Scratch-chamber tests in food handler dermatitis.

Area of Science:

• Dermatology
• Allergology
• Occupational Health

Background:

• Hand dermatitis is common, particularly among food handlers.
• Identifying specific allergens contributing to hand dermatitis can be challenging.
• Distinguishing between allergic and irritant reactions is crucial for effective management.

Purpose of the Study:

• To investigate the role of food allergies in hand dermatitis.
• To evaluate the diagnostic accuracy of scratch-chamber and open application tests for food allergens.
• To identify specific foods and allergens associated with hand dermatitis in patients, including food handlers.

Main Methods:

• 80 patients with hand dermatitis underwent scratch-chamber and open application testing for various foods.
• Patients' occupational status (food handlers) and existing allergies (e.g., birch pollen, balsam of Peru) were recorded.
• Both immediate and delayed hypersensitivity reactions were assessed.

Main Results:

• Vegetables and spices commonly triggered immediate reactions, particularly in patients with birch pollen allergy.
• Spices, onion, and leek were associated with delayed reactions, especially in those allergic to balsam of Peru.
• Open application tests confirmed reactions in approximately 75% of patients with positive scratch-chamber tests.
• Clinically relevant reactions were observed with vegetables, fish, meat (immediate), and orange/lemon peel, onion (delayed).

Conclusions:

• Food allergies, particularly to vegetables, spices, and fruits, can contribute to hand dermatitis.
• Irritant factors like wet work and detergents are often the primary cause of hand dermatitis in food handlers, with food allergies playing a secondary role.
• Accurate diagnosis requires careful consideration of both allergic and irritant triggers, alongside patient history and specific testing.