title: An epidemiologic case-control study in a population with vitiligo.
abstract: BACKGROUND
  Previous epidemiologic studies of vitiligo have not included a sex- and age-matched population.
  
  
  OBJECTIVE
  Our purpose was to attempt to determine possible risk factors and clinical differences associated with unilateral and bilateral vitiligo.
  
  
  METHODS
  Two hundred thirty-four patients and 234 normal control subjects were examined and questioned.
  
  
  RESULTS
  Patients with unilateral vitiligo were younger and had an earlier age at onset. Koebner's phenomenon and halo nevus were infrequent in the total vitiligo group, but no difference between vitiligo types was observed. Subjects with bilateral vitiligo more frequently had light skin (types I, II, and III) and more commonly had an associated autoimmune disease.
  
  
  CONCLUSIONS
  Unilateral and bilateral vitiligo differ substantially in several clinical aspects, which suggests a different pathogenic mechanism for each condition.
authors.affiliation: Department of Internal Medicine, Universidad del Valle, Cali, Colombia.
authors.forename: M I
authors.initials: MI
authors.lastname: Barona
authors.forename: A
authors.initials: A
authors.lastname: Arrunátegui
authors.forename: R
authors.initials: R
authors.lastname: Falabella
authors.forename: A
authors.initials: A
authors.lastname: Alzate
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D001327:Autoimmune Diseases / Q000453:epidemiology / Q000235:genetics; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D009508:Nevus, Pigmented / Q000453:epidemiology; D012307:Risk Factors; D012737:Sex Factors; D012867:Skin / Q000473:pathology; D012878:Skin Neoplasms / Q000453:epidemiology; D012880:Skin Pigmentation; D014820:Vitiligo / Q000453:epidemiology* / Q000235:genetics / Q000473:pathology