Flow mediated dilation shows impaired endothelial function in patients with mastocytosis

Abstract Background Mastocytosis is a rare disease characterized by clonal proliferation of mast cells in different organs. Clinical manifestations of mastocytosis are mostly due to the release of mediators from mast cells and, in many cases such as urticaria, flushing, angioedema and anaphylaxis, are expression of biological effects of mediators on endothelial cells. Chronic secretion of mediators in patients with mastocytosis may lead to alteration of endothelial function. Objective To investigate endothelial function in patients with mastocytosis by using a non-invasive technique of flow mediated dilation (FMD). Methods Twenty-five adult patients with indolent and advanced forms of mastocytosis and twenty healthy individuals used as control were enrolled in the study. Ultrasound assessment of FMD was performed by measuring changes in the diameter of brachial artery after 5 minutes of arterial occlusion. Changes in FMD were correlated with clinical parameters and serum tryptase level. Results Patients with mastocytosis had a lower FMD as compared to healthy controls (p Conclusions Endothelial dysfunction, demonstrated by FMD reduction, is detectable in patients with mastocytosis and is more severe in patients with high tryptase levels and advanced disease. Endothelial function appears to be negatively influenced by mast cells proliferation rather than by the severity of mediator-related symptoms.