title: Allergic contact dermatitis to metal allergens in Iran.
abstract: BACKGROUND
  Metallic allergens such as nickel are among the most common causes of allergic contact dermatitis (ACD), but frequencies of contact dermatitis to these allergens may vary in different areas.
  
  
  OBJECTIVE
  This study aimed to determine the frequencies of ACD caused by three common metallic allergens: nickel sulfate; potassium dichromate; and cobalt chloride.
  
  
  METHODS
  Data for 1137 patients with clinical diagnoses of contact dermatitis and/or atopic dermatitis evaluated by patch testing in Iran during a 5-year period were retrospectively studied to establish the frequencies of hypersensitivity to these metallic allergens.
  
  
  RESULTS
  A total of 313 patients (27.5%) gave positive patch test results for at least one metallic allergen. Allergy to nickel (229 cases, 20.0%) was the most commonly observed, followed by allergy to cobalt (90 cases, 8.0%) and allergy to chromium (70 cases, 6.2%). Nickel allergy was significantly more frequent in females and in subjects aged <40 years, whereas chromium hypersensitivity was more common in males and in subjects aged >40 years. Sensitivity to nickel or chromium was a risk factor for cobalt allergy.
  
  
  CONCLUSIONS
  Nickel was most commonly identified as a metallic allergen in Iran and tended to affect women aged <40 years. Regulations pertaining to nickel release may decrease the frequency of nickel hypersensitivity in Iran.
authors.affiliation: Center for Research and Training in Skin Diseases and Leprosy, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Khatami
authors.forename: Mansour
authors.initials: M
authors.lastname: Nassiri-Kashani
authors.forename: Farzam
authors.initials: F
authors.lastname: Gorouhi
authors.forename: Shahab
authors.initials: S
authors.lastname: Babakoohi
authors.forename: Ali
authors.initials: A
authors.lastname: Kazerouni-Timsar
authors.forename: Parastoo
authors.initials: P
authors.lastname: Davari
authors.forename: Maryam
authors.initials: M
authors.lastname: Sarraf-Yazdy
authors.forename: Yahya
authors.initials: Y
authors.lastname: Dowlati
authors.forename: Alireza
authors.initials: A
authors.lastname: Firooz
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000485:Allergens / Q000009:adverse effects* / Q000276:immunology; D003035:Cobalt / Q000009:adverse effects / Q000276:immunology; D017449:Dermatitis, Allergic Contact / Q000453:epidemiology* / Q000276:immunology; D005260:Female; D006801:Humans; D007492:Iran / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008670:Metals / Q000009:adverse effects* / Q000276:immunology; D009532:Nickel / Q000009:adverse effects / Q000276:immunology; D011192:Potassium Dichromate / Q000009:adverse effects / Q000276:immunology; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult
chemical_list: D000485:Allergens; D008670:Metals; D003035:Cobalt; C029938:nickel sulfate; D009532:Nickel; C018021:cobaltous chloride; D011192:Potassium Dichromate