Yama Testinde 168. Saatte Ortaya Çıkan Yeni Pozitifliklerin Prevalansı: Retrospektif Kesitsel Bir Çalışma

Abstract

Objective: Some clinics interpret patch test results 48 hours after application and an additional reading is performed at 72 or 96 hours. Reports in the literature describe delayed positive reaction to some allergens in patients who underwent patch testing for suspected allergic contact dermatitis. However, an additional late reading may be neglected in some clinics. In this study we aimed to identify allergens with delayed positive patch test reactions and to determine the relevance of an additional day 7 (168 hours) patch test reading. Material and Methods: The data of 101 patients who underwent patch testing for suspected allergic contact dermatitis between January 2015 and July 2016 were analyzed retrospectively. Demographic data and patch test results of the patients were evaluated. Allergens without a positive reaction at the 48th and 96th hours but with a positive reaction at the 168th hour were considered as delayed positive patch test reaction. Results: Sixty-four (63.3%) of 101 patients had positive reactions to at least 1 allergen. A total of 125 positive reactions were detected. Of the 125 positive reactions, 85 (68%) were positive at 48 hours reading and 31 (24.8%) turned positive at 96 hours evaluation. Nine (7.2%) of 125 positive reactions were late reactions that turned positive at 168 hours. Nickel sulfate, gold sodium thiosulfate, Cl+Me-isothiazolinone, formaldehyde, tixocortol pivalate and hydrocortisone-17-butyrate, and fragrance mix were detected as allergens causing late positive reactions. Conclusion: We think that late reading at the 168th hour should not be neglected.