<prompt> Inclusions in oligodendrogliocytes is a feature of -Creutzfeldt-Jakob diseaseCIDPHSVProgressive multifocal leukoencephalopathy  <response>: Progressive multifocal leukoencephalopathy: -Progressive multifocal leukoencephalopathy is a progressive disorder cause by J.C. virus The main cells affected in the disease are oligodendrocytes.Since oligodendrocytes are concerned with myelination, progressive multifocal leukoencephalopathy is characterized by multifocal areas of demyelination of varying size distributed throughout the brain but sparing the spinal cord and optic nerves.PathologyBesides demyelination there are characterises cytological alterations in both astrocytes and oligodendrocytes: -Astrocytes Enlarged and contain, hyperchromatic, deformed and bizarre nuclei and frequent mitotic figures.OligodendrocytesThese have enlarged densely staining nuclei that contains virus inclusions formed by crystalline arrays.Symptoms of progressive multifocal leukoencephalopathy: -Visual defects 45 Homonymous hemianopia, Conjugate gaze abnormalitiesMental impairment 38 Dementia, confusion, personality changesWeakness Hemi or monoparesis and ataxiaSeizures 20 Speech defect aphasia, hemiparesis, ataxiaFocal neurological signsProgressive multifocal leukoencephalopathy is predominantly seen in patients with immunosuppressive disordersMost commonly associated conditions are: -AIDS 80QHematological malignancies 13Transplant recipients 5Chronic inflammatory disease 2Prognosis of progressive multifocal leukoencephalopathyIn most cases, death occurs in 3-6 months from onset of neurological symptoms and even more rapidly in patients with AIDS unless aggressive interetruvial treatment is undertaken.DiagnosisMRI is used for the diagnosis of PML.MRI is better than CT scan in the diagnosis of PML and is frequently used for the diagnosis of PML.On MRI the lesion appears as multifocal asymmetric coalescing white matter located periventricular.These lesions have increased signals on T2 and FLAIR images and decrease signal on T-weighted images.PML lesions are classically nonenhancingQ.Another important diagnostic tool in PML is the PCR ampli 