Positive concomitant test reactions to allergens in the standard patch test series

Area of Science:

• Dermatology
• Immunology
• Allergology

Background:

• Patch testing is crucial for diagnosing allergic contact dermatitis.
• While allergen cross-reactivity is suspected, large-scale confirmations are limited.
• This study aimed to identify significant correlations in positive patch test reactions.

Purpose of the Study:

• To investigate significant correlations between positive patch test reactions.
• To confirm and identify cross-reacting allergens in a large patient cohort.
• To provide data supporting clinical management of allergic contact dermatitis.

Main Methods:

• Analysis of 1235 patients undergoing patch testing.
• Utilized the Hermal standard series at Massachusetts General Hospital.
• Data collected between 1990 and 2006.

Main Results:

• 33.3% of patients showed two or more positive reactions.
• Eight pairs of allergens demonstrated statistically significant correlations (P ≤ 0.0001).
• Confirmed cross-reactions include formaldehyde/releasers, balsam of Peru/fragrance mix, and potassium dichromate/colophony.

Conclusions:

• Clinicians must be aware of cross-reacting allergens for successful patient management.
• Understanding these correlations aids in resolving allergic dermatitis.
• This knowledge is essential for effective patient counseling.