Increased cutaneous fibrinolytic activity in aquagenic pruritus.

Aquagenic pruritus is a disease in which itchy prickling skin discomfort is evoked by contact with water at any temperature without observable cutaneous lesions. Little is known about its etiology and pathogenesis. Previous reports show that increased levels of blood histamine and cutaneous mast cell degranulation are present before water exposure and that they increase still further with water challenge. This paper shows that fibrinolytic activity is markedly increased both before and after water exposure, while circulating fibrinolytic activity is normal before water exposure in three cases of aquagenic pruritus. A patient who was asymptomatic at the time of the study had no observed increase in fibrinolytic activity either before or after water challenge, suggesting that the remission of symptoms of aquagenic pruritus and normalization of cutaneous fibrinolytic activity are interdependent factors.