Watch brain circulation in unexplained progressive myelopathy: a review of Cognard type V arterio-venous fistulas.

BACKGROUND: Intracranial dural arterio-venous fistulas are pathological anastomoses between arteries and veins located within dural sheets and whose clinical manifestations depend on location and hemodynamic features. They can sometimes display perimedullary venous drainage (Cognard type V fistulas-CVFs) and present as a progressive myelopathy. Our review aims at describing CVFs' variety of clinical presentation, investigating a possible association between diagnostic delay and outcome and assessing whether there is a correlation between clinical and/or radiological signs and clinical outcomes. METHODS: We conducted a systematic search on Pubmed, looking for articles describing patients with CVFs complicated with myelopathy. RESULTS: A total of 72 articles for an overall of 100 patients were selected. The mean age was 56.20 ± 14.07, 72% of patients were man, and 58% received an initial misdiagnosis. CVFs showed a progressive onset in 65% of cases, beginning with motor symptoms in 79% of cases. As for the MRI, 81% presented spinal flow voids. The median time from symptoms' onset to diagnosis was 5 months with longer delays for patients experiencing worse outcomes. Finally, 67.1% of patients showed poor outcomes while the remaining 32.9% obtained a partial-to-full recovery. CONCLUSIONS: We confirmed CVFs' broad clinical spectrum of presentation and found that the outcome is not associated with the severity of the clinical picture at onset, but it has a negative correlation with the length of diagnostic delay. We furthermore underlined the importance of cervico-dorsal perimedullary T1/T2 flow voids as a reliable MRI parameter to orient the diagnosis and distinguish CVFs from most of their mimics.

Neurology of cancer immunotherapy.

BACKGROUND: Immunotherapy is nowadays considered a mainstay of cancer treatment, dramatically affecting the disease-free survival rate in several aggressive malignancies. Unfortunately, cancer immunotherapy can also trigger life-threatening autoimmune neurological complications named "neurological adverse effects" (NAEs). NAEs can affect both the central nervous system (CNS), as in ipilimumab-related aseptic meningitis, and the peripheral nervous system (PNS), as in nivolumab-induced myasthenia gravis. CURRENT EVIDENCE: The incidence of NAEs is highly variable, ranging from 2 to 4% using checkpoint inhibitors to 50% using blinatumomab. Looking at these numbers, it appears clear that neurologists will soon be called more and more frequently to decide upon the best therapeutic strategy for a patient receiving immunotherapy and experiencing a NAE. Most of them can be treated or reverted withholding the offending drug and adding IVIg, plasmapheresis, or steroids to the therapy. Sometimes, however, for oncological reasons, immunotherapy cannot be stopped so the neurologist needs to know what countermeasures have proven most effective. Moreover, patients with a pre-existing autoimmune neurological disease (AID), such as myasthenia gravis or multiple sclerosis, might need immunotherapy during their life, risking a severe worsening of their symptoms. In that setting, the neurologist needs to properly counsel patients about the risk of a therapy-related relapse. CONCLUSION: In this article, we describe the most frequently reported NAEs and aim to give neurologists a practical overview on how to deal with them.

SORL1 gene mutation and octapeptide repeat insertion in PRNP gene in a case presenting with rapidly progressive dementia and cerebral amyloid angiopathy.

BACKGROUND AND PURPOSE: Cerebral amyloid angiopathy (CAA) has been associated with a variety of neurodegenerative disorders, included prion diseases and Alzheimer's disease; its pathophysiology is still largely unknown. We report the case of an 80-year-old man with rapidly progressive dementia and neuroimaging features consistent with CAA carrying two genetic defects in the PRNP and SORL1 genes. METHODS: Neurological examination, brain magnetic resonance imaging (MRI), electroencephalographic-electromyographic (EEG-EMG) polygraphy, and analysis of 14-3-3 and tau proteins, Aß40, and Aß42 in the cerebrospinal fluid (CSF) were performed. The patient underwent a detailed genetic study by next generation sequencing analysis. RESULTS: The patient presented with progressive cognitive dysfunction, generalized myoclonus, and ataxia. Approximately 9 months after symptom onset, he was bed-bound, almost mute, and akinetic. Brain MRI was consistent with CAA. CSF analysis showed high levels of t-tau and p-tau, decreased Aß42, decreased Aß42/Aß40 ratio, and absence of 14.3.3 protein. EEG-EMG polygraphy demonstrated diffuse slowing, frontal theta activity, and generalized spike-waves related to upper limb myoclonus induced by intermittent photic stimulation. Genetic tests revealed the presence of the E270K variant in the SORL1 gene and the presence of a single octapeptide repeat insertion in the coding region of the PRNP gene. CONCLUSIONS: The specific pathogenic contribution of the two DNA variations is difficult to determine without neuropathology; among the possible explanations, we discuss the possibility of their link with CAA. Vascular and degenerative pathways actually interact in a synergistic way, and genetic studies may lead to more insight into pathophysiological mechanisms.

Skin Nerve Phosphorylated α-Synuclein Deposits in Parkinson Disease With Orthostatic Hypotension.

This study aimed to investigate phosphorylated α-synuclein (p-syn) in autonomic skin nerves of Parkinson disease (PD) patients with and without orthostatic hypotension (OH). We studied 28 PD patients with normal corrected Mini-Mental State Examination including 14 patients with neurogenic OH (PD + OH) and 14 matched patients did not complain of OH (PD - OH); 7 of whom were re-evaluated over a follow-up period (4 ± 2 years). Skin biopsy was performed in proximal and distal sites. PD + OH patients showed a higher p-syn deposition than PD - OH, with widespread autonomic cholinergic and adrenergic skin nerve involvement. Over the follow-up period, PD - OH patients showed an increase in motor dysfunction scores without autonomic symptoms and a slight increase of skin p-syn deposition but still lower than PD + OH, mainly restricted to adrenergic fibers of skin vessels (SV). In summary, PD + OH patients showed a wide involvement of p-syn deposits in autonomic cholinergic and adrenergic skin nerves compared with PD - OH, and PD - OH patients showed a lower load of skin p-syn restricted to adrenergic fibers of SV still persisting over the follow-up period. The data supported a different pathogenesis between PD + OH and PD - OH and may help to identify a specific diagnostic trait for PD + OH.