Purpose: Idiopathic hypereosinophilia syndrome (iHES) is classically defined as prolonged peripheral eosinophilia and multiple organ involvement. The involvement of the heart can lead to intraventricular thrombus because of infiltration of the endomyocardium by eosinophils. Cerebral infarction has been ascribed to thromboembolic events originating from intraventricular thrombus.
Case report: A 67 year-old woman with hypereosinophilia for 6 months presented acute weakness of the right limbs. Left hydranencephaly and absence of the left internal carotid artery were found on brain computed tomography. Brain magnetic resonance imaging (MRI) showed multiple infarctions at bilateral hemispheres. An intraventricular thrombus was detected both in transesophageal echocardiography and in heart MRI. Hypereosinophilia responded well to steroid use and warfarin was used for stroke prevention.
Conclusions: Complete evaluation of systemic involvement in iHES is mandatory and early intervention may prevent deterioration of this disease. Both cardiogenic embolism and endothelial damage related to circulating eosinophils may contribute to the occurrence of stroke in this patient.