Lesson of the Week: Seabather's eruption—a case of Caribbean itch

Abstract

Seabather's eruption is an intensely pruritic dermatitis that occurs after exposure to seawater and affects the areas of the body covered by swimwear. It has probably existed for centuries, but formal reports of it are relatively recent.1 With the increasing popularity of foreign travel, seabather's eruption is likely to be seen more often in patients returning from tropical climes. Larvae of species belonging to the phylum Cnidaria—which comprises jellyfish, corals, sea anemones, and hydra—have been implicated as the cause of this condition.2 3 4 The members of this phylum share a similar stinging mechanism, which is mediated by subcellular organelles called nematocysts. We report two recent cases of seabather's eruption caused by the larvae of thimble jellyfish (Linuche unguiculata). Seabather's eruption should be suspected if there is a history of exposure to seawater followed by the appearance of a papular, pruritic rash affecting the areas covered by the swimsuit In May a 31 year old accountant and her husband travelled to Cancun, on the Caribbean coast of Mexico, for their honeymoon. On the last day of the trip they took a final swim in the ocean, and within minutes of entering the water they became aware of a …