Progressive Multifocal Leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a rare, myelin-damaging disease of the central nervous system (CNS) in a setting of immunosuppression that is superimposed by concurrent autoimmune diseases such as multiple sclerosis and AIDS or simultaneous administration of immune modulatory monoclonal antibody drugs such as natalizumab. The causative agent is a Polyomavirus known as John Cunningham (JC) virus (JCV) that affects oligodendrocytes and astrocytes resulting in focal, extensive and progressive demyelination across the brain. The pathogenesis of JCV latent and active infection is yet to be fully understood despite significant medical research. To date, no therapeutic intervention has been very effective in addressing the health implications of PML. In this article, we review the current knowledge on the life cycle of JCV, pathogenesis of PML, highlight important tools in the diagnosis, potential targets for management and therapeutic intervention of PML.