Patch Testing With Methylchloroisothiazolinone/Methylisothiazolinone Using a New Diagnostic Mix-A Multicenter Study From the International Contact Dermatitis Research Group.

Abstract

BACKGROUND:

In the early 1980s, a preservative containing a mixture of methylchloroisothiazolinone (MCI) and methylisothiazolinone (MI) in a ratio of 3:1 was introduced. This mixture (mix) has been patch tested at 100 ppm (0.01%) worldwide and at 200 ppm (0.02%) in Sweden since 1986 and also in the European baseline series since 2014.

OBJECTIVE:

A new aqueous mix of MCI 0.015% and MI 0.2% was compared with patch testing with the 2 aqueous baseline preparations of MCI/MI 0.02% and MI 0.2%.

METHODS:

Four thousand three hundred ninety-seven patients with dermatitis in 12 International Contact Dermatitis Research Group dermatology departments from 3 continents were patch tested simultaneously with the 3 preparations.

RESULTS:

The frequency of positive patch tests to the allergens varied between 0% and 26.7% in the 12 test centers. The new mixture MCI/MI 0.215% in aqua (aq) detected significantly more patients with MCI/MI allergy than both MCI/MI 0.02% aq (P < 0.001) and MI 0.2% aq (P < 0.001) alone and combined.

CONCLUSIONS:

The results favor replacing the preparations MCI/MI 0.02% aq and MI 0.2% aq with the mixture MCI/MI 0.215% aq in the International Contact Dermatitis Research Group baseline series.

• Authors: Marléne Isaksson, Klaus E Andersen, Peter Elsner, Chee-Leok Goh, Margarida Gonçalo, An Goossens, Suzana Ljubojevic Hadzavdic, Melanie Pratt, Pailin Puangpet, Denis Sasseville, Kaushal Verma, Magnus Bruze
• Journal: Dermatitis : contact, atopic, occupational, drug (Dermatitis) 2021 Jul-Aug 01 Vol. 32 Issue 4 Pg. 220-224 ISSN: 2162-5220 [Electronic] United States
• PMID: 33405484 (Publication Type: Journal Article, Multicenter Study)
• Copyright: Copyright © 2021 American Contact Dermatitis Society. All Rights Reserved.

Chemical References

• Thiazoles
• 2-methyl-4-isothiazolin-3-one
• 5-chloro-2-methyl-4-isothiazolin-3-one

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Child
• Child, Preschool
• Dermatitis, Contact (diagnosis)
• Female
• Humans
• Infant
• Internationality
• Male
• Middle Aged
• Patch Tests (methods)
• Sweden
• Thiazoles (administration & dosage)
• Young Adult