Cercarial dermatitis

This code represents an acute inflammatory skin reaction caused by penetration of the skin by cercariae, the larval stage of certain trematode parasites, typically acquired from contaminated fresh or saltwater. It is characterized by an itchy, papular, or vesicular rash. This condition is also commonly known as "swimmer's itch."

Use this code when documentation clearly indicates a diagnosis of cercarial dermatitis, often following exposure to contaminated water bodies. Supporting documentation should describe the characteristic rash and history of exposure consistent with swimmer's itch.

• Ensure documentation specifies "cercarial dermatitis" or "swimmer's itch" to differentiate from other forms of dermatitis.
• Do not confuse with other parasitic skin infestations, such as scabies or pediculosis, which have distinct codes.
• Consider adding an external cause code (e.g., W69.XXXA for contact with other nonvenomous aquatic animals) if the circumstances of exposure are documented.