneous Langerhans cell histiocytosis in children under one year.
abstract: BACKGROUND
  To evaluate the clinical course and outcome of infants with Langerhans cell histiocytosis (LCH) involving skin and to estimate the incidence of progression to multi-system (M-S) disease in those with isolated skin involvement.
  
  
  METHODS
  A retrospective review was conducted on 22 LCH patients who were younger than 12 months at the onset of their skin eruption.
  
  
  RESULTS
  Twelve patients had isolated skin involvement at diagnosis and 10 were evaluable for progression. Four of the 10 (40%) evaluable patients progressed to multi-system (M-S) disease. Of the 10 patients with M-S disease at diagnosis, 5 had a history of a preceding skin eruption 2 to 13 months prior to diagnosis. Eleven of the 14 (79%) patients with M-S disease had risk organ involvement. The mortality rate of M-S disease was 50%.
  
  
  CONCLUSIONS
  It is important for primary caregivers to recognize that isolated cutaneous LCH in infants is not always a benign disorder. The diagnosis of self-healing cutaneous LCH should only be made in retrospect. Careful, albeit non-invasive, follow-up is recommended to monitor for disease progression and development of long-term complications.
authors.affiliation: Division of Haematology/Oncology, Department of Paediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Loretta
authors.initials: L
authors.lastname: Lau
authors.forename: Bernice
authors.initials: B
authors.lastname: Krafchik
authors.forename: Monika M
authors.initials: MM
authors.lastname: Trebo
authors.forename: Sheila
authors.initials: S
authors.lastname: Weitzman
mesh_terms: D018450:Disease Progression; D005260:Female; D006646:Histiocytosis, Langerhans-Cell / Q000188:drug therapy / Q000401:mortality / Q000473:pathology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009864:Ontario / Q000453:epidemiology; D012189:Retrospective Studies; D012871:Skin Diseases / Q000188:drug therapy / Q000401:mortality / Q000473:pathology; D015996:Survival Rate