What are these itchy, watery blisters?

After a few days of coping with an intensely itchy eruption on his soles, 42-year-old man sought medical attention. The patient has small, watery blisters and minimal scaling on his feet. He has not purchased new shoes within the past few months.

Can you identify this eruption?

A. Vesicular tinea pedis.

B. Pustular psoriasis.

C. Dyshidrosis.

D. Contact dermatitis.

E. Eczema.

(Answer on next page)

Answer: Vesicular tinea pedis

A potassium hydroxide examination of material from a lesion confirmed the clinical suspicion of vesicular tinea pedis, A. The infection is caused by Trichophyton mentagrophytes, the usual pathogen in tinea pedis. In addition, this patient exhibits an allergic reaction to the dermatophyte. A topical corticosteroid was used to ameliorate the pruritus until antifungal therapy eradicated the infection.