What is responsible for her new itchy rash?

An 11-year-old female returned from a family trip to Hawaii with a new itchy rash that started a few days after they were there. She is otherwise healthy except for mild seasonal allergies. Denies exposure to any animals or pets on the trip. 

What is the cause?

A. Asteatotic eczema
B. Ringworm (dermatophyte infection)
C. Candidiasis
D. Cutaneous larva migrans
E. Contact dermatitis

(Answer and discussion on next page)

Answer: Asteatoses

This patient had spent so much time in the water that she developed asteatotic eczema in the pattern of both nummular and eczema craquele. New bathing regimen with moisturizer and a 1-week course of topical corticosteroids resolved the condition. Ringworm would typically not have that many lesions, especially in the absence of animal exposure. Candidiasis would be highly unlikely in a patient who was not immunocompromised. Cutaneous larva migrans is usually more inflammatory, confined to the skin in contact with the sand, fewer lesions, and is not indigenous to Hawaii. Contact dermatitis would not typically produce this pattern and there is no exposure history.