JCV-associated CNS diseases
| Types of PML | Clinical Presentation | Imaging Appearance | Histopathology |
|---|---|---|---|
| cPML | Focal neurologic signs depending on the location of lesions | T1 hypointense (to white matter) and T2 hyperintense (to gray matter) lesions in the subcortical U-fiber rather than in periventricular white matter; diffusion restriction at the margin; no enhancement | Severe demyelination; swollen oligodendrocytes with enlarged densely basophilic nuclei filled with eosinophilic inclusion bodies; bizarre astrocytes; absent/minimal inflammation |
| iPML | iPML in IRIS presents with aggravated cPML symptoms; iPML in the non-IRIS setting has similar or aggravated cPML symptoms | Peripheral or rim enhancement with or without mass effect and vasogenic edema | Similar to cPML plus marked inflammatory reaction characterized by diffuse or focal perivascular mononuclear cell (mainly CD3) infiltration |
| JCVGCN | Cerebellar symptoms including ataxia and dysarthria | MR findings are negative in early stage; isolated cerebellar atrophy with T2 hyperintensity in later stage of the disease | Isolated infection of the cerebellar granule cell neurons sparing oligodendrocytes |
| JCM | Similar to viral meningitis | No specific imaging finding | CSF positive for JCV DNA |
| JCE | Abnormal higher CNS function without focal neurologic deficit | Predominant cortical T2 hyperintensity with involvement of white matter in later stage of the disease | Extensive infection of the pyramidal cell neurons with meager infection of oligodendrocytes |