DO_infectious_disease_slim DO_rare_slim NCIthesaurus has material basis in has phenotype has symptom progressive multifocal leukoencephalopathy UMLS_CUI:C0023524 A viral infectious disease that involves reactivation of JC polyomavirus (Betapolyomavirus secuhominis) in immune-compromised individuals which causes the loss of white matter (which is made up of myelin, a substance the surrounds and protects nerve fibers) in multiple areas of the brain. The symptoms include hemiparesis, aphasia, dysarthria, hemianopia, cognitive impairment and coma. SNOMEDCT_US_2025_09_01:22255007 ICD9CM:046.3 DOID:643 GARD:7468 NCI:C26815 PML disease_ontology ICD10CM:A81.2 MESH:D007968 viral infectious disease Cognitive impairment Betapolyomavirus secuhominis hemiparesis dysarthria aphasia coma