Foot eczema: The role of patch test in determining the causative agent using standard series

Abstract

Foot dermatitis refers to the predominant involvement of feet in the eczematous process. This study is undertaken to determine the clinical pattern and causative agent in foot eczema and to evaluate the role of patch testing in determining the causative agent of foot eczema. Data was collected from 50 patients with foot eczema, who attended the out-patient department. The patch test was performed using Indian standard series. Patch test was positive in 88% of the patients. The most common site affected was the dorsal aspect of the foot (48%) and scaly plaque was the predominant morphological pattern. The highest number of patients (24%) showed positive reactions to mercaptobenzothiazole (MBT) and the lowest (4%) to neomycin sulfate. Rubber and rubber chemicals have been reported worldwide to be the most common sensitizer causing foot eczema. Thus, patch test has a major role in finding out the cause of foot eczema.

Clinico-demographic profile of patients with foot dermatitis: A cross-sectional study with special reference to patch test results

“…Pruritus was the commonest symptom while scaling and crusting were the commonest presentations. Similar observations have been made by other authors[ 4 7 ] while Suryanarayan et al . [ 7 ] recorded papules and vesicles as the commonest presentation.…”

“…Our patients showed a female preponderance (55.2%); this finding is consistent with that of other similar studies. [ 2 4 5 ] Furthermore, housewives were most commonly affected (31%), thus, corroborating the findings of Huda et al . [ 5 ] This may be attributed to the fact that housewives are more prone to come in contact with different allergens owing to their nature of work and more frequent change of footwear compared to men.…”

“…Priya et al . [ 4 ] also implicated footwear as the commonest aggravating agent in their study; however, 48% of their patients reported worsening during winter. Summer exacerbation in our study may be explained by the habit of wearing footwear without socks and the role of high humidity in our area.…”

“…In our study, the most common age group affected by foot dermatitis was 11–20 years which is slightly younger when compared to other similar studies that recorded maximum occurrence between 21 and 30 years. [ 2 4 5 6 ]…”

“…This value is low when compared to other similar studies in which 50%–80% of patients showed a positive patch test reaction. [ 2 4 5 ] This may be explained by the possible omission of some antigens in the Indian standard series, which are yet to be recognized. Thus, further studies are needed to identify these concealed antigens and include them in the Indian standard series.…”