Progressive Multifocal Leukoencephalopathy Melissa M. Blessing, DO, Aditya Raghunathan, MD, Lori A. Erickson, MD  Mayo Clinic Proceedings  Volume 93, Issue 1, Pages 123-125 (January 2018) DOI: 10.1016/j.mayocp.2017.11.017 Copyright © 2017 Mayo Foundation for Medical Education and Research Terms and Conditions

Figure These photomicrographs of the cerebellum demonstrate the “histopathologic triad” of PML as well as in situ evidence of infection. A and B, Numerous “bizarre” astrocytes (closed arrows) and a viral nuclear inclusion (open arrow) in an enlarged oligodendryocyte are seen in a background of macrophages. C, Myelin stain (LFB/PAS) shows extensive demyelination with pale white matter instead of normal dark blue white matter. D, In situ hybridization for JC virus DNA is positive in infected cells (closed arrows), confirming the diagnosis. JC = John Cunningham; LFB = Luxol fast blue; PAS = Periodic acid–Schiff. Mayo Clinic Proceedings 2018 93, 123-125DOI: (10.1016/j.mayocp.2017.11.017) Copyright © 2017 Mayo Foundation for Medical Education and Research Terms and Conditions

Mayo Clinic Proceedings 2018 93, 123-125DOI: (10. 1016/j. mayocp. 2017 Copyright © 2017 Mayo Foundation for Medical Education and Research Terms and Conditions