Is Patch Test Necessary in Children to Solve the Clinical Conundrum of Foot Eczema

Foot eczema in children is a commonly encountered condition but is associated with diverse etiology, thereby posing a diagnostic challenge. These include atopic eczema, juvenile plantar dermatoses, irritant contact dermatitis, and allergic contact dermatitis. Because of the diverse etiology, it is often difficult to distinguish between the conditions clinically, thereby warranting patch testing for the correct diagnosis.

The study was conducted to determine the frequency of positive patch tests among children with foot eczema and to compare them with children with and without atopy.

This was a prospective observational study done on 86 children aged 4 to 17 years presenting with foot eczema in whom patch testing was done using Indian standard series and footwear series and patients' own footwear.

The clinical diagnosis of foot eczema in our study was allergic contact dermatitis (37%), followed by atopic eczema (30%), juvenile plantar dermatoses (17%), and lichen simplex chronicus (15%). Patch test positivity was present in 36% of the cases with clinical relevance in 65% of the cases. The common allergens were rubber allergens and disperse dyes. Of the children who were patch tested, highest patch test positivity rates were seen in allergic contact dermatitis (50%) and juvenile plantar dermatoses (53%). No significant differences were observed with regard to patch test positivity or relevance between children with and without atopy.

The diagnosis of foot eczema in children cannot be made on clinical grounds alone, and patch testing should be recommended in children with any morphological pattern of foot eczema irrespective of presence or absence of atopy, especially in those with long-standing and recalcitrant disease with frequent exacerbations.