Adler, Charles H.

Objective: To understand the challenges to diagnosis in patients with neurogenic orthostatic hypotension (nOH) Background: nOH is a sustained reduction in blood pressure (BP) with postural change associated with autonomic dysfunction. Despite symptoms of nOH, many patients struggle to find an accurate diagnosis. Methods: An online, US-based survey designed by the authors was conducted by Harris Poll. Eligible participants were ≥18 years of age with Parkinson disease, multiple system atrophy, or pure autonomic failure and ≥1 of the following: orthostatic hypotension (OH), nOH, low BP, OH/nOH symptoms, or were caregivers of eligible participants. Results: The survey included 363 patients and 128 caregivers. Groups were separate, where caregivers were not the caregivers to patient responders. Respondents indicated that patients experienced nOH symptoms long term (Table 1) . Most patients (69%) and caregivers (59%) reported discussing nOH symptoms with a healthcare provider (HCP) within the first year of symptom onset, but only 36% of patients and 16% of caregivers reported a formal diagnosis of OH or nOH. Of those with a formal diagnosis, the majority of patients (50%) were frustrated by the path to diagnosis and more than 40% of patients and caregivers reported that the patient saw ≥3 HCPs before diagnosis. After diagnosis, most patients (70%) and caregivers (60%) reported improved symptom management. Conclusions: This survey reveals that patients and caregivers may find the path to nOH diagnosis challenging and suggests increased awareness among HCPs is needed. Once a diagnosis is made nOH symptoms are better managed.

Recent reports have suggested a high prevalence of olfactory bulb synucleinopathy in Lewy body disorders but there have been no estimates of the sensitivity or specificity of this as a diagnostic test. We performed α‐synuclein immunostaining on paraffin‐embedded sections of olfactory bulb from a series of neuropathologically‐diagnosed subjects from the Sun Health Research Institute Brain Donation Program/Arizona Parkinson's Disease Consortium. Included in the series were 76 normal elderly individuals, 8 subjects with incidental Lewy body disease (ILBD), 63 with Parkinson's disease (PD) and 79 with dementia with Lewy bodies (DLB). Sections were stained with a sensitive method employing pretreatment with proteinase K. The ratios of positive to negative olfactory bulb staining for each diagnostic category were: normal 5/71; ILBD 8/0; PD 57/6; DLB 74/5. An α‐synuclein‐positive olfactory bulb has 92% sensitivity and 93% specificity for the diagnosis of PD versus normal while for DLB it is 94% and 93%, respectively. As all 8 cases of ILBD had a positive olfactory bulb it appears that olfactory bulb synucleinopathy may also be a reliable marker of presymptomatic Lewy body disorders. Supported by the AZ Dept. of Health Services, NIA P30 AG19610 and the Prescott Family Initiative of the Michael J. Fox Foundation.

Background: Braak and others have proposed that Lewy-type α-synucleinopathy in Parkinson’s disease (PD) may arise from an exogenous pathogen that passes across the gastric mucosa and then is retrogradely transported up the vagus nerve to the medulla. Objective: We tested this hypothesis by immunohistochemically staining, with a method specific for p-serine 129 α-synuclein (pSyn), stomach and vagus nerve tissue from an autopsy series of 111 normal elderly subjects, 33 with incidental Lewy body disease (ILBD) and 53 with PD. Methods: Vagus nerve samples were taken adjacent to the carotid artery in the neck. Stomach samples were taken from the gastric body, midway along the greater curvature. Formalin-fixed paraffin-embedded sections were immunohistochemically stained for pSyn, shown to be highly specific and sensitive for α-synuclein pathology. Results: Median disease duration for the PD group was 13 years. In the vagus nerve none of the 111 normal subjects had pSyn in the vagus, while 12/26 ILBD (46%) and 32/36 PD (89%) subjects were pSyn-positive. In the stomach none of the 102 normal subjects had pSyn while 5/30 (17%) ILBD and 42/52 (81%) of PD subjects were pSyn-positive. Conclusion: As there was no pSyn in the vagus nerve or stomach of subjects without brain pSyn, these results support initiation of pSyn in the brain. The presence of pSyn in the vagus nerve and stomach of a subset of ILBD cases indicates that synucleinopathy within the peripheral nervous system may occur, within a subset of individuals, at preclinical stages of Lewy body disease.

Background Patients with restless legs syndrome (RLS) have increased silent microvascular disease by magnetic resonance imaging. However, there has been no previous autopsy confirmation of these magnetic resonance imaging findings. RLS is also frequently associated with inflammatory and immunologically mediated medical disorders. The postmortem cortex in patients with RLS was therefore evaluated for evidence of microvascular and immunological changes. Methods and Results Ten microvascular injury samples of precentral gyrus in 5 patients with RLS (3 men, 2 women; mean age, 81 years) and 9 controls (2 men, 7 women; mean age, 90 years) were studied by hematoxylin and eosin stains in a blinded fashion. None of the subjects had a history of stroke or neurologic insults. In a similar manner, the following immunohistochemistry stains were performed: (1) glial fibrillary acidic protein (representing gliosis, reactive change of glial cells in response to damage); (2) CD3 (a T‐cell marker); (3) CD19 (a B‐cell marker); (4) CD68 (a macrophage marker); and (5) CD117 (a mast cell marker). Patients with RLS had significantly greater silent microvascular disease ( P =0.015) and gliosis ( P =0.003). T cells were increased in RLS compared with controls ( P =0.009) and tended to colocalize with microvascular disease ( P =0.003). Other markers did not differ. There was no correlation between microvascular lesion load and RLS severity or duration. Conclusions Patients with RLS had statistically significantly more silent cerebral microvascular disease and gliosis than controls compatible with previous magnetic resonance imaging studies and with studies showing a link between RLS and hypertension, clinical stroke, and cardiovascular disease. T‐cell invasion may be a secondary phenomenon.

AbstractBackgroundHyposmia is characteristic of idiopathic Parkinson's disease (PD) and dementia with Lewy bodies (DLBs), whereas progressive supranuclear palsy (PSP) typically has normal sense of smell. However, there is a lack of pathologically confirmed data.ObjectiveThe objective is to study hyposmia in pathologically confirmed PSP patients and compare to PD patients and nondegenerative controls.MethodsWe studied autopsied subjects in the Arizona Study of Aging and Neurodegenerative Disorders who had antemortem olfactory testing and a neuropathological diagnosis of either PD, PSP, or control.Results: This study included 281 cases. Those with neuropathologically confirmed PSP (N = 24) and controls (N = 174) had significantly better sense of smell than those with PD (N = 76). Although most PSP patients had normal olfaction, there were some with hyposmia, resulting in an overall reduced sense of smell in PSP compared to controls. The sensitivity of having PSP pathologically in those presenting with parkinsonism and normosmia was 93.4% with a specificity of 64.7%. Cases with both PSP and PD pathologically had reduced sense of smell similar to PD alone (N = 7). Hyposmic PSP patients had significantly higher Lewy body burden not meeting criteria for additional PD/DLB diagnosis.ConclusionsPathologically confirmed PD had reduced olfaction compared with PSP or controls. In the setting of parkinsonism in this sample, the presence of normosmia had high sensitivity for PSP. Hyposmia in PSP suggests the presence of additional Lewy body pathology. © 2021 International Parkinson and Movement Disorder Society

Background: Imaging biomarkers have the potential to distinguish between different brain pathologies based on the type of ligand used with PET. AV-45 PET (florbetapir, Amyvid™) is selective for the neuritic plaque amyloid of Alzheimer’s disease (AD), while AV-133 PET (florbenazine) is selective for VMAT2, which is a dopaminergic marker. Objective: To report the clinical, AV-133 PET, AV-45 PET, and neuropathological findings of three clinically diagnosed dementia patients who were part of the Avid Radiopharmaceuticals AV133-B03 study as well as the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND). Methods: Three subjects who had PET imaging with both AV-133 and AV-45 as well as a standardized neuropathological assessment were included. The final clinical, PET scan, and neuropathological diagnoses were compared. Results: The clinical and neuropathological diagnoses were made blinded to PET scan results. The first subject had a clinical diagnosis of dementia with Lewy bodies (DLB); AV-133 PET showed bilateral striatal dopaminergic degeneration, and AV-45 PET was positive for amyloid. The final clinicopathological diagnosis was DLB and AD. The second subject was diagnosed clinically with probable AD; AV-45 PET was positive for amyloid, while striatal AV-133 PET was normal. The final clinicopathological diagnosis was DLB and AD. The third subject had a clinical diagnosis of DLB. Her AV-45 PET was positive for amyloid and striatal AV-133 showed dopaminergic degeneration. The final clinicopathological diagnosis was multiple system atrophy and AD. Conclusion: PET imaging using AV-133 for the assessment of striatal VMAT2 density may help distinguish between AD and DLB. However, some cases of DLB with less-pronounced nigrostriatal dopaminergic neuronal loss may be missed.

AbstractBackgroundPost‐mortem assessment remains the only option and a gold standard for a definitive diagnosis of Parkinson’s disease (PD). The antemortem diagnosis is challenging due to a variable clinical presentation and the abundance of mimicking conditions, obscuring the clinical picture and delaying the treatment. It is well established that while PD pathologically manifests in central nervous system with aggregation of α‐synuclein as Lewy bodies and Lewy neurites, this pathology is also found in the peripheral nervous system. Peripheral Lewy‐type synucleinopathy (LTS) is present in early PD, suggesting its utility as a diagnostic and prognostic biomarker. We have previously confirmed that detection of LTS in submandibular gland (SMG) biopsies is sensitive (.75) and specific (.90) for early PD. However, the assessment by a neuropathologist of multiple levels of such biopsy is laborious and time‐consuming.MethodHere work we applied two Convolutional Neural Networks (CNN) for detection of LTS on 283 digital whole slide images (WSI) from 95 unique SMG biopsies. A total number of 8,386 LTS were annotated following the interrater reliability study with kappa=.7. We used transfer learning to train a CNN model to classify image patches (40‐by‐40 pixels at 20x) with and without presence of LTS objects.ResultThe trained CNNs showed the following performance on image patches: sensitivity: .982/.988, specificity: .998/.999, precision: .852/.950, accuracy: .995/.998, and F‐1 score .912/.968 for ResNet30/InceptionV4 respectively. On test WSI the sensitivity in detecting LTS was .963/.971 respectively.ConclusionThis work is first to demonstrate the practical utility of an CNN for screening for LTS, which can further translate into a practical screening tool facilitating the antemortem diagnosis of PD. We further plan to develop neural networks for accurate and precise detection and quantification of LTS in antemortem SMG biopsies. This, altogether, would offer a screening, confirmatory, prognostic, and quantitative tool for clinical assessment of early PD.

ABSTRACT Background An unmet clinical need in Parkinson's disease (PD) is to identify biomarkers for diagnosis, preferably in peripherally accessible tissues such as skin. Immunohistochemical studies have detected pathological α‐synuclein (αSyn) in skin biopsies from PD patients albeit sensitivity needs to be improved. Objective Our study provides the ultrasensitive detection of pathological αSyn present in the skin of PD patients, and thus, pathological αSyn in skin could be a potential biomarker for PD. Methods The real‐time quaking‐induced conversion assay was used to detect pathological αSyn present in human skin tissues. Further, we optimized this ultra‐sensitive and specific assay for both frozen and formalin‐fixed paraffin‐embedded sections of skin tissues. We determined the seeding kinetics of the αSyn present in the skin from autopsied subjects consisting of frozen skin tissues from 25 PD and 25 controls and formalin‐fixed paraffin‐embedded skin sections from 12 PD and 12 controls. Results In a blinded study of skin tissues from autopsied subjects, we correctly identified 24/25 PD and 24/25 controls using frozen skin tissues (96% sensitivity and 96% specificity) compared to 9/12 PD and 10/12 controls using formalin‐fixed paraffin‐embedded skin sections (75% sensitivity and 83% specificity). Conclusions Our blinded study results clearly demonstrate the feasibility of using skin tissues for clinical diagnosis of PD by detecting pathological αSyn. Moreover, this peripheral biomarker discovery study may have broader translational value in detecting misfolded proteins in skin samples as a longitudinal progression marker. © 2020 International Parkinson and Movement Disorder Society