Progressive multifocal leukoencephalopathy Progressive multifocal leucoencephalopathy :? . Progressive multifocal leucoencephalopathy is a progressive disorder cause by J.C. virusdeg. . The main cells affected in the disease are oligodendrocytesdeg. . Since oligodendrocytes are concerned with myelination, progressive multifocal leucoencephalopathy is characterized by multifocal areas of demyelinationQ of varying size distributed throughout the brain but sparing the spinal cord and optic nerves. Pathology . Besides demyelination there are characteristis cytological alterations in both astrocytes and oligodendrocytes : - AstrocytesQ . Enlarged and contain, hyperchromatic, deformed and bizarre nuclei and frequent mitotic figures. OligodendrocytesQ . These have enlarged densely staining nuclei that contains virus inclusions.formed by crystalline arrays. Symptoms of progressive multifocal leucoencephalopathy :? Visual defects (45%) --> Homonymous hemianopia, Conjugate gaze abnormalities Mental impairment (38%) Dementia, confusion, personality changes Weakness --> Hemi or monoparesis and ataxia Seizures (20%) ---> Speech defect aphasia, hemiparesis, ataxia Focal neurological signs . Progressive multifocal leucoencephalopathy is predominantly seen in patients with immunosuppressive disorders: ? . Most commonly associated conditions are: ? - AIDS (80%)Q - Hematological malignancies (13%) - Transplant recipients (5%) - Chronic inflammatory disease (2%) Prognosis of progressive multifocal leucoencephalopathy . In most cases death occurs in 3-6 months .from onset of neurological symptoms and even more rapidly in patients with AIDS unless aggressive interetrul treatment is undeaken. Diagnosis . MRI 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 multrfocal asymmetric coalescing white matter located periventricularly. . These lesions have increased signals on T2 and FLAIR images and decrease signal on T,-weighted images. . PML lesions are classically nonenhancingQ. . Other impoant diagnostic tool in PML is the PCR amplification of JCV DNA. . The PCR amplification of JCV DNA in association with typical MRI lesion in the appropriate clinical setting is diagnostic of PML. I am not sure of the answer, visual symptoms, aphasia dysahria are commonly seen in PML.