Background and purpose: To describe a patient with relapsing remitting MS who was treated with natalizumab for 36 months. First symptoms of presumptive progressive multifocal leukoencephalopathy (PML) appeared 14 weeks after her last natalizumab infusion.
Methods: Neurological examination, MRI and CSF analysis were performed.
Results: The lack of anti-inflammatory treatment response, clinical course, and serial MRI examinations showed lesion development typical for PML on diffusion-weighted and FLAIR MRI. CSF analysis for JC virus was tested negative twice.
Conclusions: This case represents a presumptive PML after discontinuation of natalizumab treatment-similar to the definition established for PML in HIV patients.
Keywords: Progressive multifocal leukoencephalopathy; multiple sclerosis; natalizumab.
Copyright © 2013 by the American Society of Neuroimaging.