Aquatic antagonists: sponge dermatitis.

Sponges from the phylum Porifera exist throughout the world in marine and freshwater environments. Although many encounters with humans are benign, some may lead to local dermatologic manifestations and in rare cases can cause more severe systemic reactions. Initial decontamination is of utmost importance to diminish the severity of the reaction. As contact between humans and coastal environments increases, it is important for physicians to know how to recognize and treat sponge dermatitis.