Sensitization and cross-reaction patterns in Danish Compositae-allergic patients

Area of Science:

• Dermatology
• Allergology
• Plant Science

Background:

• Compositae-allergic contact dermatitis is common, often triggered by sesquiterpene lactones (SL) and Compositae mix (CM).
• Identifying specific allergens is crucial for accurate diagnosis and management.

Purpose of the Study:

• To present results of aimed patch testing in Compositae-allergic patients.
• To identify the most frequent elicitors of allergic reactions from SL and CM constituents.

Main Methods:

• Aimed patch testing was performed on 190 Compositae-allergic patients over 8 years.
• Testing included constituents of SL mix, CM, and other Compositae extracts.

Main Results:

• Feverfew (CM) and dehydrocostus lactone (SL) were the most frequent positive reactors.
• Chrysanthemum and marguerite were key sensitizers in both occupational and non-occupational groups.
• Cross-reactions between chrysanthemum and other Compositae plants were observed.
• Garden plants like feverfew and blanket flower were significant in non-occupationally exposed individuals.
• Lettuce-allergic individuals were often CM-positive.
• 19% of occupationally sensitized patients were negative to both SL and CM, necessitating broader testing.

Conclusions:

• Targeted patch testing with SL and CM constituents is effective in identifying Compositae allergens.
• Feverfew, dehydrocostus lactone, chrysanthemum, and marguerite are important allergens.
• Cross-reactivity influences sensitization patterns.
• Specific allergens like Gerbera and Osteospermum may require specialized testing.