Faculty Bibliography

Multiple system atrophy (MSA) is a rare neurodegenerative disorder with substantial knowledge gaps despite recent gains in basic and clinical research. In order to make further advances, concerted international collaboration is vital. In 2014, an international meeting involving leaders in the field and MSA advocacy groups was convened in Las Vegas, Nevada, to identify critical research areas where consensus and progress was needed to improve understanding, diagnosis, and treatment of the disease. Eight topic areas were defined: pathogenesis, preclinical modeling, target identification, endophenotyping, clinical measures, imaging biomarkers, nonimaging biomarkers, treatments/trial designs, and patient advocacy. For each topic area, an expert served as a working group chair and each working group developed priority-ranked research recommendations with associated timelines and pathways to reach the intended goals. In this report, each groups' recommendations are provided.

BACKGROUND:Chronic lung disease is a leading cause of premature death in patients with familial dysautonomia (FD). A significant number of patients have obstructive airway disease, yet it is not known whether this is pharmacologically reversible. METHODS:We conducted a double-blind, placebo-controlled, randomized clinical trial comparing the beta 2 agonist albuterol with the muscarinic blocker ipratropium bromide in patients homozygous for the IKBKAP founder mutation. Albuterol, ipratropium bromide, and placebo were administered on 3 separate days via nebulizer in the seated position. Airway responsiveness was evaluated using spirometry and impulse oscillometry 30 min post dose. Cardiovascular effects were evaluated by continuous monitoring of blood pressure, RR intervals, cardiac output, and systemic vascular resistance. RESULTS:A total of 14 patients completed the trial. Neither active agent had significant detrimental effects on heart rate or rhythm or blood pressure. Albuterol and ipratropium were similar in their bronchodilator effectiveness causing significant improvement in forced expiratory volume in 1-s (FEV1, p = 0.002 and p = 0.030). Impulse oscillometry measures were consistent with a reduction in total airway resistance post nebulization (resistance at 5 Hz p < 0.006). CONCLUSION/CONCLUSIONS:Airway obstruction is pharmacologically reversible in a number of patients with FD. In the short term, both albuterol and ipratropium were well tolerated and not associated with major cardiovascular adverse events.

Multiple system atrophy (MSA) may be difficult to distinguish clinically from other disorders, particularly in the early stages of the disease. An autonomic-only presentation can be indistinguishable from pure autonomic failure. Patients presenting with parkinsonism may be misdiagnosed as having Parkinson disease. Patients presenting with the cerebellar phenotype of MSA can mimic other adult-onset ataxias due to alcohol, chemotherapeutic agents, lead, lithium, and toluene, or vitamin E deficiency, as well as paraneoplastic, autoimmune, or genetic ataxias. A careful medical history and meticulous neurological examination remain the cornerstone for the accurate diagnosis of MSA. Ancillary investigations are helpful to support the diagnosis, rule out potential mimics, and define therapeutic strategies. This review summarizes diagnostic investigations useful in the differential diagnosis of patients with suspected MSA. Currently used techniques include structural and functional brain imaging, cardiac sympathetic imaging, cardiovascular autonomic testing, olfactory testing, sleep study, urological evaluation, and dysphagia and cognitive assessments. Despite advances in the diagnostic tools for MSA in recent years and the availability of consensus criteria for clinical diagnosis, the diagnostic accuracy of MSA remains sub-optimal. As other diagnostic tools emerge, including skin biopsy, retinal biomarkers, blood and cerebrospinal fluid biomarkers, and advanced genetic testing, a more accurate and earlier recognition of MSA should be possible, even in the prodromal stages. This has important implications as misdiagnosis can result in inappropriate treatment, patient and family distress, and erroneous eligibility for clinical trials of disease-modifying drugs.

OBJECTIVE:To assess vestibular function in patients with familial dysautonomia (FD), a hereditary sensory and autonomic neuropathy - caused by a mutation in the IKBKAP gene (c.2204 + 6 T>C) - and characterized by marked gait ataxia. METHODS:Cervical and vestibular evoked myogenic potentials (cVEMPs and oVEMPs) were recorded from the sternocleidomastoid (SCM) and extraocular muscles in 14 homozygous patients, 2 heterozygous patients, and 15 healthy controls during percussion of the forehead. RESULTS:cVEMP and oVEMP amplitudes were significantly lower, and peak latencies significantly delayed, in the FD patients. There were no differences in overall EMG during attempted maximal voluntary contractions of the SCM muscle, suggesting intact efferent function. The two heterozygotes with a minor haplotype missense (R696P) mutation in exon 19 of the IKBKAP gene had cVEMP responses less affected than the homozygous. CONCLUSIONS:The founder mutation in the IKBKAP gene affects the development of vestibular afferent pathways, leading to attenuated cVEMPs. SIGNIFICANCE/CONCLUSIONS:Vestibular abnormalities may contribute to the gait ataxia in FD.

BACKGROUND:Putaminal diffusivity in brain magnetic resonance diffusion-weighted imaging (DWI) is increased in patients with the parkinsonian variant of multiple system atrophy (MSA-P) compared to Parkinson disease (PD) patients. PURPOSE/OBJECTIVE:We performed a systematic review and meta-analysis to evaluate the diagnostic accuracy of DWI to distinguish MSA-P from PD. METHODS:Studies on DWI were identified through a systematic PubMed and Clarivate Analytics® Web of Science® Core Collection search. Papers were selected based on stringent inclusion criteria; minimum requirement was the inclusion of MSA-P and PD patients and documented true positive, true negative, false positive and false negative rates or overall sample size and reported sensitivity and specificity. Meta-analysis was performed using the hierarchical summary receiver operating characteristics curve approach. RESULTS:The database search yielded 1678 results of which 9 studies were deemed relevant. Diagnostic accuracy of putaminal diffusivity measurements were reported in all of these 9 studies, whereas results of other regions of interest were only reported irregularly. Therefore, a meta-analysis could only be performed for putaminal diffusivity measurements: 127 patients with MSA-P, 262 patients with PD and 70 healthy controls were included in the quantitative synthesis. The meta-analysis showed an overall sensitivity of 90% (95% confidence interval (CI): 76.7%-95.8%) and an overall specificity of 93% (95% CI: 80.0%-97.7%) to distinguish MSA-P from PD based on putaminal diffusivity. CONCLUSION/CONCLUSIONS:Putaminal diffusivity yields high sensitivity and specificity to distinguish clinically diagnosed patients with MSA-P from PD. The confidence intervals indicate substantial variability. Further multicenter studies with harmonized protocols are warranted particularly in early disease stages when clinical diagnosis is less certain.

Background: Symptoms of psychosis, including hallucinations and delusions, are relatively frequent in Parkinson disease and Lewy body dementia, particularly in patients receiving levodopa and dopamin-ergic agonists. However, the prevalence of psychosis in multiple system atrophy (MSA) is unknown. We aimed to determine the prevalence and characteristics of psychotic symptoms in patients with MSA, and factors associated with their development. Methods: Consecutive patients with probable MSA without previous history of psychiatric disorders were prospectively enrolled in a longitudinal observational study. The presence of hallucinations and delusions was determined during a standardized clinical interview and quantified with the Scale for the Assessment of Positive Symptoms in Parkinson disease (SAPS-PD). Patients also underwent full evaluation of visual acuity, cognition (Montreal Cognitive Assessment, MoCA), motor function and disease severity [United Multiple System Atrophy Rating Scale (UMSARS)]. Results: Of the 31 consecutive patients with probable MSA (17 men; mean age 64 +/- 8 years; 13 MSA-P and 14 MSA-C), 6 (19%) had positive symptoms of psychosis including delusions and/or hallucinations. All but one patient had the cerebellar phenotype of the disease (MSA-C). Auditory hallucinations occurred in 4 patients, visual hallucinations in 4, persecutory delusions in 3, and jealousy delusions in 3. No patients reported somatic or tactile hallucinations. Psychosis symptoms were extremely severe and refractory to treatment in 2 cases with MSA-C, both of whom died within 12 months of psychosis onset. Psychotic symptoms were not associated with levodopa or other antiparkinsonian medication treatment, visual acuity, cognitive score, depression score, or duration of illness. Conclusions: Psychotic symptoms occur in *20% of patients with MSA, the vast majority of whom have MSA-C. Severe refractory psychotic symptoms appear to be associated with poor prognosis (death < 1 year). Our results suggest that psychotic symptoms in MSA are unrelated to visual system abnormalities

Introduction: Patients with pure autonomic failure (PAF) typically present with symptoms of sympathetic insufficiency, with anhidrosis frequently reported. We here report an unusual patient with PAF who presented with cold-induced sweating. Methods: Case report. Results: A 73-year-old man had a 5-year history of frequent lightheadedness, dizziness and syncope on standing. He also had erectile dysfunction, nocturia, constipation, and dream reenactment. He also reported a significant increase in sweating in his torso, back, and both arms (particularly the left) induced by cold temperatures. Autonomic testing showed a supine hypertension (193/105 mmHg) with resting bradycardia (50 bpm). Blood pressure overshoot after release of the Valsalva strain was absent, indicating impaired baroreflex-mediated sympathetic activation. After 14-min of head-up tilt his blood pressure had dropped to 124/83 mmHg with a blunted increase in heart rate to 73 bpm. His norepinephrine levels failed to increase appropriately upon head-up tilt (supine 376 pg/mL; tilted 404 pg/mL), indicating a neurogenic cause for his orthostatic hypotension. Electrochemical skin conductance was reduced in palms and soles. An iodine-starch test was performed with a room temperature of 90degreeF and repeated after the temperature was decreased to 78degreeF. When the ambient temperature was reduced, the starch powder turned dark purple, more intensely in the left side, indicating the release of sweat. Conclusion: Cold-induced sweating can be a manifestation of autonomic failure. Possible mechanisms include cold-induced sudomotor supersensitivity triggered by the remaining fibers innervating the sweat glands

He who studies medicine without books sails an uncharted sea, but he who studies medicine without patients does not go to sea at all." (William Osler, Canadian physician 1849-1919) David H. Streeten was a master clinician with an astute eye for observation. His work was never far from the bedside describing patient's signs and symptoms in exquisite detail. I also never wandered far from the bedside. My favorite tools have always been a reflex hammer, an EKG and a Finapres. At their core, neurologists are observers and listeners, they love to watch and recognize human phenomenology. Thinking about the diseases I studied I realize that my interest for each of them was sparked by the encounter with an affected patient that made a big impression. They were 5 particular patients that I remember vividly. Each of them taught me something I did not know, kept me awake many nights and shaped my career. I will tell you some of their stories at the 2017's Streeten Memorial Lecture at the American Autonomic Society

Background: Allgrove syndrome (triple A syndrome) is a rare autosomal recessive disorder first described by endocrinologist Jeremy Allgrove in 1978 in two siblings with adrenal insufficiency, achalasia, and alacrima. Onset is usually within the first decade of life. Other features include adrenocorticotropic hormone (ACTH) unresponsiveness, and varying degrees of neurologic dysfunction. In 2002, mutations in the AAAS gene located on chromosome 12q13, which encodes for the nuclear pore protein ALADIN, were reported as the cause of the disease. The autonomic features of the disorder remain poorly understood with only ~ 100 cases in the literature, most of which were described before the availability of genetic testing. Methods: Case series of 2 patients with genetically confirmed Allgrove syndrome. Results: Case # 1: 9-year-old girl of East Indian descent presented with alacrima since birth. At age 6, she developed adrenal insufficiency manifesting as hyperpigmentation and fatigue. Genetic testing confirmed she was homozygous for the pathogenic variant c.1432C>T p.Arg478Ter. The patient had no achalasia and neurological exam was normal. Cardiovascular autonomic testing was normal. Case # 2: 39-year-old Hispanic woman presented with alacrima, achalasia, ACTH resistance, and sensorimotor polyneuropathy at the age of 13 years. Autonomic testing revealed adrenergic impairment with orthostatic hypotension together with cholinergic dysfunction and decreased heart rate variability. Genetic testing confirmed two heterozygous mutations: 1) Heterozygous Exon 6, R155P, base 464 CGT to CCT; 2) Heterozygous IVSC14 + 1G to A. Mutation 1 had not been previously reported. Conclusions: Allgrove syndrome is a rare pediatric-onset disorder with variable presentation. Neurological signs (autonomic dysfunction, hyperreflexia, dysarthria, ataxia, sensory impairment, weakness, cognitive deficits) and ACTH resistance may only manifest after many years or decades. As the number of genetically confirmed cases grows, there is a need to understand the autonomic phenotype, which should perhaps be considered the 4th A