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The changing landscape of progressive multifocal leukoencephalopathy
Sachin Kedar1, Joseph R Berger
1Department of Neurology, University of Kentucky College of Medicine, 740 S. Limestone St., Lexington, KY, 40515, USA.
Current Infectious Disease Reports
|May 24, 2011
Summary
Progressive multifocal leukoencephalopathy (PML), a rare neurologic disease, affects immunosuppressed individuals due to JC virus reactivation. Emerging biologic therapies increase PML risk, necessitating effective prevention strategies.
Area of Science:
- Neurology
- Virology
- Immunology
Background:
- Progressive multifocal leukoencephalopathy (PML) is a rare, severe neurologic disease primarily affecting immunosuppressed individuals.
- The JC virus (JCV), a common polyomavirus, causes PML through reactivation of latent infection under immunosuppression.
- The HIV/AIDS pandemic historically increased PML incidence, which declined with highly active antiretroviral treatment (HAART).
Purpose of the Study:
- To highlight the increasing risk of PML with the introduction of new biologic agents targeting specific immune pathways.
- To underscore the need for effective risk mitigation strategies for PML prevention in patients receiving these therapies.
Main Methods:
- Review of existing literature on PML epidemiology and risk factors.
- Analysis of PML incidence trends associated with different immunosuppressive therapies, including biologic agents.
- Identification of specific biologic agents, such as natalizumab and efalizumab, associated with the highest PML risk.
Main Results:
- Biologic agents targeting the immune system are expanding the population at risk for PML.
- Natalizumab and efalizumab are associated with the highest risk of developing PML among biologic therapies.
- PML can occur with other biologic agents, indicating a broader risk across this treatment class.
Conclusions:
- The expanding use of biologic therapies necessitates proactive strategies to manage and prevent PML.
- Effective risk mitigation is crucial for patients undergoing immunosuppressive therapy with biologic agents.
- Further research into PML pathogenesis and prevention is warranted given the evolving treatment landscape.
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