Is this boy's rash an allergy to athletic shoes?

Dermclinic Case:This child presents with painful, cracked feet that limit his ability to play sports with his friends. It has been a problem for years, and his parents are looking to cure it once and for all. Is this an allergy to his athletic shoes? Is there something lacking in his diet? Answer on next page. Dermclinic–Answer Case: Juvenile plantar dermatosis (JPD) produces a "glazed" erythema of the soles, usually limited to the forefoot. The condition is associated with scaling, painful hyperkeratosis and fissures that are accentuated in the flexural creases of the toes and on the weight-bearing areas. JPD is often present in atopic children (in whom the disorder is often relatively difficult to control), but it is not limited to them. JPD produces a distinct morphology that does not require further testing. Tinea pedis is unusual in children and, if present, will have associated findings in the web spaces, the dorsal foot, and the nail plates--all of which are spared in JPD. A contact allergy to footwear would be a logical thought. As a rule, however, the dorsal aspect of the foot is involved. In the case of a reaction to a material in the in-sole of the shoe, the involvement is not likely to be accentuated on the forefoot. Also, contact allergy commonly presents as a blistering morphology. The best "bedside" test is to feel the child's sock to see whether it is damp. The etiology of JPD is unknown, but I subscribe to the theory that the cutaneous changes result from rapid drying of the skin after continuous saturation in footwear. The condition could just as easily be called "running shoe dermatitis," "rubber boot dermatitis," or "snow boot dermatitis" (ie, occlusive footwear) depending on your specific locale and the time of year of the disease flare. I have not seen this condition develop in persons who restrict their footwear to sandals, but our sandal season in Canada is short. JPD is a chronic condition that persists year-round. Flares occur depending on the skin's local environment. There is generally a dramatic improvement during puberty; the condition rarely persists into adulthood. I recommend that patients keep their feet as dry as possible. This means wearing fresh cotton socks, leather shoes, a second boot liner for alternate-day use and, when possible, the wearing of "breathable" shoes. I ask parents to apply an emollient to the skin as soon as the footwear is removed in an attempt to maintain the hydration of the skin and reduce the rapidity of the evaporation. I also recommend twice-daily applications of a midstrength topical corticosteroid to inflamed areas to reduce the hyperkeratosis and fissuring. If fissuring has already occurred, I ask parents to apply a methylmethacrylate glue to "caulk" the fissures. This reduces the pain dramatically while we intensify our efforts to apply the emollients and topical corticosteroid.