Nonallergic triggers for mast cell activation in mastocytosis

The table lists potential nonallergic triggers for episodes of mast cell activation in adults and children with mastocytosis. Individual patients may be sensitive to some of these triggers and not others. In adults, insect stings (especially of Hymenoptera; eg, bees, wasps, etc) can induce severe episodes of hypotensive anaphylaxis, but insect stings are an uncommon trigger in children. In infants and young children, emotional upset, mechanical irritation of the skin, and fever are more typical triggers.