[A boy with Churg-Strauss syndrome and thrombosis associated with eosinophilia].

A 13-year-old boy, recently diagnosed as having Churg-Strauss syndrome, presented with a thrombus at the level of the aortic bifurcation. Echocardiography revealed a left-ventricular thrombus as well. He was treated by means of surgical thrombectomy, corticosteroids, heparinisation and a coumarine derivative. Eosinophilia (an increase in the number of eosinophilic granulocytes in the circulation or tissues) occurs in various diseases, such as allergic diseases, parasitic infestations, haematologic diseases and autoimmune diseases like the rare Churg-Strauss syndrome. It appears likely that eosinophilia played an important role in the development of both thrombi in the described patient. Eosinophils produce cationic proteins that may inhibit the effect of natural anticoagulants. Infiltration of eosinophils may also cause endocardial damage with the subsequent formation of intracardial thrombi.