Trend of relevant contact allergens of the feet in Spain over a period of 10 years.

Introduction: Allergic contact dermatitis (ACD) of the feet accounts for approximately 10% of all patch tested patients.

Objective: To study the clinical profile of patients with feet dermatitis and relevant contact allergens in Spain over a 10-year period.

Methods: Retrospective observational study of patients with suspected ACD from the GEIDAC (Spanish Research Group on Contact Dermatitis and Cutaneous Allergy) baseline series from eight hospitals in Spain between 2004 and 2014. The clinical data collected from each patient were age, sex, occupation, history of atopic dermatitis, and eczema location.

Results: A total of 450 cases clinically presented dermatitis affecting the feet; of these, 41% of were males and 5.6% were suspected to be of occupational origin. As much as 47% were diagnosed with ACD, 20% with atopic dermatitis/dyshidrotic eczema, and 5% with psoriasis. The "feet group" included statistically significantly more females in the age range of 21 to 60 years. The most frequent relevant contact allergens were potassium dichromate, cobalt(II) chloride, p-tert-butylphenol formaldehyde resin, mercapto mix, and mercaptobenzothiazole.

Conclusions: ACD is the most frequent clinical diagnosis of feet dermatitis in our series. The most frequent allergens are similar to those published in other series of foot ACD in Europe and the trend has not changed in the studied decade.