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Question: Rash

A 10yo girl comes home from a family vacation to Florida in June, where she swam in the ocean. She has an itchy rash in the area covered by her bathing suit that started soon after swimming in the ocean and is still present 3 days later.


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What is this itchy rash?

pemsou5_wp • August 1, 2017

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  1. Kelly August 7, 2017 - 3:22 pm Reply

    C. Rash due to tiny jellyfish larvae (“Seabather’s eruption”)
    Seabather’s eruption is caused by a hypersensitivity reaction to the larvae of thimble jellyfish Linuche unguiculata. The bathing suit traps the larvae against the skin, and they release venom. It occurs May-August commonly, along the Atlantic coastline of Florida. It has been reported in Mexico, Caribbean, and Brazil also. An itchy rash lasts 2 weeks, and patients can have mild systemic symptoms too, including fever. Treatment includes topical steroids and antihistamines. The rash is not in a dermatomal distribution and is not urticarial (urticaria usually don’t persist for 3 days unchanged also). Phytophotodermatitis occurs when sun hits skin that has had plant chemicals (classically, lime juice) on it. Reverse sunburn is not a thing – I made it up.

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