Accepted for Publication: March 7, 2011.
Published Online: May 9, 2011. doi:10.1001/archneurol.2011.103
Author Contributions:Study concept and design: Clifford, Ances, Rosen-Schmidt, Alvarez, and Tyler. Acquisition of data: Clifford, Ances, Costello, Rosen-Schmidt, Andersson, Parks, Perry, Yerra, Schmidt, Alvarez, and Tyler. Analysis and interpretation of data: Clifford, Ances, Andersson, Parks, Perry, Schmidt, Alvarez, and Tyler. Drafting of the manuscript: Clifford, Alvarez, and Tyler. Critical revision of the manuscript for important intellectual content: Clifford, Ances, Costello, Rosen-Schmidt, Andersson, Parks, Perry, Yerra, Schmidt, Alvarez, and Tyler. Administrative, technical, and material support: Clifford, Ances, Andersson, Parks, Perry, and Alvarez. Study supervision: Clifford and Schmidt.
Financial Disclosure: Dr Clifford serves on data safety boards for Millennium, Genzyme, Genentech, and Pfizer. He has been a consultant to Genentech, Wyeth, Bristol-Myers Squibb, Millennium, Biogen Idec, and Pfizer. He has received speaker fees from Biogen Idec, GlaxoSmithKline, and Millennium. He has received travel support from Biogen Idec. He has received research support from Novartis, Biogen Idec, Schering-Plough, Bavarian Nordic, NeurogesX, Tibotec, Pfizer, and Lilly. Dr Tyler has done expert consulting in the area of JC virus and progressive multifocal leukoencephalopathy for Genentech, Biogen Idec, and Pfizer.
Funding/Support: Dr Clifford has received research support from the National Institute of Mental Health, National Institute of Neurological Disorders and Stroke, National Institute of Allergy and Infectious Diseases, and Fogarty Institutes of the National Institutes of Health.
Additional Contributions: We are grateful to the patients and families who contributed to this report. Other physicians contributing to the evaluations in these cases included Indrastha Rasaratnam, MD, Meng Tan, MD, Mark Marriott, MD, Michael Gonzales, MD, and Patricia Desmond, MD.