Related Experiment Video
Updated: Mar 8, 2026
An In Vitro Skin Irritation Test SIT using the EpiDerm Reconstructed Human Epidermal RHE Model
Published on: July 13, 2009
Appropriate Testing of Isothiazolinones in Children
Alina Goldenberg1, Michael Lipp2, Sharon E Jacob3
1Department of Dermatology, University of California at San Diego, San Diego, California.
Insights
Pediatric allergic contact dermatitis (ACD) due to methylisothiazolinone (MI) is often missed. Comprehensive patch testing, including MI alone, is crucial for accurate diagnosis in children with persistent dermatitis.
Area of Science:
- Dermatology
- Allergology
- Pediatrics
Background:
- Isothiazolinones, specifically methylchloroisothiazolinone (MCI) and methylisothiazolinone (MI), are common causes of allergic contact dermatitis (ACD) in children.
- Methylisothiazolinone (MI) associated ACD is frequently underreported in scientific literature.
Purpose of the Study:
- To determine the prevalence of positive patch tests (PPTs) for MCI/MI and MI alone in U.S. pediatric cases.
- To evaluate the diagnostic yield of different patch testing strategies for MI sensitization.
Main Methods:
- Utilized a database of provider-reported U.S. pediatric patch test cases from across all 50 states.
- Analyzed over 1100 logged cases for positive patch tests to MCI/MI combination and MI alone.
Main Results:
- Identified 96 cases with positive patch tests within one year; 37 reacted to MCI/MI (MI alone negative/not tested), and 39 reacted to MI alone.
- Comprehensive patch testing identified 51% more MI allergies than testing with MCI/MI alone.
- Only 3% of MI-alone sensitizations were detected with standard testing; 97% required comprehensive testing.
Conclusions:
- Accurate assessment of isothiazolinone sensitization requires specific testing for MI, in addition to MCI/MI.
- Patch testing for MI alone is recommended for children with persistent or recalcitrant dermatitis to identify underlying sensitization.
Background/Objective:
The isothiazolinones methylchloroisothiazolinone (MCI) and methylisothiazolinone (MI) are prevalent pediatric contact sensitizers. MI allergic contact dermatitis (ACD) is underreported in the literature. The objective of the current study was to use a database of provider-reported U.S. pediatric patch test cases to evaluate the positive patch test (PPT) prevalence rates of the combined preservative test substrate MCI/MI and of MI alone.
Methods:
U.S. pediatric patch test providers in all 50 states who had joined the registry were invited to submit deidentified cases to the database. More than 1100 logged cases in the database were evaluated for PPTs to MCI/MI combination, MCI/MI and MI, and MI alone.
Results:
Within 1 year of data collection, 96 cases with a PPT for MCI/MI, MCI/MI and MI, and MI alone were identified; 37 of these were positive to MCI/MI, with MI alone not tested or negative, and 39 were positive to MI only, with MCI/MI and MI tested. Fifteen (41%) of the MCI/MI cases were detected using an epicutaneous patch test alone and 22 cases (59%) using comprehensive patch testing. Only one case (3%) of MI alone sensitization was detected using T.R.U.E. plus a supplemental panel of tests; the remaining 38 cases (97%) were detected using comprehensive testing. Testing with only the combined MCI/MI preservative substrate may miss 51% of MI allergies.
Conclusion:
Appropriate testing of isothiazolinones is needed to clarify the true prevalence of sensitization to these allergens and the burden of pediatric ACD. Patch testing for MI alone in addition to MCI/MI combination is warranted in children with recalcitrant dermatitis.
More Related Videos
10:13Eye Irritation Test EIT for Hazard Identification of Eye Irritating Chemicals using Reconstructed Human Cornea-like Epithelial RhCE Tissue Model
Published on: August 23, 2015
09:02A Method to Test the Efficacy of Handwashing for the Removal of Emerging Infectious Pathogens
Published on: June 7, 2017
Related Concept Videos
01:23Toxicity Testing in Animals
01:29Drug Dosing: Infants and Children