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Progressive multifocal leukoencephalopathy after natalizumab monotherapy
Hans Lindå1, Anders von Heijne, Eugene O Major
1Neurology Unit, Division of Internal Medicine, Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden. hans.linda@ki.se
The New England Journal of Medicine
|September 11, 2009
Summary
Progressive multifocal leukoencephalopathy (PML) developed in a multiple sclerosis patient on natalizumab. Early diagnosis using sensitive PCR and plasma exchange improved outcomes.
Area of Science:
- Neuroimmunology
- Viral Pathogenesis
Background:
- Natalizumab is an effective treatment for multiple sclerosis.
- JC virus reactivation can cause progressive multifocal leukoencephalopathy (PML).
Observation:
- A multiple sclerosis patient on natalizumab developed symptoms suggestive of PML.
- Initial JC virus PCR in cerebrospinal fluid was negative, but a more sensitive quantitative PCR confirmed PML after 16 infusions.
- Immune reconstitution inflammatory syndrome (IRIS) occurred post-plasma exchange for natalizumab clearance.
Findings:
- Sensitive quantitative PCR is crucial for early PML diagnosis in natalizumab-treated patients.
- Plasma exchange can accelerate drug clearance.
- IRIS is a potential complication following treatment for natalizumab-associated PML.
Implications:
- This case highlights the importance of vigilant monitoring for PML in patients receiving natalizumab.
- Early and sensitive diagnostic methods are critical for timely intervention.
- Understanding IRIS is important for managing PML treatment complications.
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