Intimal thickening of meningeal arteries after serial corticectomies for Rasmussen encephalitis.

Rasmussen encephalitis is a rare cause of intractable epilepsy in children. Between 2008 and 2010, 4 patients had second cortical resections performed after a primary corticectomy for Rasmussen encephalitis. In each case, we observed some degree of vessel wall change in leptomeningeal arteries, consisting of moderate to moderately severe intimal hyperplasia. The intervals between original resection and second operation ranged from 8 months to 10 years. Ages of the patients ranged from 9 to 12 years at their first resection and from 10 to 19 years at the time of revision. Four other Rasmussen encephalitis cases operated upon in the years 2006 to 2010 and 2 surgical revisions for severe cortical dysplasia, 1 for mild cortical dysplasia and 1 for recurrent dysembryoplastic neuroepithelial tumor, did not show significant vascular abnormalities (with surgical intervals of 10 months to 16 years). Leptomeningeal intimal hyperplasia appears to develop in the interval between repeated cortical resections for Rasmussen encephalitis, an inflammatory disorder. The pathogenesis of this vascular change may be related to meningeal inflammation in Rasmussen encephalitis. This finding in children undergoing surgical resection for Rasmussen encephalitis may itself lead to "secondary" ischemic change that contributes to worsening of epilepsy.

Increased cortical expression of FK506 binding protein-51 in HIV-associated neurocognitive disorders.

FK506 binding protein (FKBP)-51 and FKBP52 act as molecular chaperones to control glucocorticoid receptor (GR) sensitivity. Dysregulation of proteins involved in GR-mediated signaling can lead to maladaptive stress response and aging-related cognitive decline. As HIV infection is related to chronic stress, we hypothesized that altered cortical expression of these proteins was associated with HIV-associated neurocognitive disorders (HAND). We used quantitative immunohistochemistry to assess expression levels of these proteins in the mid-frontal gyrus of 55 HIV-infected subjects free of cerebral opportunistic diseases compared to 20 age-matched non-HIV controls. The immunoreactivity normalized to the neuroanatomic area measured (IRn) for FKBP51 was increased in HIV subjects both in the cortex and subcortical white matter (p < 0.0001, U test), while no significant alterations were observed for GR or FKBP52. Notably, the cortical FKBP51 IRn was higher in HAND subjects than in cognitively normal HIV subjects (p = 0.02, U test). There was also a trend for increasing cortical FKBP51 IRn with the increasing severity of HAND (p = 0.08, Kruskal-Wallis test). No significant changes in FKBP51 IRn were found with respect to hepatitis C virus infection, lifetime methamphetamine use, or antiretroviral treatment in HIV subjects. In conclusion, the increased cortical expression of FKBP51 (an inhibitor for GR activity) might represent negative feedback in an attempt to reduce GR sensitivity in the setting of chronic stress-induced elevation of GR-mediated signaling inherent in HIV infection. The further increased FKBP51 expression might lead to maladaptive stress response and HAND.

Autopsy findings after intracranial thrombectomy for acute ischemic stroke: a clinicopathologic study of 5 patients.

BACKGROUND AND PURPOSE: Endovascular thrombectomy is an increasingly used treatment for arterial occlusion in acute stroke. Various devices (including most extensively the Mechanical Embolus Removal in Cerebral Ischemia [MERCI] Retriever device) have been used for this. METHODS: We review the neuropathologic findings in 5 patients (age range, 59 to 87 years) who died acutely or as late as 38 days after procedures using the MERCI (4 patients) and Penumbra (1 patient) devices were carried out to remove thromboemboli from the middle cerebral artery. Partial recanalization was achieved by thrombectomy in all 5 patients. RESULTS: All patients showed extensive cerebral infarcts, 3 of 5 with clinical hemorrhagic transformations of the infarct or frank intraparenchymal hemorrhage after thrombectomy; in 1 case, this was judged to be at least partly on the basis of concomitant hypertensive microvascular disease. With 1 exception, basal arteries examined in detail by immunohistochemistry showed prominent, although usually nonocclusive (and generally nonulcerated), atheromata, often with significant luminal stenosis. One patient showed a subintimal dissection with resultant occlusion of the middle cerebral artery. CONCLUSIONS: In this highly selected group of patients, the vascular pathological abnormalities affecting basal arteries were variable, but complicated atherosclerosis was a common finding. Extensive irreversible brain necrosis before therapeutic procedures may have contributed to deaths.