Perioperative management of patients with mastocytosis.

753 March 2014 M ASTOCYTOSIS may be associated with the occurrence of perioperative immediate hypersensitivity reactions. Hypersensitivity corresponds to the reproducible signs or symptoms, initiated by exposure to a defined stimulus at a dose tolerated by normal subjects.1 It is generally accepted that immediate reactions may be delayed for up to an hour.2 Two phenotypes of immediate-type hypersensitivity may occur during the perioperative setting. Although immediate nonallergic hypersensitivity refers to clinical reactions where an immune mechanism can be ruled out (e.g., histamine release belongs to nonallergic hypersensitivity), immediate allergic hypersensitivity refers to those where an immune mechanism can be demonstrated (usually immunoglobulin E [IgE]-mediated).1 Basophil and mast cell degranulation and corresponding inflammatory mediators release occur through a specific IgE-mediated mechanism with subsequent clinical features.3 Mastocytosis is not an allergic disorder but a rare clinical condition with an estimated incidence of 1:150,000.4 In mastocytosis, immediate hypersensitivity usually arises after mast cell degranulation elicited by various nonspecific triggers including psychological, pharmacological and mechanical factors, and temperature changes (table 1). Nevertheless, a concurrent drug-induced IgEmediated reaction may also occur in patients with mastocytosis. The overall incidence of perioperative IgE-mediated anaphylaxis is estimated at 1 in 10,000–20,000 anesthesia procedures.2,5,6 Little is known about the perioperative management of patients with mastocytosis. It remains poorly understood by anesthesiologists, as existing information consists of single-case reports and a few case series. Moreover, there are currently no European or North-American guidelines regarding its perioperative management. The main anesthetic concern is the avoidance of release of histamine and other mast cell mediators. This review seeks to discuss: (1) the various nonspecific triggers that may cause perioperative mast cell degranulation in mastocytosis; (2) a preemptive strategy that allows for a safe perioperative management; (3) the management of immediate hypersensitivity in mastocytosis; and (4) the diagnostic pathway necessary to distinguish nonspecific mast cell degranulation in mastocytosis from other clinical entities.