Clinical Images: Cercarial Dermatitis

Kerry Gardner, MD, Resident, Department of Dermatology and Skin Science, University of British Columbia, BC.
Joseph M. Lam, MD, FRCPC, Clinical Assistant Professor, Department of Pediatrics and Dermatology, University of British Columbia, BC.

Abstract
Cercarial dermatitis (swimmers' itch) consists of urticarial papules that form when the larvae of avian parasitic flatworms penetrate the skin. Cercarial dermatitis is common in the summer months where heaviest recreational swimming occurs, and when the temperature is ideal for amplified schistosome development.

Key Words: cercarial dermatitis (swimmers' itch), non-communicable, water-borne disease.

A previously healthy 3 year-old girl presented with a bilateral pruritic papular eruption on the lower extremities (Figure 1) that occurred 1 week after swimming in coastal waters adjacent to a local beach. Her older sister had a similar eruption which was milder in intensity and duration. The papules lasted for approximately 2 weeks and residual hyperpigmentation faded away after 6-8 weeks. A diagnosis of cercarial dermatitis was made.