CASE STUDIES:

By Dr. Benjamin Barankin

Question:   What is the diagnosis?

• Porphyria cutanea tarda
• Psoriasis
• Allergic contact dermatitis
• Bullous impetigo
• Bullous scabies

Answer:

Allergic contact dermatitis of the dorsal foot can be associated with exposure to plants such as poison ivy, poison oak, or poison sumac, exposure to dyes used in shoes and sneakers, or topical medicaments. In her case, it was a pair of new leather shoes.

Dye and other allergens are present in high concentrations in new shoes and are most likely to cause a reaction. Heat and perspiration may cause dyes in shoes or sneakers to leach out to the skin, worsening the condition. The dye may not be visible on the sock or skin, but if the person is allergic to it, a pruritic eruption may develop within 1 or 2 days.

Treatment involves avoiding the offending allergen (consider patch testing) and using a potent topical steroid cream with an oral antihistamine. Topical antibiotic ointments can be beneficial to prevent secondary infection. If the reaction is severe or more widespread, a short course of oral steroids can be beneficial.

About the Author:

Dr. Benjamin Barankin is a dermatologist and widely published author and researcher. He has an interest in medical dermatology, as well as in cosmetic procedures such as sclerotherapy, lasers, and fillers. Dr. Barankin combines his interest in the humanities with his knowledge of medical & cosmetic dermatology to optimize the care of his patients with skin concerns.
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