Background:
Because patients with atopic dermatitis are less prone to type IV allergies, there has been controversy regarding the role of patch testing in these patients.
Objective:
The present study was conducted to evaluate the role of patch testing in atopic individuals.
Methods:
One-hundred patients with hand eczema were patch tested using the standard patch test battery (HERMAL, Kurt Herrmann, Reinbek, West Germany) and the Finn chamber units. The total immunoglobulin class E (IgE) level was determined and correlated to the results of patch testing.
Results:
Eighty-seven patients had positive patch test reactions. Among the 87 patients, 39 (44.8%) had atopic dermatitis. The most common allergens yielding positive results were nickel sulfate, 2.5%, (58.6%); potassium dichromate, 0.25% (56.3%); carba mix, 3%, (44.82%); formaldehyde, 1% in H20, (40.22%); neomycin sulfate, 20%, (33.3%); and balsam of Peru 25%, (17.24%) respectively. Patients with atopic dermatitis were more frequently sensitive to neomycin sulfate than nonatopics.
Conclusion:
Patients with atopic dermatitis should be patch tested when indicated because they also develop contact allergic sensitization to a significant degree. Our observations indicate that patch testing with standard allergens often adds valuable information about contact sensitivity in these patients.