BACKGROUND: Indolent systemic mastocytosis (ISM) without skin lesions (ISMs-) shows a higher prevalence in males, lower serum baseline tryptase levels, and KIT mutation more frequently restricted to bone marrow (BM) mast cells (MCs) than ISM with skin lesions (ISMs+). Interestingly, in almost one-half of ISMs- patients, MC-mediator release episodes are triggered exclusively by insects. OBJECTIVE: We aimed to determine the clinical and laboratory features of ISMs- associated with insect-induced anaphylaxis (insectISMs-) versus other patients with ISM. METHODS: A total of 335 patients presenting with MC activation syndrome, including 143 insectISMs-, 72 ISMs- triggered by other factors (otherISMs-), 56 ISMs+, and 64 nonclonal MC activation syndrome, were studied. RESULTS: Compared with otherISMs- and ISMs+ patients, insectISMs- cases showed marked male predominance (78% vs 53% and 46%; P < .001), a distinct pattern of MC-related symptoms, and significantly lower median serum baseline tryptase levels (22.4 vs 28.7 and 45.8 μg/L; P ≤ .009). Moreover, insectISMs- less frequently presented BM MC aggregates (46% vs 70% and 81%; P ≤ .001), and they systematically showed MC-restricted KIT mutation. CONCLUSIONS: ISMs- patients with anaphylaxis triggered exclusively by insects display clinical and laboratory features that are significantly different from other ISM cases, including other ISMs- and ISMs+ patients, suggesting that they represent a unique subgroup of ISM with a particularly low BM MC burden in the absence of adverse prognostic factors.
Nonaggressive systemic mastocytosis (SM) without skin lesions associated with insect-induced anaphylaxis shows unique features versus other indolent SM
ZAMO', Alberto
2014-01-01
Abstract
BACKGROUND: Indolent systemic mastocytosis (ISM) without skin lesions (ISMs-) shows a higher prevalence in males, lower serum baseline tryptase levels, and KIT mutation more frequently restricted to bone marrow (BM) mast cells (MCs) than ISM with skin lesions (ISMs+). Interestingly, in almost one-half of ISMs- patients, MC-mediator release episodes are triggered exclusively by insects. OBJECTIVE: We aimed to determine the clinical and laboratory features of ISMs- associated with insect-induced anaphylaxis (insectISMs-) versus other patients with ISM. METHODS: A total of 335 patients presenting with MC activation syndrome, including 143 insectISMs-, 72 ISMs- triggered by other factors (otherISMs-), 56 ISMs+, and 64 nonclonal MC activation syndrome, were studied. RESULTS: Compared with otherISMs- and ISMs+ patients, insectISMs- cases showed marked male predominance (78% vs 53% and 46%; P < .001), a distinct pattern of MC-related symptoms, and significantly lower median serum baseline tryptase levels (22.4 vs 28.7 and 45.8 μg/L; P ≤ .009). Moreover, insectISMs- less frequently presented BM MC aggregates (46% vs 70% and 81%; P ≤ .001), and they systematically showed MC-restricted KIT mutation. CONCLUSIONS: ISMs- patients with anaphylaxis triggered exclusively by insects display clinical and laboratory features that are significantly different from other ISM cases, including other ISMs- and ISMs+ patients, suggesting that they represent a unique subgroup of ISM with a particularly low BM MC burden in the absence of adverse prognostic factors.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.