Background Mast cells (MCs) play a key role in allergic diseases through the release of inflammatory mediators, which are responsible of allergic symptoms. Mastocytosis is characterized by an abnormal proliferation and accumulation of mast cells, in which mediators are released intermittingly or continuously. Despite these clinical similarities, few studies have addressed the presence of allergic symptoms in mastocytosis patients, including anaphylaxis.
Objective A prospective evaluation was carried out to study the prevalence of allergic diseases in patients with mastocytosis and their impact on the natural history of mastocytosis.
Methods A questionnaire was given to 210 patients with mastocytosis to evaluate the history of asthma, rhinitis, conjunctivitis, atopic dermatitis, urticaria and anaphylaxis. Patients underwent total IgE, Phadiatop® infant (aeroallergens and food allergens), specific IgE to latex and to Anisakis simplex determinations. Skin tests were done to 72 patients.
Results The prevalence of allergy, as defined by clinical symptoms associated to specific IgE, was 23.9%. Total IgE level was significantly higher in patients with allergy as compared with patients without allergy (median 58 vs. 16.5 kU/L, P<0.0001). Anaphylactic symptoms were present in 36 patients (22%), in nine the allergen was identified. Males had more allergy and anaphylactic symptoms than females (61.5% vs. 38.5% and 72% vs. 28%, respectively).
Conclusions Allergic diseases coexist in patients with mastocytosis with similar frequency as compared with the general population. Anaphylactic symptoms are more prevalent in males with mastocytosis and in patients with elevated IgE.
Capsule summary The prevalence of allergy in mastocytosis is similar to the general population. Anaphylactic symptoms are more prevalent in males and in patients with elevated IgE. The coexistence of atopy does not influence mastocytosis-associated symptoms.