title: Lichen planopilaris after hair transplantation: report of 17 cases.
abstract: BACKGROUND
  Lichen planopilaris (LPP) is a type of primary scarring alopecia. The pathogenesis is poorly understood, although traumatic skin injury has been implicated in some cases.
  
  
  OBJECTIVE
  To present 17 patients diagnosed with LPP after hair transplant surgery.
  
  
  METHODS
  A retrospective review of the records of patients referred for evaluation of suboptimal growth after hair transplantation and diagnosed with LPP. Patients' scalps were evaluated using dermoscopy, and scalp biopsies were performed in all patients to confirm the diagnosis of LPP.
  
  
  CONCLUSIONS
  Seventeen patients (15 male, 2 female) were diagnosed with LPP after hair transplant surgery. The timing of disease occurrence was variable--4 to 36 months after hair transplantation. The most common symptom was itching. Perifollicular erythema or perifollicular scale, the classical dermatoscopic signs of LPP,was present in 12 patients (70%).
  
  
  CONCLUSIONS
  These data provide further support for an association between hair transplant surgery and the development of LPP. Traumatic skin injury from recipient site creation may be relevant to the pathogenesis. The incidence of this phenomenon and risk factors remain to be clarified.
authors.affiliation: Division of Dermatology, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario, Canada. jeffrey.donovan@utoronto.ca
authors.forename: Jeff
authors.initials: J
authors.lastname: Donovan
mesh_terms: D000328:Adult; D000368:Aged; D000505:Alopecia / Q000209:etiology* / Q000473:pathology; D046169:Dermoscopy; D005260:Female; D006197:Hair / Q000637:transplantation*; D006801:Humans; D008010:Lichen Planus / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D012536:Scalp Dermatoses / Q000209:etiology* / Q000473:pathology