"AM I ALLERGIC TO THE OCEAN?": HIVES IN A YOUNG VACATIONING GIRL

Abstract

Introduction Saline-dependent aquagenic urticaria (SDAU) is a rare form of aquagenic urticaria with Typically 1-3 mm papular lesions, these hives are distributed on the face and neck, affecting mostly adolescent to middle aged women. Onset is usually within 20 minutes of exposure, with resolution within 30 minutes after discontinued exposure. Treatment with antihistamines is typically unsuccessful. Case Description A 7 year old female with chronic spontaneous urticaria and allergic rhinitis presented for evaluation of hives after swimming in the ocean. Onset was at 4.5 years of age; after going in the ocean she developed urticarial lesions on the neck, chest and legs which resolved within 30 minutes of getting out of the water. She developed similar rash on repeat exposure to salinated water in the ocean, salinated pools, and “slime” made with salinated solution, but not with exposure to tap or chlorinated water. Further instances were similarly distributed but later described as a fine papular, pruritic rash, worsening in intensity as she aged despite antihistamine use. In-clinic challenge was completed with gauze soaked with room temperature solutions of tap water, 3.5% saline and 7% saline. After 20 minutes, the gauze was removed and there was erythema and pruritus at the site of the 7% saline solution only. Discussion There have been two described pediatric cases of SDAU. This case is unique in that the patient developed typical urticaria as well as follicular lesions in an atypical distribution (including the chest and legs).