Mild encephalitis with reversible splenial (MERS) lesion syndrome due to influenza B virus.

We describe a 16-year-old boy with mild encephalitis with reversible lesions in the white matter and splenium of corpus callosum as a complication of an influenza B virus infection. Although more common in Asiatic children, it can also occur in Caucasian children and adults. There are several possible causes, including metabolic disorders, hypertension and infection, and the prognosis is usually good, even without treatment.

Cerebrotendinous xanthomatosis presenting with asymmetric parkinsonism: a case with I-123-FP-CIT SPECT imaging.

Cerebrotendinous xanthomatosis (CTX) is a rare inherited neurometabolic disease. Clinical symptoms are caused by increased deposition of cholestanol and cholesterol in various tissues. Progressive neurological symptoms are one of the principal manifestations. We report the case of a 44-year-old man who presented with asymmetric parkinsonism. In addition, there were mild bilateral pyramidal signs and a mild polyneuropathy. Brain MRI showed bilateral lesions in the dentate nucleus of the cerebellum and in the substantia nigra. Nuclear brain imaging using I-123-FP-CIT demonstrated an asymmetric reduced presynaptic dopaminergic function of the putamen and caudate nucleus, correlating well with his lateralized bradykinetic-rigid syndrome. CTX was diagnosed based on an increased plasma level of cholestanol, typical cerebellar brain lesions and the causative genetic mutation. CTX presenting with parkinsonism is considered rare and data on the neuroimaging of the dopaminergic deficit are limited.