Prevalence of methylchloroisothiazolinone and methylisothiazolinone contact allergy in facial dermatitis: a single centre Irish study

J Eur Acad Dermatol Venereol. 2016 Jan;30(1):60-2. doi: 10.1111/jdv.12956. Epub 2015 Jan 26.

Abstract

Background: There has been an increase in methylchloroisothiazolinone (MCI) and especially methylisothiazolinone (MI) contact allergy in recent years.

Objectives: We examined the prevalence and demography of MCI/MI and MI contact allergy in patients presenting with facial dermatitis.

Methods: Eighty patients with facial dermatitis were patch tested to the British Society for Cutaneous Allergy standard series, preservatives and own products between January 2012 and March 2014.

Results: A total of 14 (17.5%) patients had positive reactions to this preservative. Five (6.3%) patients tested positive to MCI/MI (0.02%), four (5%) patients tested positive to MI (0.2%) and five (6.3%) patients tested positive to both preparations. Six (7.5%) of these patients were atopic. All patients were female and the mean age was 53.8 years. Sources of allergen were in cosmetics and skin care products.

Conclusions: Contact allergies to MCI/MI and MI are commoner than what was reported before and is an emerging cause of facial dermatitis. The detection rate of this allergen was increased by 5% in our cohort since the inclusion of MI (0.2%) in the standard series.

MeSH terms

  • Dermatitis, Allergic Contact / epidemiology
  • Dermatitis, Allergic Contact / etiology*
  • Face*
  • Female
  • Humans
  • Ireland / epidemiology
  • Middle Aged
  • Patch Tests
  • Preservatives, Pharmaceutical / adverse effects*
  • Prevalence
  • Retrospective Studies
  • Thiazoles / adverse effects*

Substances

  • Preservatives, Pharmaceutical
  • Thiazoles
  • 2-methyl-4-isothiazolin-3-one
  • 5-chloro-2-methyl-4-isothiazolin-3-one