Mast cell activation in acquired chronic urticaria-angioedema.

Mast cells play a central role in the pathogenesis of many allergic disorders. They can be activated in different ways. The present study was focused to evaluate the role of mast cells in acquired chronic urticaria-angioedema induced by gastroesophageal reflux. Tryptase, an important marker of mast cell activation, was detected with UniCap Tryptase Fluoroenzymeimmunoassay (Pharmacia & Upjohn AB, Uppsala, Sweden). Eight subjects were studied: four males and four females, aged between 29 and 71 years (mean age: 45 yrs.), suffering from acquired chronic urticaria-angioedema. Results were compared with the results of seven healthy control subjects. Moreover, data were compared with those of 13 subjects (10 males and 3 females, mean age: 24.7 years) suffering from allergic rhinitis. In acquired chronic urticaria-angioedema, serum tryptase levels (mean +/- S.D.: 9.6 +/- 4.3 microg/l) were significantly higher (P < 0.007) than those of the controls (mean +/- S.D.: 3.0 +/- 1.2 microg/l) and higher also than in allergic rhinitis (mean +/- S.D.: 6.1 +/- 2.4 microg/l, P < 0.03). The results underline the central role of mast cells in the inflammation of acquired chronic urticaria-angioedema.