MRI characteristics and follow-up findings in patients with neurological complications of enterovirus 71-related hand, foot, and mouth disease.

OBJECTIVES This study aimed to investigate the magnetic resonance imaging (MRI) characteristics and clinical and MRI follow-up findings of patients with neurological complications of enterovirus 71-related hand, foot and mouth disease. METHODS Data were collected from 12 patients who developed neurological complications of enterovirus 71-related hand, foot, and mouth disease during an enterovirus-71 outbreak in Hainan Province, China, from May 2008 to October 2011. Patients were followed up for 2 years. RESULTS In the six patients with brainstem encephalitis, MRI showed posterior brainstem abnormalities with hyperintense areas on T2-weighted images and hypointense areas on T1-weighted images. In the four patients with acute flaccid paralysis but no brainstem encephalitis, sagittal MRI images showed linear hyperintense areas in the anterior spinal cord, transverse T2-weighted images showed hyperintense areas in the spinal cord, and contrast-enhanced axial T1-weighted images showed strong enhancement of the anterior horns or nerve roots. In the two patients with aseptic meningitis, MRI showed widening of the subarachnoid space and ventricles. The MRI and clinical signs of aseptic meningitis resolved within 4 weeks in both patients. Patients with isolated pontine abnormalities recovered faster than those with multiple brainstem abnormalities, patients with isolated brainstem encephalitis recovered faster than those with associated acute flaccid paralysis, patients with paralysis of one limb recovered faster than those with paralysis of multiple limbs, and patients with isolated thoracolumbar cord abnormalities recovered faster than those with cervical cord abnormalities. CONCLUSIONS MRI is useful for assessment of the neurological complications of enterovirus 71-related hand, foot, and mouth disease. Patients who develop neurological complications characteristically have MRI abnormalities of the posterior brainstem or bilateral anterior horns of parts of the spinal cord. The MRI findings can help to predict prognosis.