Aquagenic urticaria

Aquagenic urticaria
Synonyms	Water allergy
Pronounce	N/A
Specialty	N/A
Symptoms	Hives, itching
Complications	N/A
Onset	Childhood or adolescence
Duration	Chronic
Types	N/A
Causes	Contact with water
Risks	Family history
Diagnosis	Clinical diagnosis
Differential diagnosis	Cholinergic urticaria, Cold urticaria, Solar urticaria
Prevention	N/A
Treatment	Antihistamines, Phototherapy, Barrier creams
Medication	N/A
Prognosis	N/A
Frequency	Very rare
Deaths	N/A

A rare condition characterized by hives upon contact with water

Aquagenic urticaria is a rare form of physical urticaria where the skin develops hives or urticaria after exposure to water, regardless of its temperature. This condition is sometimes referred to as "water allergy," although it is not a true allergy in the immunological sense.

Pathophysiology

The exact mechanism of aquagenic urticaria is not well understood. It is hypothesized that water interacts with a component in or on the skin, leading to the release of histamine or other mediators from mast cells. This results in the characteristic wheals and itching associated with the condition. Unlike other forms of urticaria, aquagenic urticaria does not involve an immunoglobulin E (IgE)-mediated allergic response.

Clinical Presentation

Patients with aquagenic urticaria typically present with small, itchy wheals that appear within minutes of water exposure. These wheals can occur anywhere on the body but are most commonly seen on the upper body, arms, and neck. The hives usually resolve within 30 to 60 minutes after drying off. The condition can be triggered by any form of water, including rain, sweat, tears, and even saliva.

Diagnosis

The diagnosis of aquagenic urticaria is primarily clinical, based on the patient's history and the characteristic appearance of the hives after water exposure. A water challenge test, where water is applied to the skin under controlled conditions, can be used to confirm the diagnosis. Other forms of urticaria and dermatological conditions should be ruled out through a thorough clinical evaluation.

Management

Management of aquagenic urticaria involves avoiding triggers and symptomatic treatment. Patients are advised to minimize water exposure and to use protective barriers such as oils or creams that can prevent water from contacting the skin. Antihistamines are commonly used to alleviate symptoms. In some cases, phototherapy or other treatments may be considered.

Prognosis

Aquagenic urticaria is a chronic condition, but it is not life-threatening. The severity of symptoms can vary over time, and some patients may experience improvement with age. Ongoing management and lifestyle adjustments are often necessary to control symptoms.

Related pages

• Urticaria
• Mast cells
• Histamine
• Allergy