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Washington University Experience | VASCULAR | Vasculitis - PACNS | 13A0 Case 13 History
Case 13 History ---- The patient is a 15-year-old girl who initially presented in September of 2014 with abnormal motor symptoms, characterized by the patient holding her left upper extremity as if it were in a sling. Her hands became more contracted, and she began to have contractures of her Achilles tendons bilaterally, as well as a mild limp in her left leg. Per report, an MRI scan at that time was felt to demonstrate "scarring." The patient was then referred to SLCH, where MR imaging performed on January 23 showed numerous enhancing lesions in the right cerebral hemisphere and midline cerebellum, most of which were centered in gray matter. There is extensive surrounding edema throughout the right cerebral white matter, as well as atrophy of the right cerebral hemisphere. The patient was also placed on antiepileptics due to the potential for seizure activity. The patient reportedly experienced a "shivering episode" just prior to that. Operative procedure: Craniotomy for open brain biopsy of right temporal lesion. ---- Sections of the "right temporal lesion" show fragments of cerebral cortex and white matter with prominent medium and small sized vasculitic and vasculopathic changes, as well as patchy areas of reactive astrocytosis. There is a prominent inflammatory infiltrate around and within the vessel walls. The infiltrate is composed predominantly of lymphocytes, plasma cells, and histiocytes. Focal areas show a predominance of plasma cells. Giant cells are not identified. Although ill-formed collections of histiocytes as well as microglial nodules are noted, no true granulomatous inflammation is seen. A subset of vessels shows destruction of vessel walls, including some examples of fibrinoid necrosis. Elsewhere, there is endarteritis obliterans with structures suggestive of recanalization. The adjacent tissue shows, in addition to the reactive astrocytosis, prominent microglial activation. An immunostain for smooth muscle actin highlights both destroyed vessel walls, foci of recanalization, and remaining intact vessel walls. A glial fibrillary acidic protein immunostain (GFAP) demonstrated reactive astrocytosis. A CD68 immunostain highlights both the histiocytic inflammation around affected vessels, as well as microglial activation in adjacent brain parenchyma. CD3 demonstrates numerous, reactive T-lymphocytes, both in a perivascular localization as well as scattered throughout parenchymal tissue. A CD20 immunostain highlights focal collections of CD20+ positive cells. Given the predominance of plasma cells in focal areas as well as endarteritis obliterans, an immunostain for treponema pallidum was performed which was negative. Given the vasculocentric pattern of lymphocytic inflammation, an EBV-driven process was likewise considered, but in situ hybridization for EBV encoded small RNAs (EBER) was negative. Finally, a Luxol fast blue-periodic acid Schiff (LFB-PAS) was performed, and demonstrates no appreciable selective loss of white matter. Immunostains for HSV-1 and HSV-2 were also negative. ---- In summary, the histomorphological and immunohistochemical features in this case demonstrate cerebral cortex and white matter involved by a vasculitic and vasculopathic process, with reactive astrocytosis and incipient microinfarcts in the adjacent brain parenchyma. Nevertheless, these findings in conjunction with the imaging characteristics of right-sided atrophy as well as presence of enhancing lesions limited to only right side of the hemi-brain are somewhat perplexing. It is unclear whether these morphological changes represent a spectrum of Rasmussen's encephalitis as clinically suspected or belong to any other distinctive category. In any case, the most conspicuous pathology in this biopsy appears to be vasculitis and vasculopathic changes.
