Eosinophils in chronic urticaria: supporting or leading actors?

Although their number may be increased in skin lesions, eosinophils have been rather neglected as possible participants to the pathogenesis of chronic urticaria because of the absence of peripheral eosinophilia in patients with this disease. However, recent data suggest a potentially relevant role played by activated eosinophils both in triggering the tissue factor pathway of coagulation cascade and as a source of vascular endothelial growth factor. Such phenomena seem more pronounced in patients showing a more severe disease. The present study will rediscuss the potential role of this cell line in chronic urticaria in the light of these recent observations.