Contact dermatitis of the feet: a study of 53 cases

Contact dermatitis of the feet is a common dermatosis that very often makes patients unable to perform daily activities. The differential diagnosis should be made with other dermatoses, such as tinea, atopic dermatitis, psoriasis, dyshidrosis, and nummular eczema. It is clinically difficult to establish a true diagnosis of contact dermatitis, and the results of epicutaneous tests may not be definite. However, studies undertaken to identify the etiologic agent may lead to a cure for patients.

The objectives of this study were (1) to verify the frequency of contact dermatitis of the feet among a group of patients seen at a public clinic, (2) to determine the type of contact dermatitis, and (3) to determine the most common sensitizers. We selected only patients with eczematous dermatitis from among 1,027 patients at the clinic, and they were patch tested with the Brazilian series.

Of 1,027 patients who submitted to patch tests, 53 (5.2%) presented with dermatosis of the feet. Out of these 53 patients, 37 (70%) had at least one positive patch-test reaction, and the remaining 16 (30%) had negative results.

The presence of dermatosis on the dorsal region of the foot in the majority of the patients with a positive test result was statistically significant (chi2 = 6.02; p < .05). The compounds that caused positive tests more often were rubber-vulcanizing agents, followed by metals and topical medications. The epicutaneous tests were found to be indispensable for the etiologic diagnosis of contact dermatitis of the feet.