Table 1

Categories of diagnostic certainty for PML diagnosis according to the PML diagnostic criteria,3 and its application to the Dutch-Belgian NTZ-PML cohort

Possible case descriptionsPML diagnostic criteria
Clinical featuresMRI findingsCSF JCV PCRDiagnostic categoryNumber of patients meeting criteria (%)
At first diagnostic work-upAt last follow-up
+++Definite10 (35.7)18 (64.3)
++8 (28.6)2 (7.1)
++− or NDPossible5 (17.9)6 (21.5)
+Not PML00
+5 (17.9)2 (7.1)
  • Percentages were rounded and may not total to 100%.

  • CSF, cerebrospinal fluid; IRIS, immune reconstitution inflammatory syndrome; JCV, John Cunningham virus; NTZ, natalizumab;PML, progressive multifocal leukoencephalopathy; ND, not determined.