MRI and brain biopsy findings in a 62-year-old man who initially presented with progressive development of gait dysfunction, urinary incontinence, and encephalopathy over the course of two weeks following four days of a gastrointestinal illness.
(A) Axial (T2/FLAIR) MRI showing supratentoria white matter hyperintensities extending from the periventricular region to the subcortical fibers.
(B) Sagittal (T2/FLAIR) MRI showing diffuse periventricular white matter intensities.
(C) Axial (T2/FLAIR) MRI showing interval improvement and resolution of the periventricular white matter lesions.
(D) Sagittal (T2/FLAIR) MRI demonstrating the improvement of the periventricular white matter lesions.
(E) H&E stain shows areas of pallor containing macrophage that represent areas of demyelination (original magnification 200x).
(F) Clusters of macrophages in the areas of demyelination are highlighted by immunohistochemical staining for macrophage marker CD68 (original magnification 200x).
(G) Relative preservation of axons that are seen to traverse the macrophage rich areas of demyelination is demonstrated on neurofilament immunohistochemical stain (original magnification 400x).
(H) Multiple pink areas of myelin loss are present in the background of normal appearing blue staining cerebral white matter on Luxol Fast Blue/PAS stain (original magnification 100x).
