A 17-year-old girl comes to the office due to a rash. She joined the high school cross country running team 2 months ago and has had a progressive itchy rash on her feet since that time. The patient tried replacing her running shoes and socks, but the symptoms continued. Medical history is unremarkable. Examination findings are shown in the image below: Which of the following is the most appropriate treatment for this patient's condition?

Question

A 17-year-old girl comes to the office due to a rash.  She joined the high school cross country running team 2 months ago and has had a progressive itchy rash on her feet since that time.  The patient tried replacing her running shoes and socks, but the symptoms continued.  Medical history is unremarkable.  Examination findings are shown in the image below:  Which of the following is the most appropriate treatment for this patient's condition?

Quizplus · Accepted Answer

11ec25c8_d64f_7156_bc81_5164ef081e95_MD0003_00 This patient has a pruritic rash with maceration and peeling consistent with tinea pedis (ie, athlete foot). Tinea pedis most commonly occurs between the toes (interdigital pattern), but in chronic cases can cause a hyperkeratotic rash extending up the sides of the feet (moccasin pattern). Tinea pedis is primarily caused by dermatophytes, especially Trichophyton rubrum and similar species. The organisms are widespread and often acquired by exposure to public places (eg, athletic facilities, swimming pools) while barefoot. sides of the feet The diagnosis is often made clinically but can be confirmed with a potassium hydroxide preparation of skin scrapings. Tinea pedis can be treated with a variety of topical antifungals, including azoles (eg, miconazole, clotrimazole), allylamines (eg, terbinafine), and tolnaftate. Oral antifungals (eg, fluconazole, terbinafine) are also effective but generally reserved for patients who do not respond to topical treatment. However, nystatin (primarily used for Candida infections) is not effective against dermatophytes (Choice C). (Choice A) Cephalexin can be used to treat mild cellulitis. Although a secondary cellulitis may complicate tinea pedis, it would be expected to cause skin erythema associated with warmth, tenderness, edema, and possibly fever. (Choice D) Permethrin is indicated for treatment of scabies, which can affect the interdigital spaces of the feet but presents with small papules, pustules, and burrows rather than peeling or fissuring. (Choice E) Topical corticosteroids (eg, triamcinolone) are useful for treatment of acute contact dermatitis, which typically presents with erythema and vesicles on exposed skin (eg, hands, sides of the legs). Although these agents can relieve the symptoms of tinea pedis, they may increase the risk of treatment failure and are not routinely recommended. Educational objective: Tinea pedis most commonly presents with a pruritic rash between the toes. The diagnosis is usually made clinically but can be confirmed with a potassium hydroxide preparation of skin scrapings. A variety of topical antifungal agents (eg, miconazole, terbinafine, tolnaftate) is effective for treatment, but nystatin is not effective. References: Superficial fungal infections. (http://www.ncbi.nlm.nih.gov/pubmed/26612371)

A 17-Year-Old Girl Comes to the Office Due to a Rash