Patch testing with formaldehyde and formaldehyde-releasers: multicentre study in Spain (2005-2009).

Area of Science:

• Dermatology
• Allergology
• Toxicology

Background:

• Formaldehyde and formaldehyde-releasers are frequent causes of allergic contact dermatitis.
• Understanding sensitization patterns is crucial for diagnosis and management.

Purpose of the Study:

• Determine the frequency of sensitization to formaldehyde and seven formaldehyde-releasers.
• Characterize patient groups based on patch test results.

Main Methods:

• A 5-year retrospective study was conducted in six Spanish hospitals.
• Patients with positive patch tests to formaldehyde or formaldehyde-releasers were analyzed.

Main Results:

• Formaldehyde (1.72%), imidazolidinyl urea (1.05%), quaternium-15 (0.88%), and diazolidinyl urea (0.79%) were the most common allergens.
• Occupational dermatitis was more frequent in patients sensitized only to formaldehyde (25%) versus formaldehyde-releasers (9.5%).
• Hand dermatitis was common in formaldehyde-only sensitization, while face and leg dermatitis were noted in formaldehyde-releaser sensitization.

Conclusions:

• Imidazolidinyl urea and diazolidinyl urea are significant sensitizers.
• Including these in baseline patch test series can improve classification of formaldehyde-allergic patients.
• Enhanced classification can aid in managing allergic contact dermatitis.