[Case of recurrent encephalomyelitis associated with eosinophilia in CSF]

We report a 30-year-old man with recurrent eosinophilic encephalomyelitis. He had a history of childhood asthma and allergic rhinitis. A half year before admission, when he suffered from a headache, a few lesions were indicated by brain MRI at another hospital. From a month before admission, he noticed gait disturbance, sensory impairment, difficulty in micturition, and constipation. Neurological examination revealed moderate muscle weakness in the feet, hypoesthesia below Th6, and bladder-bowel disturbance including impotence. Lumbar T(2) weigthed MRI showed a severe swelling and a hyperintense lesion at the conus medullaris. Brain MRI revealed several asymptomatic white matter lesions. Eosinophilia was documented in the cerebrospinal fluid (CSF) but not in the peripheral blood. Clinical symptoms and MRI findings were remarkably improved after steroid pulse therapy. Note that eosinophils in the CSF were also decreased after the treatment with apoptosis-like cells. We thought that CSF eosinophilia was the core pathogenic feature of this case, but clinical settings that provoke CSF eosinophilia such as parasites and other infectious agents, neuromyelitis optica, atopic myelitis, eosinophilic leukemia and hypereosinophilic syndrome could be ruled out. The remarkable responses to steroids without any additional therapy, compatible with idiopathic eosinophilic syndromes, confirmed that this was a case of idiopathic eosinophilic recurrent encephalomyelitis.