[Clinical and electrophysiological characteristics and treatment outcomes of anti-neutrophil cytoplasmic antibody ANCA-associated vasculitic neuropathy].

Objective: To investigate the clinical and electrophysiological characteristics of ANCA-associated vasculitic neuropathy (VN) and analyze the predictors of treatment outcomes. Methods: Retrospective case series. In all, 652 consecutive patients with ANCA-associated vasculitis were admitted to the First Medical Center of the Chinese PLA General Hospital between January 2006 and December 2022. Peripheral neuropathy occurred in 91 patients. Patients were excluded if other known causes of neuropathy were present. Sixty-one patients were eventually enrolled, including 17 with eosinophilic granulomatosis with polyangiitis (EGPA), 11 with granulomatosis polyangiitis (GPA), and 33 with microscopic polyangiitis (MPA). Their clinical data were collected and clinical characteristics, VN manifestations, electrophysiological findings (including interside amplitude ratio [IAR]), and treatment outcomes were compared among the three subsets of AAV. Then, factors influencing the treatment outcomes were analyzed using multivariable logistic regression analysis. Results: Peripheral neuropathy occurred in 62.1%(18/29) of EGPA, 8.3%(15/180) of GPA, and 13.1%(58/443) of MPA patients. The age at onset and examination was higher in patients with MPA than those with EGPA or GPA (P<0.01). The occurrence of VN was later in patients with GPA than those with EGPA (P<0.01), and the GPA group had fewer affected nerves than the other two groups (P<0.016). The abnormal IARs of motor nerves in lower limbs were more detected in the EGPA than the MPA group (P<0.01). Logistic regression analysis suggested that higher Birmingham vasculitis activity score-version 3 (BVAS-V3) (OR=6.85, 95%CI 1.33-35.30) was associated with better treatment outcomes of VN. However, central nervous system involvement was a risk factor for poor treatment outcomes (OR=0.13, 95%CI 0.02-0.89). Conclusions: The clinical and electrophysiological characteristics of VN were slightly different among subsets of AAV. Patients with GPA often presented with polyneuropathy and had fewer nerves affected; mononeuritis multiplex was more common in EGPA than GPA and MPA. Higher BVAS-V3 and central nervous system involvement might predict the treatment outcome of VN.

Posterior Interosseous Neuropathy with Peripheral Dystonia: A Case Report.

Background: Posterior interosseous neuropathy is an uncommon cause of peripheral dystonia. Case Report: A 62-year-old man awakened and noticed right finger drop. A neurological examination revealed posterior interosseous neuropathy with dystonia-like finger movements. Abnormal movements were predominantly observed in the right thumb, ring finger, and little finger. Within 2 weeks, the muscle weakness in the right fingers had completely improved. However, a brief abnormal posture of the right thumb was persistent. Discussion: The residual abnormal posture of the right thumb may reflect pre-existing motor control abnormalities, which may have contributed to the onset of posterior interosseous neuropathy-associated peripheral dystonia.

Microvascular burden and long-term risk of stroke and dementia in type 2 diabetes mellitus.

OBJECTIVE: To examine the associations between microvascular disease (MVD) and risk of stroke, dementia, and their major subtypes among individuals with type 2 diabetes mellitus (T2DM). METHODS: We included 26,173 participants with T2DM from the UK Biobank who had no known stroke or dementia at baseline. MVD burden was reflected by the presence of retinopathy, peripheral neuropathy, and chronic kidney disease. Cox regression models were used to estimate hazard ratios (HRs) and 95 % confidential intervals (CIs) of stroke and dementia associated with overall MVD burden and individual MVD. RESULTS: During a median follow-up of 11.5 years, 1103 incident stroke (964 ischemic and 269 hemorrhagic stroke) and 813 incident dementia (312 Alzheimer's disease and 304 vascular dementia) cases were identified. The risk of stroke, dementia, and their major subtypes all increased with an increasing number of MVD (all P-trend <0.001). The adjusted HRs (95 % CIs) comparing three with no MVD were 5.03 (3.16, 8.02) for all stroke, 4.57 (2.75, 7.59) for ischemic stroke, and 6.60 (2.65, 16.43) for hemorrhagic stroke. The corresponding estimates were 4.28 (2.33, 7.86) for all-cause dementia, 6.96 (3.02, 16.01) for Alzheimer's disease, and 3.81 (1.40, 10.42) for vascular dementia. Among the three MVD, chronic kidney disease showed the strongest associations with both stroke subtypes, while peripheral neuropathy was most strongly associated with both dementia subtypes. CONCLUSIONS: Risk of stroke, dementia, and their major subtypes increased with an increasing number of MVD. The associations of individual MVD with stroke and dementia varied substantially by types of MVD.

[Role and place of ipidacrine in the therapy of diseases of the peripheral nervous system. The resolution of the expert council]. / Rol' i mesto ipidakrina v terapii zabolevanii perifericheskoi nervnoi sistemy. Rezolyutsiya Soveta ekspertov.

The resolution of the expert council is devoted to discussing aspects of the use of ipidacrine for the treatment of mononeuropathies, polyneuropathies and radiculopathies of various etiologies. Specialists prepared recommendations for ipidacrine's application in treating peripheral nervous system disorders.

CGRP sensory neurons promote tissue healing via neutrophils and macrophages.

The immune system has a critical role in orchestrating tissue healing. As a result, regenerative strategies that control immune components have proved effective1,2. This is particularly relevant when immune dysregulation that results from conditions such as diabetes or advanced age impairs tissue healing following injury2,3. Nociceptive sensory neurons have a crucial role as immunoregulators and exert both protective and harmful effects depending on the context4-12. However, how neuro-immune interactions affect tissue repair and regeneration following acute injury is unclear. Here we show that ablation of the NaV1.8 nociceptor impairs skin wound repair and muscle regeneration after acute tissue injury. Nociceptor endings grow into injured skin and muscle tissues and signal to immune cells through the neuropeptide calcitonin gene-related peptide (CGRP) during the healing process. CGRP acts via receptor activity-modifying protein 1 (RAMP1) on neutrophils, monocytes and macrophages to inhibit recruitment, accelerate death, enhance efferocytosis and polarize macrophages towards a pro-repair phenotype. The effects of CGRP on neutrophils and macrophages are mediated via thrombospondin-1 release and its subsequent autocrine and/or paracrine effects. In mice without nociceptors and diabetic mice with peripheral neuropathies, delivery of an engineered version of CGRP accelerated wound healing and promoted muscle regeneration. Harnessing neuro-immune interactions has potential to treat non-healing tissues in which dysregulated neuro-immune interactions impair tissue healing.

Association of Risk Factors and Comorbidities With Chronic Pain in the Elderly Population.

INTRODUCTION/OBJECTIVE: Chronic pain disorders affect about 20% of adults in the United States, and it disproportionately affects individuals living in the neighborhoods of extreme socioeconomic disadvantage. In many instances, chronic pain has been noted to arise from an aggregation of multiple risk factors and events. Therefore, it is of importance to recognize the modifiable risk factors. The aim of this study was to investigate the comorbid medical conditions and risk factors associated with chronic pain disorders in patients aged 65 years and older. METHODS: Our team retrospectively reviewed medical records of elderly patients (65 years and older) who were evaluated in our outpatient medicine office between July 1, 2020 and June 30, 2021 for acute problems, management of chronic medical problems, or well visits. We divided our patients into a group who suffered from chronic pain disorder, and another group who did not have chronic pain disorder. The association of variables were compared between those groups. RESULTS: Of the 2431 patients, 493 (20.3%) had a chronic pain disorder. A higher frequency of females in the group with chronic pain disorder was found compared to the group without a chronic pain disorder (60.6% vs 55.2%; P = .033). The mean ages between the two groups were similar in the group with a chronic pain disorder compared to the group without (76.35 ± 7.5 year vs 76.81 ± 7.59 year; P = .228). There were significant associations of certain comorbidities in the group with a chronic pain disorder compared to the group without a chronic pain disorder, such as depression (21.9% vs 15.2%; P < .001), anxiety (27.0% vs 17.1%; P < .001), chronic obstructive pulmonary disease (8.7% vs 6.1%; P = .036), obstructive sleep apnea (16.8% vs 11.6%; P = .002), gastroesophageal reflux disease (40.8% vs 29.0%; P < .001), osteoarthritis (49.3% vs 26.1%; P < .001), other rheumatologic diseases (24.9% vs 19.4%; P = .006), and peripheral neuropathy (14.4% vs 5.3%; P < .001). CONCLUSION: Female sex, depression, anxiety, chronic obstructive pulmonary disease, obstructive sleep apnea, gastroesophageal reflux disease, osteoarthritis, other rheumatologic diseases, and peripheral neuropathy were significantly associated with chronic pain disorder in elderly patients, while BMI was not associated with chronic pain disorder.

Clinical and laboratory findings in scrub typhus associated Guillain-Barré syndrome in South Korea.

BACKGROUND AND AIMS: Scrub typhus is an endemic disease in the fall season that occurs in a limited number of places known as the Tsutsugamushi Triangle. Peripheral neuropathy is a common complication of scrub typhus. Herein, we encountered several patients with ascending paralysis after scrub typhus infection, who were diagnosed with Guillain-Barré syndrome (GBS). We aimed to investigate the clinical and laboratory characteristics of patients who developed GBS after scrub typhus. METHODS: Patients were retrospectively recruited from six nationwide tertiary centers in South Korea from January 2017 to December 2021. Patients who had been clinically diagnosed with GBS and confirmed to have scrub typhus via laboratory examination and/or the presence of an eschar before the onset of acute limb paralysis were included. The GBS-associated clinical and electrophysiological characteristics, outcomes, and scrub typhus-associated features were collected. RESULTS: Of the seven enrolled patients, six were female and one was male. The median time from scrub typhus infection to the onset of limb weakness was 6 (range: 2-14) days. All patients had eschar on their bodies. Four patients (57.1%) were admitted to the intensive care unit and received artificial ventilation for respiratory distress. At 6 months, the median GBS disability score was 2 (range, 1-4) points. INTERPRETATION: Patients with scrub typhus-associated GBS have a severe clinical presentation and require intensive treatment with additional immunotherapies. Therefore, GBS should be included in the differential diagnosis when peripheral neuropathies develop during scrub typhus treatment. Notably, scrub typhus is associated to GBS.

A rare case of adult-onset spastic paraparesis associated with Klinefelter syndrome.

REPORT: The rare association of Klinefelter syndrome and the clinical presentation of a late onset chronic progressive spastic paresis. CLINICAL PRESENTATION AND GENETICS: An infertile, 61-year-old man, presented with late adult onset of gait problems, deep muscle pain, and bladder problems. He presented for the first time, years after onset with a spastic paraparesis with high arched feet. His parents had already died, but the patient described high arched feet with his mother. There is no further certain information about the parents. After thorough investigation, an additional X chromosome was found, whereafter the diagnosis of Klinefelter syndrome could be made. Other acquired and genetic causes for spastic paraparesis or hereditary motor neuropathy are excluded. CONCLUSION: This rare case, together with three other literature reports by Sasaki (Intern Med 58(3):437-440, 2019), Sajra (Med Arh 61(1):52-53, 2007) and Matsubara et al., (J Neurol Neurosurg Psychiatry 57(5):640-642, 1994). suggests that Klinefelter syndrome can be associated with spastic paraparesis, besides the other various neuropsychiatric symptoms that are more commonly described.

Autoreactive T cells target peripheral nerves in Guillain-Barré syndrome.

Guillain-Barré syndrome (GBS) is a rare heterogenous disorder of the peripheral nervous system, which is usually triggered by a preceding infection, and causes a potentially life-threatening progressive muscle weakness1. Although GBS is considered an autoimmune disease, the mechanisms that underlie its distinct clinical subtypes remain largely unknown. Here, by combining in vitro T cell screening, single-cell RNA sequencing and T cell receptor (TCR) sequencing, we identify autoreactive memory CD4+ cells, that show a cytotoxic T helper 1 (TH1)-like phenotype, and rare CD8+ T cells that target myelin antigens of the peripheral nerves in patients with the demyelinating disease variant. We characterized more than 1,000 autoreactive single T cell clones, which revealed a polyclonal TCR repertoire, short CDR3ß lengths, preferential HLA-DR restrictions and recognition of immunodominant epitopes. We found that autoreactive TCRß clonotypes were expanded in the blood of the same patient at distinct disease stages and, notably, that they were shared in the blood and the cerebrospinal fluid across different patients with GBS, but not in control individuals. Finally, we identified myelin-reactive T cells in the nerve biopsy from one patient, which indicates that these cells contribute directly to disease pathophysiology. Collectively, our data provide clear evidence of autoreactive T cell immunity in a subset of patients with GBS, and open new perspectives in the field of inflammatory peripheral neuropathies, with potential impact for biomedical applications.

Neurological Manifestations Induced by Nitrous Oxide Abuse: A Case Series and Review of Literature.

INTRODUCTION: Nitrous oxide (NO) abuse is increasing among young people. This can result in severe neurological disorders such as myelopathy and/or peripheral neuropathy. We report the clinical presentations, biological, radiologic and electrophysiological findings of 5 patients hospitalized with neurological symptoms consecutive to NO abuse. In addition, a literature review was conducted to describe the neurological characteristics and to identify factors associated with a poor recovery. CASE REPORT: Among the 5 patients included, 2 had a myeloneuropathy, 2 had a sensorimotor neuropathy, and 1 had a normal spinal cord magnetic resonance imaging and electromyography despite neurological manifestations consistent with myeloneuropathy. After vitamin B 12 supplementation, recovery was reported in 4 patients, and 1 was lost to follow-up.From the literature review, 154 patients were included [94 males; median age 22 (19 to 26) y; NO exposure 9 (3 to 18) mo]. A myelopathy was identified in 116 patients (75%) and a peripheral neuropathy was documented in 89 patients (58%). Compared with patients who recovered, those with sequelae were more likely to have a motor deficit at presentation ( P <0.001), to use NO regularly ( P <0.001), to have a lower vitamin B 12 level ( P =0.04), and a higher concentration of homocysteine ( P =0.04). A less extensive myelopathy was more frequently found in the group with favorable outcomes ( P =0.002). CONCLUSION: Neurological disorders caused by NO may be challenging with severe clinical patterns. We identified several factors associated with a poor recovery, to make clinicians aware of NO-induced neurotoxicity.

Thiamine deficiency-related neuropathy: A reversible entity from an endemic area.

BACKGROUND AND PURPOSE: Despite thiamine deficiency being a lesser-known entity in modern times, beriberi in various forms, including thiamine deficiency-related neuropathy, remains endemic in Kashmir due to the consumption of polished rice as a staple food. This observational study investigates cases of peripheral neuropathy of unknown etiology and their potential responsiveness to thiamine administration. METHODS: This prospective study enrolled adult patients presenting to the emergency department with weakness consistent with thiamine deficiency-related neuropathy and conducted a therapeutic challenge with thiamine on 41 patients. Response to thiamine therapy was monitored based on subjective and objective improvements in weakness and power. Patients were divided into thiamine responders (n = 25) and nonresponders (n = 16) based on their response to thiamine therapy and nerve conduction studies. RESULTS: Most of the baseline characteristics were similar between responders and nonresponders, except the responders exhibited lower thiamine levels and higher partial pressure of oxygen and lactate levels compared to nonresponders. All patients had a history of consuming polished rice and traditional salt tea. Although weakness in the lower limbs was present in both groups, nonresponders were more likely to exhibit weakness in all four limbs. Clinical improvement was observed within 24 h, but proximal muscle weakness persisted for an extended period of time. CONCLUSIONS: Thiamine deficiency-related neuropathy presents with predominant lower limb weakness, exacerbated by vomiting, poor food intake, psychiatric illness, and pregnancy. Thiamine challenge should be followed by observation of clinical and biochemical response.

Burn Injury-related Growth Factor Expressions and Their Potential Roles in Burn-related Neuropathies.

In the context of burn injury, growth factors (GFs) play a significant role in mediating the complex local and systematic processes that occur. Among the many systemic complications that arise following a burn injury, peripheral neuropathy remains one of the most common. Despite the broad understanding of the effects GFs have on multiple tissues, their potential implications in both wound healing and neuropathy remain largely unexplored. Therefore, this review aims to investigate the expression patterns of GFs prominent during the burn wound healing process and explore the potential contributions these GFs have on the development of burn-related peripheral neuropathy.

Feasibility of using the NewGait assistive device for correcting gait deviations in individuals with various neurological disorders: Case study.

PURPOSE: Impaired gait is one of the earliest, most devastating, and long-lasting symptoms associated with neurological disorders. This study tested the feasibility of wearing the NewGait rehabilitative device in individuals with gait impairments due to the most common neurological disorders. METHODS: Seven participants with gait impairments due to strokes, Multiple Sclerosis, peripheral neuropathies, Cerebral Palsy (CP) and Parkinson's Disease (PD) were included in the study. Their walking with and without wearing the NewGait was analyzed and compared using the Vicon T160 system for motion analysis. Gait velocity, step length, foot clearance, lateral displacement of the Center of Mass, gait deviation and symmetry indexes were compared using two standard deviation band method for each participant. RESULTS: Participants subjectively assessed the NewGait as a comfortable device to wear and showed immediate gait improvements to varying degrees. Most improvements were observed in participants with muscle weakness due to peripheral neuropathies, stroke, MS, and CP. These participants improved their foot clearance, gait velocity, and step length. Participants with cerebellar stroke and PD increased their gait stability. All participants demonstrated a reduction in composite gait deviation indexes. Not all gait parameters, though, showed immediate changes. CONCLUSION: The results suggest that the NewGait rehabilitative device is feasible and useful for correcting gait impairments caused by neurological deficits. Participants may need to wear this device for longer periods of time in order to achieve long lasting changes in the gait pattern, rather than an immediate correction.

Wound complication risk factors following open reduction and internal fixation of ankle fractures.

This study was designed to identify risk factors for wound complications including surgical site infection (SSI) and wound healing issues following open reduction and internal fixation (ORIF) of ankle fractures. A retrospective analysis of individuals with ankle fractures treated with ORIF was undertaken. Study subjects were divided into a wound complications (WC) group and a no wound complication (NWC) group. The WC group was further divided into an SSI group and wound healing issues group. Twenty-one potential risk factors associated with wound complications after ORIF were tracked. Uni- and multivariate binary logistical regression analyses were used to identify risk factors associated with wound complications, ISS and wound healing issues. In total, 613 individuals, who had undergone surgery for ankle fractures formed the study cohort. The incidence of postoperative wound complications was 10.3% (63 cases), including 5.2% of SSI (32 cases) and 5.1% of wound healing issues (31 cases). The independent risk factors for wound complications were age 65 years or older, preoperative serum albumin level below 35 g/L, peripheral neuropathy, open fracture, fewer than seven cases per year in surgical volume, and attending surgeon level. The independent risk factors for SSI were age 65 years or older, preoperative serum albumin level below 35 g/L, open fracture and fewer than seven cases per year in surgical volume. The independent risk factors for wound healing issues were preoperative serum albumin level below 35 g/L, peripheral neuropathy, open fracture and attending surgeon level. Herein we found both factors inherent to the injury and individual and those pertaining to the surgical team affected the frequency of wound complications after ORIF of ankle fractures. Specifically, advanced age and low surgical volume were associated with a greater risk of SSI. Peripheral neuropathy and the low expertise level on the part of the surgeon were associated with a greater risk of wound healing issues. Hypoproteinaemia and open fracture were both associated with a greater risk of both SSI and wound healing issues.

Ramen noodle neuropathy: an atypical case of partial paralysis from malnutrition.

INTRODUCTION: Due to a COVID-related job loss resulting in financial and food insecurity, a 28-year-old woman initiated a diet consisting solely of one cup of ramen noodles daily for twenty-two months, leading to 27 kg of weight loss. Ramen noodles are low in calories and lack key nutrients, including potassium, chloride, and vitamin B12. CASE DESCRIPTION: The patient presented to the emergency department with acute, worsening weakness and paresthesias in her left wrist and hand. Exam revealed no other abnormalities aside from a cachectic appearance. Labs revealed marked hypokalemia, hypochloremia, lactic acidosis, a mixed metabolic alkalosis with respiratory acidosis, and low levels of zinc and copper. An EKG revealed a prolonged QT interval. After a neurology and psychiatry consult, the patient was admitted for failure to thrive with malnutrition, peripheral neuropathy, hypokalemia, and an acid-base disorder. An MRI of the brain was unremarkable. Studies of other nutritional deficiencies, autoimmune conditions, and sexually transmitted infections were unremarkable. The patient received food and vitamin supplementation, was monitored for re-feeding syndrome, and had a significant recovery. DISCUSSION: After stroke, spinal injury, multiple sclerosis, and the most common focal mononeuropathies were ruled out, the clinical focus turned to nutritional deficiencies, the most significant of which was hypokalemia. Prior research has shown that severe hypokalemia can lead to weakness. It has also shown that chronically insufficient dietary intake is a common cause of hypokalemia. This case, with its partial paralysis of a unilateral upper extremity, may add to the known clinical manifestations of hypokalemia. We review the role of hypokalemia and hypochloremia in acid-base dynamics. Etiologies and clinical manifestations of cobalamin, thiamine, pyridoxine, and copper deficiencies, along with lead toxicity, are also discussed. Diagnostic clarity of mononeuropathies in the context of malnutrition and hypokalemia can be aided by urine potassium levels prior to repletion, neuroimaging that includes the cervical spine, and follow-up electromyography.

Heavy metal worker's pneumonoconiosis with lung parenchymal damage and Peripheral neuropathy: case report.

Heavy metals even at low concentrations can damage all systems in the human body from the cellular level by causing disruptions in DNA repair mechanisms, cell division and apoptosis. A 49-year-old man who had been working in the sanding and deburring department of a factory producing underground water pipes for 15 years, presented with complaints of effort dyspnea, cough and loss of strength in his left hand. Computed tomography of the lung revealed diffuse micronodular appearance in all zones in both lungs, subpleural nodule and bronchial dilatation. All serological tests for autoimmune disease were negative. Neurological examination of the patient revealed signs of 2nd motor neuron involvement only in one upper extremity. All of the tests that were studied for the differential diagnosis of multifocal motor neuropathy were found negative. Open lung biopsy with videothoracoscopy was practiced and interstitial changes were observed in the lung parenchyma with intense iron accumulation with Prussian blue stain. The patient was diagnosed with hard metal lung disease (HMLD) and toxic neuropathy (TN) with peripheral nerve involvement due to exposure to metal dust in the working environment. Although the patient had no loss of lung function, he was removed from the working environment, because of function loss in the left hand and is still being followed up.

Cell Therapy of Vascular and Neuropathic Complications of Diabetes: Can We Avoid Limb Amputation?

Globally, a leg is amputated approximately every 30 seconds, with an estimated 85 percent of these amputations being attributed to complications arising from diabetic foot ulcers (DFU), as stated by the American Diabetes Association. Peripheral arterial disease (PAD) is a risk factor resulting in DFU and can, either independently or in conjunction with diabetes, lead to recurring, slow-healing ulcers and amputations. According to guidelines amputation is the recommended treatment for patients with no-option critical ischemia of the limb (CTLI). In this article we propose cell therapy as an alternative strategy for those patients. We also suggest the optimal time-frame for an effective therapy, such as implanting autologous mononuclear cells (MNCs), autologous and allogeneic mesenchymal stromal cells (MSC) as these treatments induce neuropathy relief, regeneration of the blood vessels and tissues, with accelerated ulcer healing, with no serious side effects, proving that advanced therapy medicinal product (ATMPs) application is safe and effective and, hence, can significantly prevent limb amputation.

Effects of body weight variability on risks of macro- and microvascular outcomes in individuals with type 2 diabetes: The Rio de Janeiro type 2 diabetes cohort.

AIMS: To investigate the effects of body weight variability (BWV) on macro- and microvascular outcomes in a type 2 diabetes cohort. METHODS: BWV parameters were assessed in 684 individuals. Multivariable Cox regressions examined associations between BWV parameters and cardiovascular outcomes (total cardiovascular events [CVEs], major CVEs [MACEs], cardiovascular deaths),all-cause mortality and microvascular outcomes. Interaction/subgroup analyses were performed according to being physically-active/sedentary and having/not lost ≥ 5 % of weight. RESULTS: Median follow-up was 11 years over which 194 total CVEs (174 MACEs), and 223 all-cause deaths (110 cardiovascular), occurred. There were 215 renal, 152 retinopathy and 167 peripheral neuropathy development/worsening outcomes. In general, increased BWV was associated with higher risks of CVEs, MACEs, all-cause mortality, advanced renal failure and peripheral neuropathy outcomes, but not of microalbuminuria and retinopathy outcomes. On interaction/subgroup analyses, increased BWV was associated with higher risks of outcomes in sedentary individuals and in those who did not lose ≥ 5 % of body weight. In physically-active participants or in those who lost ≥ 5 % weight, the adjusted risks were null or protective. CONCLUSIONS: Increased BWV was associated with most adverse outcomes; however, in those who were physically-active or consistently losing weight, it was not hazardous and might be even beneficial.

Autoimmune Axonal Neuropathies.

OBJECTIVE: This article reviews autoimmune axonal neuropathies, their characteristic clinical features, disease and antibody associations, appropriate ancillary testing, treatment, and prognosis. LATEST DEVELOPMENTS: In 2021, the American College of Rheumatology and the Vasculitis Foundation released new summary guidelines for the treatment of antineutrophil cytoplasmic autoantibody-associated vasculitides. In addition, novel autoantibodies have been recently identified; they are often paraneoplastic and associated with axonal neuropathies. ESSENTIAL POINTS: Recognition of autoimmune axonal neuropathies is important because of the potential for effective treatment to either reverse deficits or slow the progression of disease. It is necessary to properly assess for associations with other systemic disorders (eg, systemic vasculitis, connective tissue disease, neoplasm) so that adequate treatment for both neurologic and non-neurologic aspects of the disease can be initiated.

Nutritional peripheral neuropathies.

Nutritional peripheral neuropathies are a global problem, heavily influenced by geopolitical, cultural and socioeconomic factors. Peripheral neuropathy occurs most frequently secondary to B-vitamin deficiencies, which is suspected to increase in years to come due to the popularity of vegan and vegetarian diets and increased use of bariatric surgery.This review will focus on the common B-vitamins for which a causal link to peripheral neuropathy is more established (vitamins B1, B2, B6, B9 and B12). We will review the historical human and animal data on which much of the clinical descriptions of vitamin deficiencies are based and summarise current available tools for accurately diagnosing a nutritional deficiency. We will also review recently described genetic diseases due to pathogenic variants in genes involved in B-vitamin metabolism that have helped to inform the phenotypes and potential causality of certain B-vitamins in peripheral neuropathy (B2 and B9).Endemic outbreaks of peripheral neuropathy over the last two centuries have been linked to food shortages and nutritional deficiency. These include outbreaks in Jamaican sugar plantation workers in the nineteenth century (Strachan's syndrome), World War two prisoners of war, Cuban endemic neuropathy and also Tanzanian endemic optic neuropathy, which remains a significant public health burden today. An improved understanding of lack of which vitamins cause peripheral neuropathy and how to identify specific deficiencies may lead to prevention of significant and irreversible disability in vulnerable populations.