History:

Case of Dr 

52 yo female 
Intensely itchy papular lesions on her trunk a few days after snorkelling while on holidays in a South Pacific Island country 3 weeks ago.
She had used the following with minimal respite from the itch - phenergan,hydrocortisone cream and permethrim.
She was subsequently placed on prednisolone tablets 25mg tid (ab initio;to be followed by tapering down the track) and diprosone cream - bd.
A follow-up has been arranged in seven days.

Good case. The individual lesions are typical of a papular urticaria but with a suggestion of a vesicle on top. Hence looks dermatitic. Swimmer's itch has the lesions on exposed areas rather than under the swimming costume.
Dermnet on Seabather's eruption (Submitted By: Dr Ian McColl)