D2.259 - Beyond Contact with Water: A Case of Aquagenic Urticaria

Objective: The aim of this case report is to present a rare case of aquagenic urticaria along with its diagnostic and therapeutic process.

Case Report: Aquagenic urticaria is a rare type of physical urticaria characterized by pruritic urticarial plaques that develop after contact of the skin with water. A 38-year-old female patient presented with a six-month history of erythema, pruritus, and small urticarial eruptions occurring after contact with water. Symptoms developed regardless of water temperature or source and weretriggered by activities such as hand and face washing, showering, and bathing. In addition, erythema, pruritus, and small urticarial lesions were observed on body areas exposed to tears and sweat. Her complaints were not triggered by exercise, increased body temperature, or cold exposure. There was no family history of similar symptoms. Laboratory investigations revealed no abnormalities. During the water provocation test, pruritus developed on the face and hands following water contact, accompanied by erythema and urticarial lesions at the contact sites. Despite treatment with oral second-generation antihistamines and a short course of oral corticosteroids, the patient’s pruritus and urticarial lesions persisted. Therefore, anti-IgE therapy with omalizumab was initiated with a diagnosis of aquagenic urticaria. Following the third dose of omalizumab, the patient’s symptoms showed marked clinical improvement. The patient, who Works as a nurse, continues her daily life without difficulty related to water exposure while receiving omalizumab therapy.

Conclusion: This case represents one of the rare examples demonstrating the effectiveness of omalizumab in the treatment of aquagenic urticaria. It contributes to the existing literature on the use of omalizumab in aquagenic urticaria and suggests that this therapeutic option should be supported by future studies.