The relationship between atopy and allergic contact dermatitis in Israeli patients

Introduction: Whether individuals with atopic diseases have a different risk of contact allergy compared to those who are non-atopic is controversial and data are conflicting. Aim: To explore the association between atopy and allergic contact dermatitis (ACD). Material and methods: This retrospective cross-sectional study included 301 patients referred to a tertiary clinic to evaluate ACD. Demographic details including personal and familial mucosal or cutaneous atopic status were recorded. Patch tests were tailored to their clinical presentations and relevant exposures. Results: At least 1 positive patch test reaction was observed in 177 patients (59% of the study cohort), of which 52% had a history of atopic diseases, compared with 44% of patients with a negative patch test result (p = 0.2). Additionally, 147 patients had an atopic background, of which 92 (62%) had ≥ 1 positive patch test result, compared with 55% of non-atopic patients (p = 0.2). Nickel sulphate was the most common contact allergen (13.4% of the patch test reactions). Conclusions: We identified a positive tendency for atopic diseases among individuals with ACD and vice versa. Our study supports the aggregate data from previous studies despite the non-significant differences between the study and control groups. However, further research performed in larger populations of patients is necessary to evaluate the real association between atopy and ACD on a solid basis. Our results indicate the necessity of systematic patch testing in patient setups with atopic background and chronic dermatitis.