Gutartiger Verlauf Einer JC-Virus-assoziierten Kleinhirnatrophie Nach Langjähriger Natalizumab-Behandlung Bei Schubförmiger Multipler Sklerose

Besides the classic progressive multifocal leucoencephalopathy (PML), infection with JC virus can cause isolated cerebellar atrophy by infecting cerebellar granular cells, known as JC virus-associated granule cell neuronopathy (JCV GCN). We report here the third case of JC virus-associated cerebellar atrophy after long-term treatment with natalizumab for relapsing-remitting multiple sclerosis. Diagnosis was made at a time when there were few clinical symptoms but already clear cerebellar atrophy could be seen in MR tomography. The clinical outcome of the patient is good although the patient has undergone an immunoreconstitution syndrome. Besides signs of classic PML, patients under natalizmab treatment must be monitored for functional and structural cerebellar deficits.