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 descriptions | PML diagnostic criteria | ||||
| Clinical features | MRI findings | CSF JCV PCR | Diagnostic category | Number of patients meeting criteria (%) | |
| At first diagnostic work-up | At last follow-up | ||||
| + | + | + | Definite | 10 (35.7) | 18 (64.3) |
| + | − | + | Probable | 0 | 0 |
| − | + | + | 8 (28.6) | 2 (7.1) | |
| + | + | − or ND | Possible | 5 (17.9) | 6 (21.5) |
| − | − | + | 0 | 0 | |
| + | − | − | Not PML | 0 | 0 |
| − | + | − | 5 (17.9) | 2 (7.1) | |
| − | − | − | 0 | 0 | |
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.