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Published on: July 4, 2007
Progressive multifocal leukoencephalopathy: A 25-year retrospective cohort study
Pria Anand1, Gladia C Hotan2, Andre Vogel2
1From the Department of Neurology (P.A., A.V., N.V., F.J.M.), Massachusetts General Hospital, Boston; and Department of Brain and Cognitive Sciences (G.C.H.), Massachusetts Institute of Technology, Cambridge. pria.anand@gmail.com.
Objective:
To characterize the risk factors, clinical course, and treatment of patients with progressive multifocal leukoencephalopathy (PML) diagnosed and followed over a 25-year epoch at 2 academic hospitals.
Methods:
Patients with a definite diagnosis of PML were identified by positive CSF PCR for JC virus or histopathology between January 1, 1994, and January 1, 2019. Demographic and PML-specific variables were recorded on symptomatic presentation and at follow-up, including risk factors, clinical outcome, neuroimaging findings, and modified Rankin Scale (mRS) score at last follow-up.
Results:
There were 91 patients with confirmed PML. HIV infection was the most common risk factor, identified in 49% (n = 45). Other frequent risk factors included lymphoma, leukemia, or myelodysplasia, identified in 31% of patients (n = 28); exposure to chemotherapeutic medications (30%, n = 27); and exposure to monoclonal antibody therapies (19%, n = 17). Thirty percent of the cohort was alive at the time of censoring, with a median mRS of 2 points, indicating slight disability at last follow-up. Median survival following PML diagnosis in HIV-infected patients was longer than in HIV-uninfected patients (1,992 vs 101 days, p = 0.024). Forty patients survived more than 1 year after PML symptom onset, of whom 24 were HIV infected (60%). Thirteen patients survived more than 10 years after PML symptom onset, all HIV infected, of the 59 patients diagnosed before June 1, 2009, and eligible for 10-year survivor status (22%).
Conclusions:
We add to the limited literature on PML by reporting its epidemiology in a large observational cohort. These parameters may be useful for future clinical trials that measure survival and clinical outcomes.
Insights
This study analyzed 91 progressive multifocal leukoencephalopathy (PML) cases over 25 years. HIV infection was the most common risk factor, and HIV-positive patients had significantly longer survival.
Area of Science:
- Neurology
- Infectious Diseases
- Epidemiology
Background:
- Progressive multifocal leukoencephalopathy (PML) is a rare, often fatal, demyelinating disease of the central nervous system.
- Understanding PML's risk factors, clinical course, and treatment is crucial for improving patient outcomes.
Purpose of the Study:
- To characterize the risk factors, clinical course, and treatment of patients diagnosed with progressive multifocal leukoencephalopathy (PML).
- To analyze outcomes in a large observational cohort over a 25-year period.
Main Methods:
- Retrospective analysis of 91 patients with confirmed PML (JC virus PCR or histopathology positive) between 1994 and 2019.
- Data collection included demographics, risk factors, clinical presentation, neuroimaging, and modified Rankin Scale (mRS) at follow-up.
Main Results:
- HIV infection was the most frequent risk factor (49%), followed by hematologic malignancies (31%) and immunosuppressive therapies (30% chemotherapy, 19% monoclonal antibodies).
- 30% of patients survived, with a median mRS of 2. Median survival was significantly longer in HIV-infected patients (1,992 days) vs. HIV-uninfected (101 days).
- 40 patients survived >1 year, and 13 survived >10 years, all of whom were HIV-infected.
Conclusions:
- This large cohort study provides valuable epidemiological data on PML.
- Findings highlight the significant impact of HIV status on PML survival and may inform future clinical trial design.
