Clinico-radiological spectrum in enterovirus 71 infection involving the central nervous system in children

Enterovirus 71 infection causes hand, foot and mouth disease in children, and can produce diverse neurologic complications. Epidemics occurring in Korea between 2009 and 2012 resulted in the death of some patients. The present study aimed to clarify the correlation between clinical features and MRI findings in patients presenting with acute neurologic manifestations related to enterovirus 71 infection. Based on their clinical features, the patients were classified into four clinical groups: (1) brainstem encephalitis (n = 17), characterized by myoclonus, tremor, ataxia, and autonomic dysregulation such as pulmonary hemorrhage; (2) aseptic meningitis (n = 2); (3) encephalitis (n = 2), characterized by decreased consciousness, seizure, and fever without myoclonus, tremor, ataxia, and autonomic dysregulation; and (4) acute flaccid paralysis (n = 1). Thirteen of the 17 patients with brainstem encephalitis showed characteristic lesions in the dorsal brainstem and bilateral cerebellar dentate nuclei on brain MRI, whereas three had no abnormality. One of the two patients with meningitis had a small lesion in the left dorsal pons. Two patients with encephalitis had no apparent MRI abnormality. One patient with acute flaccid paralysis of the right leg had contrast-enhancement of the bilateral ventral nerve roots at the lumbar spine level on MRI. Five of 13 patients with lesions in the bilateral dentate nuclei of the cerebellum exhibited no cerebellar symptoms, while two with no cerebellar lesions developed ataxia. Although most patients presenting with neurologic manifestations of enterovirus 71 infection had characteristic clinical features together with typical MRI findings, the clinical features were not necessarily consistent with MRI findings.