Aquagenic pruritus. Water-induced activation of acetylcholinesterase

Polycythemia vera‐associated pruritus and its management

“…Increased skin mast cells [10], mononuclear cells and eosinophils [27], functionally distinct mast cells [29], itching correlates with homozygosity for the JAK2V617F mutation [31] Normal number of skin mast cells [16], acetylcholine mediated [28], increased cutaneous fibrinolytic activity [23] Non-specific lymphocytic peri-venular infiltrate Treatment See Table 3 Symptomatic, Adding sodium bicarbonate to bath water [24] Symptomatic, Emmolients [16], change in bathing habits [16] NA, not applicable; AP, aquagenic pruritus; PV, polycythemia vera.…”

Water-Induced Itching

“…Atopy is [10]. present at about the same rate as in the general popula tion; however, there is an increased incidence of family members affected with AP [10,12,17,19]. Little is known about the natural course, since complete resolution of symptoms may not be communicated.…”

“…15], sudden temperature changes [10. 12, 14] and more rarely heat, cold, physical or emotional stress and pres sure [10], Organic solvents such as ethanol and acetone [7] and hydrogen peroxide [12] did not elicit AP. The examination of the tap water of 4 patients did not reveal a consistent result with regard to pH, electrolyte content or contaminants [Bircher, unpubl.…”

Intradermal Cholinergic Agonists Induce Itch-Associated Response via M3 Muscarinic Acetylcholine Receptors in Mice

“…On the other hand, intradermal injection of ACh elicits the itch sensation in patients with atopic eczema (5). Thus, it has been suggested that ACh acts as endogenous pruritogen in some skin diseases such as cholinergic urticaria and aquagenic pruritus (7). Thus, ACh may be an important itch mediator.…”