Comparative Study of IQ-Ultra and Finn Chambers Test Methodologies in Detecting 10 Common Standard Allergens that Cause Allergic Contact Dermatitis

Background: Patch testing is routinely used in contact dermatitis clinics because it is the gold standard for the evaluation of potential allergic contact dermatitis. Objective: The study was undertaken to evaluate possible differences in reactivity between the Finn Chamber and IQ-Ultra patch-testing methodologies. Methods: Patients were patch-tested simultaneously with the Finn Chamber and IQ-Ultra patch tests. Ten standard allergens set by the North American Contact Dermatitis Group were used for both techniques. Results: Both patch tests had a significant agreement in detecting all of the allergens. An almost perfect agreement was noted for ethylenediamine dihydrochloride, quaternium-15, mercapto mix, black rubber mix, balsam of Peru, and nickel sulfate; substantial agreement for formaldehyde, bisphenol A epoxy resin, and 4-tert-butylphenol formaldehyde resin; and moderate agreement for potassium dichromate. Conclusion: The Finn Chamber and IQ-Ultra patch tests had a good agreement in the detection of the 10 standard allergens that were tested.