Aquagenic urticaria recurring after epilation and contact with sea water.

A21-year-old female patient,with a background of infantile atopic eczema, reported a 2-year history of urticaria induced by bathing in the Mediterranean sea. Whealing was restricted to her legs, and would develop after 30min of contact with sea water, but only when this occurred within 3 days after epilation. The reaction disappeared within 30min of the patient getting out of the sea. Contact with swimming pool and tap water had no effect. No other types of inducible urticaria were present. Water challenge testswere performedbymeansof compresses soaked with aqueous 3.5% NaCl and 20% glucose solutions (iso-osmolar with sea water), as well as with tap water, applied on both shaved and unshaved areas of the patient’s thighs, 24 hr after their partial epilation. An urticarial reaction, starting from tiny follicular wheals, developed on the epilated areas challenged with 3.5% NaCl (Fig. 1), and, to a lesser extent, on those challengedwith20%glucose,within20min.Neither solution had any effect on non-epilated skin, and tap water had no effect on either epilated or non-epilated skin. A 5-mg