Idiopathic hypereosinophilic syndrome revealed by central nervous system dysfunction

The idiopathic hypereosinophilic syndrome (HES) is a rare disease, characterised by persistent eosinophilia (> 1500/mm3), without underlying cause, provoking multiple organ system injury. Morbidity and mortality are mostly associated with the HES cardiopathy. Neurological signs are also frequent. Neurological dysfunction can be central (encephalopathy, organic psycho-syndrome) and peripheral (polyneuropathy, mononeuropathia multiplex, autonomic neuropathy, polymyositis). The encephalopathy is not always caused by distant thrombo-embolic events originating from the HES cardiopathy. We describe a patient with idiopathic HES central nervous system dysfunction, in the absence of cardiopathy. Furthermore we briefly discuss pathophysiological aspects, treatment modalities and the prognosis of the HES, in relation to our patient.