Aquagenic urticaria: report of a case and review of the literature.

OBJECTIVE

To present a case of aquagenic urticaria and to review the literature regarding this very rare physical urticaria.

METHOD

We described the clinical history of a patient with aquagenic urticaria. A water challenge test was performed, with plasma histamine levels measured before and after the challenge.

RESULT

Our patient presented with a history of severe itching and wheals within five minutes of contact with water, regardless of its temperature or source (sea or tap water). A water challenge produced hives but serum histamine levels did not change. Prophylaxis with antihistamine or anticholinergic medications was not effective.

CONCLUSION

Exposure to water can cause urticaria in susceptible patients and antihistamine and anticholinergic medication may not prevent the reaction. The mechanism of this phenomenon remains poorly understood.