[Progressive rubella panencephalitis].

Progressive rubella panencephalitis (PRP) is a slow virus infection of the central nervous system. PRP was first reported in 1974, and fewer than 20 cases have been reported since then. All patients were male who were between the ages of 8 and 21 years at onset, and most had signs of congenital rubella syndrome. Although PRP may exhibit clinical features resembling SSPE, the age at onset is much older and the clinical course is more benign. The main neurological features of PRP are dementia, cerebellar ataxia, and seizures. Increases in antirubella antibody titer and IgG are found in the CSF and diffuse atrophy of the brain with ventricular dilatation may be found on MRI. The pathomechanism of PRP remains unclarified.