[Clinically mild encephalitis/encephalopathy with a reversible splenial lesion of corpus callosum in a child and literature review].

OBJECTIVE: To investigate the characteristics of a new clinical-image syndrome-mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) of corpus callosum.

METHOD: The clinical and imaging features of one pediatric patient with the diagnosis of MERS were analyzed and the clinical and radiologic data of 44 MERS cases which were reported all around the world were also analyzed.

RESULT: The underlying disease of the patient before the onset was respiratory mycoplasma infection. On the second day of the disease course, the patient presented symptoms of encephalopathy. Brain MRI indicated lesions in the splenium of corpus callosum, centrum semiovate and posterior periventricular white matter. And these lesions recovered completely within 3 weeks. Most of the 44 patients diagnosed with MERS were associated with infectious diseases and completely recovered within two weeks. Symptoms included consciousness disturbance, convulsions and dysarthria. In addition to the splenium, brain MRI also showed lesions in genu of corpus callosum, centrum semiovate and white matter of frontal lobe.

CONCLUSION: The clinical presentations of MERS were sudden onset of symptoms of encephalopathy during acute inflammation. Brain MRI indicated a reversible lesion in the splenium of corpus callosum. Patients recover completely within a few days.