Alcohol-related peripheral neuropathy: Clinico-neurophysiological characteristics and diagnostic utility of the neuropathy symptoms score and the neuropathy impairment score

Alcohol overconsumption is well known to cause damage to the peripheral nervous system, affecting both small and large nerve fibers. The aim of this descriptive study was to investigate peripheral nerve damage, and to correlate clinical, epidemiological and neurophysiological findings, in patients diagnosed with Alcohol Use Disorder (AUD). Ninety alcohol-dependent subjects on inpatient basis were enrolled in this prospective study over a 3-year period. Every subject was assessed by the Neuropathy Symptoms Score (NSS) questionnaire and the Neuropathy Impairment Score (NIS) clinical examination grading scale, followed by Nerve Conduction Studies, Quantitative Sensory Testing and Sympathetic Skin Response (SSR) testing. Peripheral neuropathy was diagnosed in 54 subjects (60%), by abnormal neurophysiological tests and presence of clinical signs or symptoms. Among them, pure large fiber neuropathy (LFN) was found in 18 subjects, pure small fiber neuropathy (SFN) in 12 subjects, and both large and small fiber neuropathy was diagnosed in 24 subjects. Using linear regression, we found that higher NSS and NIS scores correlated with lower amplitudes of the sural sensory nerve action potential and of the SSR. We also found a significant longer duration of alcohol abuse in subjects with neuropathy, using Student's t-test (p = 0.024). Additionally, applying NIS abnormal cut-off score ≥4, using ROC analysis, we predicted the majority of subjects with LFN, confirming 95.23% sensitivity and 93.75% specificity. Our study confirmed that peripheral neuropathy involving large and small nerve fibers, with a symmetrical length-dependent pattern, is common between patients with AUD and related to the duration of the disorder. We suggest that NSS and NIS scales could be used for the assessment of neuropathy in clinical practice, when the essential neurophysiological testing is not available.

Complications of Percutaneous Tendo-Achilles Lengthening for Treatment and Prevention of Diabetic Foot Ulcers: A Systematic Review

Percutaneous Achilles tendon lengthening is an effective surgical procedure to treat and prevent forefoot and midfoot ulcerations in patients with diabetes. Patients with diabetes are prone to plantar ulcerations due to a combination of factors, such as peripheral neuropathy, decreased tendon elasticity, peripheral vascular disease, and hyperglycemia. Complications such as re-ulceration and transfer lesion to the heel, associated with a calcaneal gait secondary to over-lengthening, are possible with percutaneous Achilles tendon lengthening. Although percutaneous Achilles tendon lengthening is well accepted, the overall incidence of complication has not been well described. A systematic review of the reported data was performed to determine the incidence of complication for percutaneous tendo-Achilles lengthening when used for the treatment and prevention of diabetic plantar ulcerations. Nine studies involving 490 percutaneous lengthening procedures met the inclusion criteria. The overall complication rate was 27.8% (8% with transfer heel ulcerations). Given the high rate of complications associated with a percutaneous Achilles tendon lengthening, careful patient selection and consideration of these risks should be considered prior to proceeding with this procedure. Additional prospective comparative analyses with standardization of surgical technique, degrees of lengthening achieved, and post-operative weightbearing and immobilization modalities are needed to decrease incidence of complication and achieve higher healing rates.

Prolonged Duration of Peripheral Nerve Blockade in a Pediatric Patient with Charcot Marie Tooth Disease: A Case Report

Charcot Marie Tooth disease is a common cause of pediatric peripheral neuropathy, which can lead to distal muscle wasting and weakness necessitating orthopedic procedures. We present an eleven-year-old male with Charcot Marie Tooth disease who received peripheral nerve blocks for ankle surgery, with a total dose of 1.75 mg/kg of bupivacaine 0.25%. Upon follow-up, it was identified that the sensory blockade did not resolve until thirty-six hours, postoperatively. There were no noted long-term sequalae on surgical follow-up. If a patient with Charcot Marie Tooth receives a peripheral nerve block, the patient should receive close short- and long-term follow-up to monitor for block complication or disease exacerbation.

Anesthetic Considerations for Patients with Hereditary Neuropathy with Liability to Pressure Palsies: A Narrative Review

Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal dominant demyelinating neuropathy characterized by an increased susceptibility to peripheral nerve injury from trauma, compression, or shear forces. Patients with this condition are unique, necessitating distinct considerations for anesthesia and surgical teams. This review describes the etiology, prevalence, clinical presentation, and management of HNPP and presents contemporary evidence and recommendations for optimal care for HNPP patients in the perioperative period. While the incidence of HNPP is reported at 7-16:100,000, this figure may be an underestimation due to underdiagnosis, further complicating medicolegal issues. With the subtle nature of symptoms associated with HNPP, patients with this condition may remain unrecognized during the perioperative period, posing significant risks. Several aspects of caring for this population, including anesthetic choices, intraoperative positioning, and monitoring strategy, may deviate from standard practices. As such, a tailored approach to caring for this unique population, coupled with meticulous preoperative planning, is crucial and requires a multidisciplinary approach.

The Efficacy of Neuromodulation Interventions for Chemotherapy-Induced Peripheral Neuropathy: A Systematic Review and Meta-Analysis

Purpose

To determine the efficacy and safety of a neuromodulation intervention regimen in the treatment of chemotherapy-induced peripheral neuropathy (CIPN).

Patients and Methods

Systematic searches were conducted in seven English databases. Randomized controlled trials of all neuromodulation interventions (both invasive and non-invasive) for the treatment of CIPN were selected. Group comparisons of differences between interventions and controls were also made. We divided the outcomes into immediate-term effect (≤3 weeks), short-term effect (3 weeks to ≤3 months), and long-term effect (>3 months).

Results

Sixteen studies and 946 patients with CIPN were included. Among immediate-term effects, neuromodulation interventions were superior to usual care for improving pain (SMD=-0.77, 95% CI -1.07~ 0.47), FACT-Ntx (MD = 5.35, 95% CI 2.84~ 7.87), and QOL (SMD = 0.44, 95% CI 0.09~ 0.79) (moderate certainty); neuromodulation loaded with usual care was superior to usual care for improving pain (SMD=-0.47, 95% CI -0.71 ~ -0.23), and QOL (SMD = 0.40, 95% CI 0.12 ~ 0.69) (moderate certainty). There were no statistically significant differences between the neuromodulation interventions regimen vs usual care in short- and long-term outcomes and neuromodulation vs sham stimulation from any outcome measure. There were mild adverse events such as pain at the site of stimulation and bruising, and no serious adverse events were reported.

Conclusion

Neuromodulation interventions had significant immediate-term efficacy in CIPN but had not been shown to be superior to sham stimulation; short-term and long-term efficacy could not be determined because there were too few original RCTs. Moreover, there are no serious adverse effects of this therapy.

The value of loss of protective pain sensation in predicting a first ulceration of the foot in people with diabetes

AIM

To determine both the risk of first ever ulcer (FEU) and its time to onset in a population which had loss of protective sensation (LOPS) in the foot either with or without loss of protective pain (LOPP).

METHODS

People with diabetes and LOPS without history of FEU presenting in a specialist clinic were included. LOPP was diagnosed by reduced vibration perception and pain perception by using a pinprick simulator. Participants were followed by routine foot checks, phone interview or by letter until the occurrence of a FEU, death or the end of observation period. Survival functions in LOPP strata were compared by log rank test. The hazard ratio (HR) of an FEU in people with compared to people without LOPP was estimated using Cox regression. Time to first ulcer was estimated using the framework of an accelerated failure time (AFT) model.

RESULTS

One hundred and thirty participants were followed up for a median of 48.3 months. Pain perception was lost in 55.4%. Eighteen people with LOPP developed a FEU (25.0%) as opposed to six (10.3%) of those with no LOPP (p = 0.02). Age-sex-adjusted HR for FEU was 3.0 (p = 0.02) for people with compared to people without LOPP. Age-sex-adjusted time to FEU for people with LOPP was approximately half (p = 0.03) than people without LOPP.

CONCLUSIONS

It is suggested that estimation of LOPP is included in routine practice because of its high predictive value for a FEU.

An adult patient with Tatton-Brown-Rahman syndrome caused by a novel DNMT3A variant and axonal polyneuropathy

Tatton-Brown-Rahman syndrome (TBRS) is a rare autosomal dominant overgrowth syndrome first reported in 2014 and caused by pathogenic variants in the DNA methyltransferase 3A (DNMT3A) gene. All individuals reported to date share a phenotype of somatic overgrowth, dysmorphic features, and intellectual disability. Peripheral neuropathy was not described in these cases. We report an adult patient with TBRS caused by a novel pathogenic DNMT3A variant (NM_175629.2: c.2036G>A, p.(Arg688His)) harboring an axonal length-dependent sensory-motor polyneuropathy. Extensive laboratory and molecular genetic work-up failed to identify alternative causes for this patient's neuropathy. We propose that axonal neuropathy may be a novel, age-dependent phenotypic feature in adults with TBRS and suggest that this syndrome should be considered in the differential diagnosis of patients with overgrowth, cognitive and psychiatric difficulties, and peripheral neuropathy.

Accelerated neuropathy among chronic kidney disease patients undergoing hemodialysis: Analysis of an institutional cluster

BACKGROUND

Accelerated neuropathy is a rare syndrome of rapidly worsening peripheral neuropathy, typically described in end-stage kidney disease (ESKD) patients undergoing dialysis. In our center, we encountered a surge in the occurrence of accelerated neuropathy among ESKD patients undergoing hemodialysis, which prompted systematic research.

METHODS

In this case-control study, we present the clinical features, electrophysiologic findings, and outcome of a series of patients who developed accelerated neuropathy after commencing hemodialysis for ESKD. Those who initiated hemodialysis and did not develop accelerated neuropathy were included as controls. We used logistic regression to identify predictors of accelerated neuropathy.

RESULTS

Among 436 ESKD patients who initiated hemodialysis over 4 years, 17 were diagnosed with accelerated neuropathy. The median-time (interquartile range) from hemodialysis initiation to presentation with accelerated neuropathy was 3 weeks (2-6). It typically presented as acute onset of unsteadiness of gait necessitating assistance for ambulation. Electrophysiology revealed length-dependent symmetric sensorimotor axonal neuropathy. Diabetes mellitus (odds ratio [OR] 4.1, 95% CI 1.2-13.9, p = 0.02), pre-existing peripheral neuropathy (OR 9.25, 95% CI 2.79-30.6, p < 0.001), and serum alkaline phosphatase (OR 1.2 for every 10 U increase, 95% CI 1.00-1.52, p = 0.04) significantly predicted accelerated neuropathy. With continued dialysis and supportive care, neurologic status improved, total-neuropathy score (summary score of peripheral nerve dysfunction incorporating clinical and electrophysiological parameters) declined from 26.5 to 18.4 (p < 0.001) and most regained unassisted ambulation.

CONCLUSION

This study presents the largest series of patients with accelerated neuropathy and has identified predictors. However, in view of the unusually high incidence of accelerated neuropathy we speculate that other unidentified factor(s) could be underlying its pathogenesis.

Neurofilament light chain concentration does not correlate with disease status in Labrador Retrievers affected with idiopathic laryngeal paralysis

OBJECTIVE

The aim of this study was to investigate whether plasma neurofilament light chain (pNfL) concentration was altered in Labrador Retrievers with idiopathic laryngeal paralysis (ILP) compared to a control population. A secondary aim was to investigate relationships between age, height, weight, and body mass index in the populations studied.

ANIMALS

123 dogs: 62 purebred Labrador Retrievers with ILP (ILP Cases) and 61 age-matched healthy medium- to large-breed dogs (Controls).

METHODS

Dogs, recruited from August 1, 2016, to March 1, 2022, were categorized as case or control based on a combination of physical exam, neurologic exam, and history. Blood plasma was collected, and pNfL concentration was measured. pNfL concentrations were compared between ILP Cases and Controls. Covariables including age, height, and weight were collected. Relationships between pNfL and covariables were analyzed within and between groups. In dogs where 2 plasma samples were available from differing time points, pNfL concentrations were measured to evaluate alterations over time.

RESULTS

No significant difference in pNfL concentration was found between ILP Cases and Control (P = .36). pNfL concentrations had moderate negative correlations with weight and height in the Control group; other variables did not correlate with pNfL concentrations in ILP Case or Control groups. pNfL concentrations do not correlate with ILP disease status or duration in Labrador Retrievers.

CLINICAL RELEVANCE

There is no evidence that pNfL levels are altered due to ILP disease duration or progression when compared with healthy controls. When evaluating pNfL concentrations in the dog, weight and height should be considered.

Phytic Acid Maintains Peripheral Neuron Integrity and Enhances Survivability against Platinum-Induced Degeneration via Reducing Reactive Oxygen Species and Enhancing Mitochondrial Membrane Potential

Phytic acid (PA) has been reported to possess anti-inflammatory and antioxidant properties that are critical for neuroprotection in neuronal disorders. This raises the question of whether PA can effectively protect sensory neurons against chemotherapy-induced peripheral neuropathy (CIPN). Peripheral neuropathy is a dose-limiting side effect of chemotherapy treatment often characterized by severe and abnormal pain in hands and feet resulting from peripheral nerve degeneration. Currently, there are no effective treatments available that can prevent or cure peripheral neuropathies other than symptomatic management. Herein, we aim to demonstrate the neuroprotective effects of PA against the neurodegeneration induced by the chemotherapeutics cisplatin (CDDP) and oxaliplatin. Further aims of this study are to provide the proposed mechanism of PA-mediated neuroprotection. The neuronal protection and survivability against CDDP were characterized by axon length measurements and cell body counting of the dorsal root ganglia (DRG) neurons. A cellular phenotype study was conducted microscopically. Intracellular reactive oxygen species (ROS) was estimated by fluorogenic probe dichlorofluorescein. Likewise, mitochondrial membrane potential (MMP) was assessed by fluorescent MitoTracker Orange CMTMRos. Similarly, the mitochondria-localized superoxide anion radical in response to CDDP with and without PA was evaluated. The culture of primary DRG neurons with CDDP reduced axon length and overall neuronal survival. However, cotreatment with PA demonstrated that axons were completely protected and showed increased stability up to the 45-day test duration, which is comparable to samples treated with PA alone and control. Notably, PA treatment scavenged the mitochondria-specific superoxide radicals and overall intracellular ROS that were largely induced by CDDP and simultaneously restored MMP. These results are credited to the underlying neuroprotection of PA in a platinum-treated condition. The results also exhibited that PA had a synergistic anticancer effect with CDDP in ovarian cancer in vitro models. For the first time, PA's potency against CDDP-induced PN is demonstrated systematically. The overall findings of this study suggest the application of PA in CIPN prevention and therapeutic purposes.

Boosting BDNF in muscle rescues impaired axonal transport in a mouse model of DI-CMTC peripheral neuropathy

Charcot-Marie-Tooth disease (CMT) is a genetic peripheral neuropathy caused by mutations in many functionally diverse genes. The aminoacyl-tRNA synthetase (ARS) enzymes, which transfer amino acids to partner tRNAs for protein synthesis, represent the largest protein family genetically linked to CMT aetiology, suggesting pathomechanistic commonalities. Dominant intermediate CMT type C (DI-CMTC) is caused by YARS1 mutations driving a toxic gain-of-function in the encoded tyrosyl-tRNA synthetase (TyrRS), which is mediated by exposure of consensus neomorphic surfaces through conformational changes of the mutant protein. In this study, we first showed that human DI-CMTC-causing TyrRSE196K mis-interacts with the extracellular domain of the BDNF receptor TrkB, an aberrant association we have previously characterised for several mutant glycyl-tRNA synthetases linked to CMT type 2D (CMT2D). We then performed temporal neuromuscular assessments of YarsE196K mice modelling DI-CMT. We determined that YarsE196K homozygotes display a selective, age-dependent impairment in in vivo axonal transport of neurotrophin-containing signalling endosomes, phenocopying CMT2D mice. This impairment is replicated by injection of recombinant TyrRSE196K, but not TyrRSWT, into muscles of wild-type mice. Augmenting BDNF in DI-CMTC muscles, through injection of recombinant protein or muscle-specific gene therapy, resulted in complete axonal transport correction. Therefore, this work identifies a non-cell autonomous pathomechanism common to ARS-related neuropathies, and highlights the potential of boosting BDNF levels in muscles as a therapeutic strategy.

TEAD1 is crucial for developmental myelination, Remak bundles, and functional regeneration of peripheral nerves

Previously we showed that the hippo pathway transcriptional effectors, YAP and TAZ, are essential for Schwann cells (SCs) to develop, maintain and regenerate myelin . Although TEAD1 has been implicated as a partner transcription factor, the mechanisms by which it mediates YAP/TAZ regulation of SC myelination are unclear. Here, using conditional and inducible knockout mice, we show that TEAD1 is crucial for SCs to develop and regenerate myelin. It promotes myelination by both positively and negatively regulating SC proliferation, enabling Krox20/Egr2 to upregulate myelin proteins, and upregulating the cholesterol biosynthetic enzymes FDPS and IDI1. We also show stage-dependent redundancy of TEAD1 and that non-myelinating SCs have a unique requirement for TEAD1 to enwrap nociceptive axons in Remak bundles. Our findings establish TEAD1 as a major partner of YAP/TAZ in developmental myelination and functional nerve regeneration and as a novel transcription factor regulating Remak bundle integrity.

Risk factors of paclitaxel-induced peripheral neuropathy in patients with breast cancer: a prospective cohort study

Objective

Chemotherapy-induced peripheral neuropathy (CIPN) is a common and severe adverse reaction in taxane-based chemotherapy. This study aimed to analyze the risk factors of peripheral neuropathy in patients with breast cancer receiving paclitaxel chemotherapy to provide a reference for the early prevention of CIPN.

Methods

We included 350 patients with breast cancer who received chemotherapy for the first time at the Tangshan People's Hospital between August 2022 and June 2023 and were followed for at least 3 months after the end of chemotherapy. The incidence of CIPN in patients with breast cancer was calculated, and risk factors for CIPN were analyzed using logistic regression analysis.

Results

The incidence rate of CIPN was 79.1%. Multifactor logistic regression analysis indicated that age ≥45 years [odds ratio (OR)=5.119, 95% confidence interval (CI)=1.395-18.780] and ≥60 years (OR=9.366, 95% CI=1.228-71.421), history of hypertension (OR=3.475, 95% CI=1.073-11.250), cumulative dose of chemotherapy drugs >900 mg (OR=4.842, 95% CI=1.961-5.946), vitamin D deficiency (OR=6.214, 95% CI=2.308-16.729), abnormal alanine aminotransferase (OR=3.154, 95% CI=1.010-9.844), anemia before chemotherapy (OR=2.770, 95% CI=1.093-7.019), infusion duration of chemotherapy drugs >30 min (OR=3.673, 95% CI=1.414-9.539), body mass index ≥24 kg/m2 (OR=8.139, 95% CI=1.157-57.240), mild depression (OR=4.546, 95% CI=1.358-15.223), and major depression (OR=4.455, 95% CI=1.237-16.037) increased the risk of CIPN. Having a regular caregiver (OR=0.223, 95% CI=0.087-0.573), high levels of physical activity (OR=0.071, 95% CI=0.008-0.647), and strong social support (OR=0.048, 95% CI=0.003-0.682) were protective factors against CIPN.

Conclusion

Clinical attention should be paid to patients with these risk factors, and active and effective preventive measures should be taken to reduce the occurrence of CIPN and improve the quality of life.

Electrodiagnostic studies and new diagnostic modalities for evaluation of peripheral nerve disorders

Electrodiagnostic studies (EDx) are frequently performed in the diagnostic evaluation of peripheral nerve disorders. There is increasing interest in the use of newer, alternative diagnostic modalities, in particular imaging, either to complement or replace established EDx protocols. However, the evidence to support this approach has not been expansively reviewed. In this paper, diagnostic performance data from studies of EDx and other diagnostic modalities in common peripheral nerve disorders have been analyzed and described, with a focus on radiculopathy, plexopathy, compressive neuropathies, and the important neuropathy subtypes of Guillain-Barré syndrome, chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), vasculitic neuropathy and diabetic neuropathy. Overall EDx retains its place as a primary diagnostic modality in the evaluated peripheral nerve disorders. Magnetic resonance imaging and ultrasound have developed important complementary diagnostic roles in compressive and traumatic neuropathies and atypical CIDP, but their value is more limited in other neuropathy subtypes. Identification of hourglass constriction in nerves of patients with neuralgic amyotrophy may have therapeutic implications. Investigation of radiculopathy is confounded by poor correlation between clinical features and imaging findings and the lack of a diagnostic gold standard. There is a need to enhance the literature on the utility of these newer diagnostic modalities.

Earlier diagnosis of peripheral neuropathy in primary care: A call to action

Peripheral neuropathy (PN) often remains undiagnosed (~80%). Earlier diagnosis of PN may reduce morbidity and enable earlier risk factor reduction to limit disease progression. Diabetic peripheral neuropathy (DPN) is the most common PN and the 10 g monofilament is endorsed as an inexpensive and easily performed test for DPN. However, it only detects patients with advanced neuropathy at high risk of foot ulceration. There are many validated questionnaires to diagnose PN, but they can be time-consuming and have complex scoring systems. Primary care physicians (PCPs) have busy clinics and lack access to a readily available screening method to diagnose PN. They would prefer a short, simple, and accurate tool to screen for PN. Involving the patient in the screening process would not only reduce the time a physician requires to make a diagnosis but would also empower the patient. Following an expert meeting of diabetologists and neurologists from the Middle East, South East Asia and Latin America, a consensus was formulated to help improve the diagnosis of PN in primary care using a simple tool for patients to screen themselves for PN followed by a consultation with the physician to confirm the diagnosis.

A Retrospective Study of Gemcitabine Plus Nab-Paclitaxel for Advanced Pancreatic Cancer Refractory to Gemcitabine Monotherapy

BACKGROUND/AIM

This study aimed to investigate the efficacy and safety of gemcitabine (GEM) plus nab-paclitaxel (nab-PTX), termed GnP, which is limited, in patients with advanced pancreatic cancer (PC) who show good tolerance to GEM monotherapy prior to being refractory to it.

PATIENTS AND METHODS

We retrospectively analyzed the data of patients with locally advanced or metastatic PC who received GEM followed by GnP between December 2014 and March 2019, regardless of the treatment line.

RESULTS

A total of 14 patients who received GnP after becoming refractory to GEM were included in this study. Eight patients were included in the nab-PTX-naïve group, seven of whom were treated with GEM monotherapy as first-line chemotherapy, and one was refractory to GEM monotherapy after modified FOLFIRINOX treatment. The other six patients were included in the nab-PTX reintroduction group. In this group, all patients received GnP followed by GEM maintenance therapy to prevent adverse events, such as peripheral neuropathy and fatigue. Two patients in the nab-PTX-naïve group showed partial response and none in the reintroduction group; median progression-free survival was 7.6 and 1.4 months and median overall survival was 9.4 and 6.2 months, respectively. In the safety analysis, grade 3 anemia and peripheral neuropathy were observed in one patient in the nab-PTX reintroduction group, while the remaining adverse events were of grade 1 or 2.

CONCLUSION

GnP is safe and effective even in patients with GEM-refractory PC, and GEM treatment followed by GnP can be an effective treatment option for patients with nab-PTX-naïve PC.

Clinical Features of Autoimmune Nodopathy With Anti-Neurofascin-155 Antibodies in South Koreans

BACKGROUND AND PURPOSE

Anti-neurofascin-155 (NF155) antibody is one of the autoantibodies associated with autoimmune nodopathy. We aimed to determine the clinical features of South Korean patients with anti-NF155-antibody-positive autoimmune nodopathy.

METHODS

The sera of 68 patients who fulfilled the diagnostic criteria for chronic inflammatory demyelinating polyneuropathy (CIDP) were tested for anti-NF155 antibodies using a cell-based assay (CBA) and enzyme-linked immunosorbent assay (ELISA). The anti-NF155-positive sera were also assayed for NF155 immunoglobulin G (IgG) subclasses, and for anti-NF186 and NF140 antibodies. The clinical features of the patients were reviewed retrospectively.

RESULTS

Among the 68 patients, 6 (8.8%) were positive for anti-NF155 antibodies in both the CBA and ELISA. One of those six patients was also positive for anti-NF186 and anti-NF140 antibodies. IgG4 was the predominant subclass in four patients. The mean age at onset was 32.2 years. All six positive patients presented with progressive sensory ataxia. Five patients treated using corticosteroids presented a partial or no response. All six patients were treated using intravenous immunoglobulin (IVIg). Among them, five exhibited a partial or poor response and the other exhibited a good response. All three patients treated using rituximab showed a good response.

CONCLUSIONS

The clinical characteristics of the patients were consistent with those in previous studies. Anti-NF155 antibody assay is necessary for diagnosing autoimmune nodopathy and its appropriate treatment, especially in young patients with CIDP who present with sensory ataxia and poor therapeutic responses to corticosteroids and IVIg.

Diagnostic biomarker for type 2 diabetic peripheral neuropathy via comprehensive bioinformatics analysis

BACKGROUND

Diabetic peripheral neuropathy (DPN) is a common complication of Type 2 diabetes mellitus (T2DM), which frequently results in disabling neuropathic pain and lower-limb amputation. The identification of noninvasive biomarkers for DPN may help early detection and individualized treatment of DPN.

METHODS

In this study, we identified differentially expressed genes (DEGs) between DPN and the control based on blood-source (GSE95849) and tissue-source gene expression profiles (GSE143979) from the Gene Expression Omnibus (GEO) database using limma, edgeR, and DESeq2 approaches. KEGGG and GO functional enrichments were performed. Hub genes and their correlation with infiltrating immune cells were analyzed. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to quantify hub gene expression.

RESULTS

In total, 144 DEGs between DPN and the control were identified. Functional enrichment revealed that the DEGs were mainly enriched in immune-related pathways like the Fc epsilon receptor Ig signaling pathway. By protein-protein interaction (PPI) network analysis, FCER1G, SYK, ITGA4, F13A1, MS4A2, and PTK2B were screened as hub genes with higher expression in DPN patients, among which half were immune genes (FCER1G, PTK2B, and SYK). RT-qPCR demonstrated that mRNA expression of FCER1G, PTK2B, and SYK was significantly increased in patients with DPN compared with both diabetic nonperipheral neuropathy (DNN) and normal subjects. The area under the receiver operating characteristic (ROC) curve of FCER1G, PTK2B, and SYK was 0.84, 0.81, and 0.73, respectively, suggesting their great advantages as diagnostic biomarkers to predict the progression of neuropathy in T2DM. Further analysis indicated that the expression of FCER1G, PTK2B, and SYK was negatively correlated with the cell proportion of significantly altered resting natural killer cells, T follicular helper cells, and activated mast cells, but positively correlated with monocytes.

CONCLUSIONS

Our findings demonstrated FCER1G, PTK2B, and SYK are potential diagnostic biomarkers and therapeutic targets for DPN, which provides new insight into DPN pathogenesis and therapies.

Unveiling peripheral neuropathy and cognitive dysfunction in diabetes: an observational and proof-of-concept study with video games and sensor-equipped insoles

Background

Proactive screening for cognitive dysfunction (CD) and peripheral neuropathy (PNP) in elderly patients with diabetes mellitus is essential for early intervention, yet clinical examination is time-consuming and prone to bias.

Objective

We aimed to investigate PNP and CD in a diabetes cohort and explore the possibility of identifying key features linked with the respective conditions by machine learning algorithms applied to data sets obtained in playful games controlled by sensor-equipped insoles.

Methods

In a cohort of patients diagnosed with diabetes (n=261) aged over 50 years PNP and CD were diagnosed based on complete physical examination (neuropathy symptom and disability scores, and Montreal Cognitive Assessment). In an observational and proof-of-concept study patients performed a 15 min lasting gaming session encompassing tutorials and four video games with 5,244 predefined features. The steering of video games was solely achieved by modulating plantar pressure values, which were measured by sensor-equipped insoles in real-time. Data sets were used to identify key features indicating game performance with correlation regarding CD and PNP findings. Thereby, machine learning models (e.g. gradient boosting and lasso and elastic-net regularized generalized linear models) were set up to distinguish patients in the different groups.

Results

PNP was diagnosed in 59% (n=153), CD in 34% (n=89) of participants, and 23% (n=61) suffered from both conditions. Multivariable regression analyses suggested that PNP was positively associated with CD in patients with diabetes (adjusted odds ratio = 1.95; 95% confidence interval: 1.03-3.76; P=0.04). Predictive game features were identified that significantly correlated with CD (n=59), PNP (n=40), or both (n=59). These features allowed to set up classification models that were enriched by individual risk profiles (i.e. gender, age, weight, BMI, diabetes type, and diabetes duration). The obtained models yielded good predictive performance with the area under the receiver-operating-characteristic curves reaching 0.95 for CD without PNP, 0.83 for PNP without CD, and 0.84 for CD and PNP combined.

Conclusions

The video game-based assessment was able to categorize patients with CD and/or PNP with high accuracy. Future studies with larger cohorts are needed to validate these results and potentially enhance the discriminative power of video games.

Spinal microglial M1 polarization contributes paclitaxel-induced neuropathic pain by triggering cells necroptosis

Paclitaxel (PTX) is a chemotherapeutic agent that is widely used for the treatment of several types of tumors. However, PTX-induced peripheral neuropathy (PIPN) is an adverse effect generally induced by long-term PTX use that significantly impairs the quality of life. Necroptosis has been implicated in various neurodegenerative disorders. Necroptosis of dorsal root ganglion neurons triggers the pathogenesis of PIPN. Therefore, the present study aims to investigate the role of spinal neuronal necroptosis in PIPN. It also explores the potential role of microglial polarization in necroptosis. We established rat models of PIPN via quartic PTX administration on alternate days (accumulated dose: 8 mg/kg). PTX induced obvious neuronal necroptosis and upregulated the expression of receptor-interacting protein kinase (RIP3) and mixed lineage kinase domain-like protein (MLKL) in the spinal dorsal horn. These effects were inhibited with a necroptosis pathway inhibitor, necrostatin-1 (Nec-1). The effect of microglial polarization on the regulation of spinal necroptosis was elucidated by administering minocycline to inhibit PTX-induced M1 polarization of spinal microglia caused by PTX. We observed a significant inhibitory effect of minocycline on PTX-induced necroptosis in spinal cord cells, based on the downregulation of RIP3 and MLKL expression, and suppression of tumor necrosis factor-α and IL-β synthesis. Additionally, minocycline improved hyperalgesia symptoms in PIPN rats. Overall, this study suggests that PTX-induced polarization of spinal microglia leads to RIP3/MLKL-regulated necroptosis, resulting in PIPN. These findings suggest a potential target for the prevention and treatment of neuropathic pain.

Pathologic classification of a late-onset peripheral neuropathy in a spontaneous Labrador retriever dog model

Late-onset peripheral neuropathy (LPN) is a heritable canine neuropathy commonly found in Labrador retrievers and is characterized by laryngeal paralysis and pelvic limb paresis. Our objective was to establish canine LPN as a model for human hereditary peripheral neuropathy by classifying it as either an axonopathy or myelinopathy and evaluating length-dependent degeneration. We conducted a motor nerve conduction study of the sciatic and ulnar nerves, electromyography (EMG) of appendicular and epaxial musculature, and histologic analysis of sciatic and recurrent laryngeal nerves in LPN-affected and control dogs. LPN-affected dogs exhibited significant decreases in compound muscle action potential (CMAP) amplitude, CMAP area, and pelvic limb latencies. However, no differences were found in motor nerve conduction velocity, residual latencies, or CMAP duration. Distal limb musculature showed greater EMG changes in LPN-affected dogs. Histologically, LPN-affected dogs exhibited a reduction in the number of large-diameter axons, especially in distal nerve regions. In conclusion, LPN in Labrador retrievers is a common, spontaneous, length-dependent peripheral axonopathy that is a novel animal model of age-related peripheral neuropathy that could be used for fundamental research and clinical trials.

Dihydromyricetin reverses capecitabine-induced peripheral myelin dysfunction through modulation of oxidative stress

Previous clinical reports have shown that capecitabine, an oral prodrug of 5-fluorouracil (5-Fu), can induce peripheral neuropathy, resulting in numbness, paresthesia and hypoesthesia. However, the mechanism through which capecitabine causes peripheral nerve injury remains unclear. Here, we demonstrate that systemic administration of capecitabine leads to myelin abnormalities in the peripheral nerves of mice, which are possibly attributed to the death of Schwann cells, the myelinating cells in the peripheral nervous system. Furthermore, our results show that 5-Fu induces significant oxidative stress in Schwann cells by inhibiting the expression of the anti-oxidative protein DJ-1, leading to a decrease in Schwann cell markers. We found that the anti-oxidant dihydromyricetin (DMY) reverses 5-Fu-induced Schwann cell death and oxidative stress and alleviates capecitabine-induced myelin abnormalities. Taken together, our data indicate that capecitabine induces peripheral myelin dysfunction by regulating DJ-1-mediated oxidative stress in Schwann cells and reveal DMY as a potential therapeutic strategy for capecitabine-induced peripheral neuropathy.

Comparison of characteristics of muscle magnetic resonance imaging findings in patients with antineutrophilic cytoplasmic antibody-associated vasculitis and polyarteritis nodosa

AIM

This study aimed to analyze the muscle magnetic resonance imaging (MRI) findings of patients with antineutrophilic cytoplasmic antibody-associated vasculitis (AAV) and polyarteritis nodosa (PAN) presenting with clinical symptoms in the extremities.

METHODS

Retrospective analysis was conducted on short tau inversion recovery MRI findings, with a focus on intramuscular vessels displaying abnormal perivascular signals, in 22 and eight patients with AAV and PAN, respectively. The number per unit area (4 cm2) and diameter of abnormal vessels on muscle MRI were compared between patients with AAV and those with PAN. Cut-off values, clinical sensitivity, and specificity for these indices were calculated from the receiver operating characteristic curves to distinguish between AAV and PAN, and the relationship between the indices and clinical findings in AAV was analyzed.

RESULTS

The number of abnormal vessels per unit area was significantly higher in AAV compared to PAN (p < .05). Additionally, the diameter of the abnormal vessels was significantly higher in PAN than in AAV (p < .05). The presence of >6.44 abnormal vessels per unit area or ≤3.61 mm diameter of abnormal vessels was able to predict AAV (sensitivity, 0.955; specificity, 0.625). AAV patients with peripheral neuropathy exhibited a significantly higher number of abnormal vessels per unit area than those without peripheral neuropathy (p < .05).

CONCLUSIONS

Muscle MRI can detect small- to medium-vessel vasculitis and be a valuable tool for distinguishing between patients with AAV and PAN experiencing clinical symptoms in the extremities.

Development of Cyclic Pressure Offloading Insole for Diabetic Foot Ulcer Prevention

Introduction. The likelihood of developing a diabetic foot ulcer (DFU) during one's lifetime for individuals with diabetes mellitus is around 19% to 34%. Continuous and repetitive loading on soft tissues are the major causative factors for DFU. This paper introduces an air cell array insole designed for cyclically offloading pressure from plantar regions to reduce repetitive stress and loading on foot. Materials and Methods. The insole comprises an air cell array insole and a pneumatic control unit. The interface pressure was evaluated in static and dynamic conditions at 3 different air cell internal pressures (6.9, 10.3, and 13.8 kPa). Plantar interface pressure was measured using a commercial pressure system, and data were analyzed using paired t test. Average interface pressure and peak pressure (PP) were studied to evaluate the functionality and effectiveness of the insole. Results. The analysis of static pressure data revealed that cyclic offloading significantly (p < .05) reduced PP in 4 tested cells corresponding to big toe, metatarsal heads, and heel areas with the maximum mean difference of 12.9 kPa observed in big toe region. Similarly, dynamic pressure data analysis showed that cyclic offloading significantly (p < .05) reduced PP in these areas, with the highest mean PP reduction of 36.98 kPa in the big toe region. Discussion. Results show the insole's capability to reduce plantar pressure through cyclic offloading. Internal pressure of air cells significantly affects the overall pressure reduction and must be chosen based on the user's weight. Conclusion. Results confirm that the insole with offloading capabilities has the potential to reduce the risk of developing DFUs by alleviating the plantar stress during both static and dynamic conditions.

The impact of scrambler therapy on pain and quality of life for chemotherapy-induced peripheral neuropathy: A pilot study

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating disturbance among patients who received chemotherapy, with no effective treatment available. Scrambler therapy (ST) is a noninvasive treatment capable of improving multiple quality-of-life symptoms beyond pain. We aimed to evaluate the efficacy of ST for pain and nonpain symptoms related to CIPN.

METHODS

Ten patients with moderate to severe CIPN symptoms for >3 months were enrolled in a single-arm trial of ST for 10 daily sessions. CIPN-related symptoms were measured throughout the treatment period and up to 6 months thereafter.

RESULTS

The worst pain was reduced by 6 months (p = 0.0039). QST demonstrated the greatest improvement in pressure of 60 g (p = 0.308, Cohen's d = 0.42) and cold temperature threshold of 2.5°C (p = 0.9375, Cohen's d = 0.51) in the gastrocnemius area. Symptoms of numbness, tingling, trouble walking, and disturbed sleep had significant improvements at 6 months. Pain medication use decreased by 70% at the end of treatment and by 42% at 6 months. Patient satisfaction was high (82%) and no adverse events with ST treatment were reported.

CONCLUSIONS

The results of this pilot trial support the use of ST by demonstrating improvement in multiple domains of quality of life for CIPN patients during an extended follow-up of 6 months. However, further large-scale studies are needed to confirm our findings.

Quantitative double echo steady state T2 mapping of upper extremity peripheral nerves and muscles

Introduction

T2 mapping can characterize peripheral neuropathy and muscle denervation due to axonal damage. Three-dimensional double echo steady-state (DESS) can simultaneously provide 3D qualitative information and T2 maps with equivalent spatial resolution. However, insufficient signal-to-noise ratio may bias DESS-T2 values. Deep learning reconstruction (DLR) techniques can reduce noise, and hence may improve quantitation of high-resolution DESS-T2. This study aims to (i) evaluate the effect of DLR methods on DESS-T2 values, and (ii) to evaluate the feasibility of using DESS-T2 maps to differentiate abnormal from normal nerves and muscles in the upper extremities, with abnormality as determined by electromyography.

Methods and results

Analysis of images from 25 subjects found that DLR decreased DESS-T2 values in abnormal muscles (DLR = 37.71 ± 9.11 msec, standard reconstruction = 38.56 ± 9.44 msec, p = 0.005) and normal muscles (DLR: 27.18 ± 6.34 msec, standard reconstruction: 27.58 ± 6.34 msec, p < 0.001) consistent with a noise reduction bias. Mean DESS-T2, both with and without DLR, was higher in abnormal nerves (abnormal = 75.99 ± 38.21 msec, normal = 35.10 ± 9.78 msec, p < 0.001) and muscles (abnormal = 37.71 ± 9.11 msec, normal = 27.18 ± 6.34 msec, p < 0.001). A higher DESS-T2 in muscle was associated with electromyography motor unit recruitment (p < 0.001).

Discussion

These results suggest that quantitative DESS-T2 is improved by DLR and can differentiate the nerves and muscles involved in peripheral neuropathies from those uninvolved.

Anti-neurofascin 155 Antibody-positive Neuropathy in a Human Immunodeficiency Virus-infected Patient

Human immunodeficiency virus (HIV)-associated neuropathy is a common complication of HIV infection and has several clinical subtypes. HIV-associated chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a demyelinating neuropathy whose clinical features are known to differ from those of CIDP in the HIV-uninfected population. We herein report a case of CIDP in an HIV-infected patient who was finally diagnosed with anti-neurofascin 155 (NF155) antibody-positive neuropathy. The clinical features, including clinical findings and therapeutic responses, were typical of paranodal antibody-mediated neuropathy. To our knowledge, this is the first case of anti-NF155 antibody-associated neuropathy in an HIV-infected patient.

Association of Hematological Parameters and Diabetic Neuropathy: A Retrospective Study

Background

Diabetic neuropathy (DN) is a common complication of type 2 diabetes (T2DM) and is characterized by persistent inflammation. Hematological parameters have emerged as a novel marker for detecting chronic inflammatory conditions, including diabetes.

Aim

We aim to examine the association between HbA1c levels, which can indicate the presence of diabetic neuropathy, and hematological parameters to explore the possibility of using hematological parameters as a new indicator for DN in T2DM patients.

Methods

This was a retrospective study of 768 (483 males and 284 females) medical records of adult T2DM patients with or without neuropathy who attending the outpatient neuromuscular clinic at King Abdul-Aziz University Hospital from January 2016 to December 2021.

Results

The results showed significant increases in HbA1c levels (p=0.000), lymphocyte levels (p=0.028), and the neutrophil-lymphocyte ratio (NLR) (p=0.011). In the T2DM group, HBA1C levels were found to be positively correlated with age (r=0.306, p=0.000), neutrophil (NEUT) (r=0. 287, p=0.000), platelet (PLT) (r=0. 148, p=0.039), and neutrophil-lymphocyte ratio (NLR) (r=0.306193, p=0.0007), and negatively correlated with gender (r=-0.306193, p=0.0007). In the T2DMN group, HBA1C levels showed a positive correlation with hemoglobin (HB) (r=0.084, p=0.045), PLT (r=0.087, p=0.037), and PLT/mean corpuscular hemoglobin (MCH) ratio (PLT/MCH ratio) (r=0.12, p=0.004), and a negative correlation with age (r=-0.204, p=0.000), gender (r=-0.086, p=0.041), weight (WT) (r=-0.113, p=0.007), Body Surface Area (BSA) (r=-0.09, p=0.031), mean corpuscular volume (MCV) (r=-0.292, p=0.000), and MCH (r=-0.186, p=0.000).

Conclusion

Our study found a significant association between HbA1c, a biomarker for diabetic neuropathy, and various hematological parameters (HB, MCV, MCH, PLT, PLT/MCH ratio) in T2DMN patients. By effectively controlling and monitoring these variables, it may be feasible to prevent or delay the progression of peripheral neuropathy in diabetic patients. However, further research is needed to validate these findings.

Multiparametric Quantitative MRI of Peripheral Nerves in the Leg: A Reliability Study

BACKGROUND

Patients with polyneuropathies typically have demyelination and/or axonal degeneration in peripheral nerves. Currently, there is a lack of imaging biomarkers to track the changes in these pathologies.

PURPOSE

To develop and evaluate the reliability of a multiparametric quantitative magnetic resonance imaging (qMRI) method of peripheral nerves in the leg.

STUDY TYPE

Prospective.

SUBJECTS

Seventeen healthy volunteers (36.2 ± 13.8 years old, 9 males) with 10 of them scanned twice for test-retest.

FIELD STRENGTH/SEQUENCE

3 T, three-dimensional gradient echo and diffusion tensor imaging.

ASSESSMENT

A qMRI protocol and processing pipeline was established for quantifying the following nerve parameters that are sensitive to myelin and axonal pathologies: magnetization transfer (MT) ratio (MTR), MT saturation index (MTsat), T2 *, T1 , proton density (PD), fractional anisotropy (FA), and mean/axial/radial diffusivities (MD, AD, and RD). The qMRI protocol also measures the volume of nerve fascicles (fVOL) and the fat fraction (FF) of muscles.

STATISTICAL TESTS

The intersession reproducibility and inter-rater reliability of each qMRI parameter were assessed by Bland-Altman analysis and intraclass correlation coefficient (ICC). Pairwise Pearson correlation analyses were performed to investigate the intrinsic association between qMRI parameters. Distal-to-proximal variations were evaluated by paired t-tests with Bonferroni-Holm multiple comparison corrections. P < 0.05 was considered statistically significant.

RESULTS

The MTR, MTsat, T2 *, T1 , PD, FA, AD, and fVOL of the sciatic and tibial nerves, and the FF of leg muscles, had an overall good-to-excellent test-retest agreement (ICC varying from 0.78 to 0.99). All the qMRI parameters had good-to-excellent inter-rater reliability (ICC > 0.80). The data demonstrated a pattern of distal-to-proximal changes of an increased nerve MTsat and FA, and a decreased nerve T1 , PD, MD, and RD, as well as a significantly increased muscle FF.

DATA CONCLUSION

The proposed multiparametric qMRI method of the peripheral nerves is highly reproducible and provided healthy control data which will be used in developing monitoring biomarkers in patients with polyneuropathies.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY: Stage 2.

Plasmablastic Myeloma: An Unusual Cause of Peripheral Facial Paralysis

Peripheral facial paralysis refers to the involvement of the facial nerve (VII cranial nerve) at any point along its path, which starts from its nucleus, located in the pons, and extends to its most distal branches. The etiology is heterogeneous, including viral infections, bacterial infections, trauma, and neoplasms, among others. However, in the majority of cases, the cause is idiopathic, commonly referred to as Bell's palsy. The diagnosis is therefore one of exclusion, based in particular on the physical examination. Naturally, the diagnosis is decisive in directing the therapeutic approach. However, the signs/symptoms of the various primary pathological processes can appear late in the course of the disease. This is why the Physical Medicine and Rehabilitation specialist is particularly important, since, in addition to the initial assessment, he or she monitors the patient more closely and over a longer period of time, together with the team of therapists. New clinical findings and diagnostic tests requested accordingly can dramatically change the initial diagnosis and guide new treatments. We present the clinical case of a 60-year-old man initially diagnosed with Bell's palsy, whose poor clinical evolution and new clinical findings during the rehabilitation program led to the diagnosis of plasmablastic myeloma and a radically different therapeutic approach.

Pharmacokinetic-toxicodynamic Modeling to Elucidate the Involvement of Dorsal Root Ganglion Neuron in Oxaliplatin-induced Peripheral Neuropathy

BACKGROUND/AIM

Oxaliplatin (L-OHP)-induced peripheral neuropathy (OIPN) limits L-OHP dosage due to nerve cell damage in the dorsal root ganglion (DRG) caused by platinum (Pt). Despite various recommended approaches for OIPN management, no effective approach has been established. The aim of this study was to evaluate Pt distribution into DRG after repeat administrations of L-OHP in rats and to develop a pharmacokinetic-toxicodynamic (PK-TD) model using Pt concentrations in DRG to predict neuropathy severity.

MATERIALS AND METHODS

Male Wistar rats were administered L-OHP (3, 5, or 8 mg/kg i.v.) once weekly. Blood and DRG samples were collected following L-OHP administration. For toxicodynamic (TD) study, OIPN was evaluated using the von Frey test. Plasma and DRG Pt concentrations and thresholds values in von Frey test were used for PK-TD modeling using Phoenix WinNonlin® version 8.3 software.

RESULTS

Pt concentration in the DRG increased with repeated administration of L-OHP in a dose-dependent manner, indicating Pt accumulation in DRG following multiple administrations. The PK-TD model, consisting of an indirect response model and a transit compartment model with the DRG compartment, adequately described the temporal changes in OIPN with reliable TD parameters (≤36.4% with coefficient of variation). The maximum drug inhibition model could be employed to establish a quantitative correlation between the Pt content present in the DRG and the toxic potency resulting in OIPN.

CONCLUSION

The utility of the PK-TD model for predicting neuropathy outcomes was established, suggesting that models composed of the DRG compartment contribute to determining an optimal dosing strategy for reducing OIPN.

Hand conditions as sequelae of infection with COVID-19: a literature review

Patients have attended our clinics with various hand pathologies after contracting COVID-19 or receiving vaccination. We postulate the virus stimulates a systemic inflammatory response that triggers these pathologies and conducted a search of the literature for associated conditions. Twenty publications were included for this review. Three studies identified skeletal muscle inflammation, and several identified reactive arthritis post-infection. Rheumatoid arthritis post-infection was also recognized, along with crystalline arthropathy. Carpal tunnel syndrome was seen in two cases. There is a current paucity in published scientific material regarding COVID-19 sequalae in the hand. This review aims to stimulate discussion in how a virus can induce pathological processes causing common hand pathologies.

Initial validation of the Mass. General Neuropathy Exam Tool (MAGNET) for evaluation of distal small-fiber neuropathy

INTRODUCTION/AIMS

Diagnosis of small-fiber neuropathy (SFN) is hampered by its subjective symptoms and signs. Confirmatory testing is insufficiently available and expensive, so predictive examinations have value. However, few support the 2020 SFN consensus-case-definition requirements or were validated for non-diabetes neuropathies. Thus we developed the Massachusetts General Hospital Neuropathy Exam Tool (MAGNET) and measured diagnostic performance in 160 symptomatic patients evaluated for length-dependent SFN from any cause and 37 healthy volunteers.

METHODS

We compared prevalences of abnormalities (vital signs, pupil responses, lower-limb appearance, pin, light touch, vibration and position sensitivity, great-toe strength, muscle stretch reflexes), and validated diagnostic performance against objective SFN tests: lower-leg skin-biopsy epidermal neurite densities and autonomic function testing (AFT). Sensitivity/specificity, feasibility, test-retest and inter-rater reliability, and convergence with the Utah Early Neuropathy Scale were calculated.

RESULTS

Patients' ages averaged 48.5 ± 14.7 years and 70.6% were female. Causes of neuropathy varied, remaining unknown in 59.5%. Among the 46 with abnormal skin biopsies, the most prevalent abnormality was reduced pin sharpness at the toes (71.7%). Inter-rater reliability, test-retest reliability, and convergent validity excelled (range = 91.3-95.6%). Receiver operating characteristics comparing all symptomatic patients versus healthy controls indicated that a MAGNET threshold score of 14 maximized predictive accuracy for skin biopsies (0.74) and a 30 cut-off maximized accuracy for predicting AFT (0.60). Analyzing patients with any abnormal neuropathy-test results identified areas-under-the-curves of 0.87-0.89 for predicting a diagnostic result, accuracy = 0.80-0.89, and Youden's index = 0.62. Overall, MAGNET was 80%-85% accurate for stratifying patients with abnormal versus normal neuropathy test results.

DISCUSSION

MAGNET quickly generates research-quality metrics during clinical examinations.

A patient with bilateral neuralgic amyotrophy and hepatitis E virus infection: an educational communication

Neuralgic Amyotrophy, a peripheral nervous system disorder, is characterized by severe pain and muscle weakness, which can have a significant impact on patients' quality of life. The exact cause of neuralgic amyotrophy is unknown, but it may be linked to immunopathological mechanisms. Recent research has found an association between neuralgic amyotrophy and hepatitis E virus infection. This communication aims to expand knowledge on the clinical phenotype of patients with neuralgic amyotrophy and hepatitis E virus infection, presenting the case of a 55-year-old man diagnosed with bilateral neuralgic amyotrophy and hepatitis E virus infection.

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.

Targeting SARM1 improves autophagic stress-induced axonal neuropathy

ABBREVIATIONS

AAV: adeno-associated virus; ATF3: activating transcription factor 3; ATG7: autophagy related 7; AVIL: advillin; cADPR: cyclic ADP ribose; CALC: calcitonin/calcitonin-related polypeptide; CMT: Charcot-Marie-Tooth disease; cKO: conditional knockout; DEG: differentially expressed gene; DRG: dorsal root ganglion; FE-SEM: field emission scanning electron microscopy; IF: immunofluorescence; NCV: nerve conduction velocity; PVALB: parvalbumin; RAG: regeneration-associated gene; ROS: reactive oxygen species; SARM1: sterile alpha and HEAT/Armadillo motif containing 1; SYN1: synapsin I.

[Role and place of ipidacrine in the therapy of diseases of the peripheral nervous system. The resolution of the expert council]

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.

Effects of vincristine and monosodium glutamate on gastrointestinal motility and visceral sensitivity

BACKGROUND

Chemotherapy-induced adverse effects are an unresolved nightmare. In preclinical studies in rats, the food additive monosodium glutamate (MSG) improved some of the side effects caused by cisplatin, but its effects in other models of chemotherapy-treated animals are not well known. The aim of this study was to test if MSG may improve some of the adverse effects induced by vincristine in rats.

METHODS

Young male Wistar rats were exposed or not to MSG (4 g L-1 ) in drinking water from week 0 till 1 week after treatment (week 3). Rats received two cycles of five daily intraperitoneal (ip) injections (Monday to Friday, weeks 1 and 2) of either saline (2 mL kg-1 ) or vincristine (0.1 mg kg-1 ). Gastrointestinal motility was measured in vivo by radiological methods after the first and tenth ip administrations. On week 3, the threshold for mechanical somatic and colorectal sensitivity was recorded using Von Frey filaments applied to the paws and an intracolonic balloon, respectively. Finally, samples of the terminal ileum and distal colon were histologically evaluated in sections.

KEY RESULTS

Vincristine reduced body weight gain, food intake, and upper gastrointestinal transit, caused somatic (but not visceral) hypersensitivity and increased the thickness of the submucosal and muscle layers of the small intestine. In vincristine-treated animals, MSG partially prevented gastrointestinal dysmotility and reduced visceral sensitivity but did not improve structural alterations of the small intestine.

CONCLUSIONS & INFERENCES

MSG could be used as an adjuvant to conventional treatments to improve some gastrointestinal dysfunctions caused by chemotherapy.

Prospective analysis of patient-reported outcomes and physician-reported outcomes with gynecologic cancer chemotherapy

OBJECTIVE

Gynecologic cancer chemotherapy impacts the quality of life (QOL) of patients, with lasting adverse events that may require treatment adjustments or discontinuation. Consequently, real-time symptom monitoring before outpatient visits has resulted in improved QOL for patients and extended survival times. This study investigated whether there are differences between electronic patient-reported outcomes (e-PRO-CTCAE) and physician-assessed outcomes (NCI-CTCAE) evaluated in an outpatient setting in gynecologic cancer chemotherapy.

METHODS

The study was conducted on 50 patients who received their first chemotherapy treatment at St. Marianna University Hospital Obstetrics and Gynecology from July 1, 2021 to December 31, 2022. PRO-CTCAE and NCI-CTCAE were evaluated at each instance of chemotherapy and 2 weeks after. The PRO-CTCAE was additionally collected weekly using e-PRO.

RESULTS

The values for "Joint Pain," "Nausea," "Taste Disturbance," "Constipation," "Insomnia," "Fatigue," "Limb Edema," and "Concentration Impairment" were consistently higher in PRO-CTCAE than in NCI-CTCAE, indicating that physicians underestimated the severity of adverse events. In contrast, there was no significant difference in "Peripheral Neuropathy," demonstrating that physicians had a good understanding of this condition in patients. The weekly responses obtained from e-PRO revealed that symptom exacerbations peaked outside of clinic visits.

CONCLUSIONS

This study demonstrated physicians tend to underestimate most adverse events. Moreover, the responses using e-PRO revealed peak symptom deterioration occurred outside of outpatient visits. This suggested that e-PRO and actions taken in response to them can improve patients' QOL.

Iron role paradox in nerve degeneration and regeneration

Iron accumulates in the neural tissue during peripheral nerve degeneration. Some studies have already been suggested that iron facilitates Wallerian degeneration (WD) events such as Schwann cell de-differentiation. On the other hand, intracellular iron levels remain elevated during nerve regeneration and gradually decrease. Iron enhances Schwann cell differentiation and axonal outgrowth. Therefore, there seems to be a paradox in the role of iron during nerve degeneration and regeneration. We explain this contradiction by suggesting that the increase in intracellular iron concentration during peripheral nerve degeneration is likely to prepare neural cells for the initiation of regeneration. Changes in iron levels are the result of changes in the expression of iron homeostasis proteins. In this review, we will first discuss the changes in the iron/iron homeostasis protein levels during peripheral nerve degeneration and regeneration and then explain how iron is related to nerve regeneration. This data may help better understand the mechanisms of peripheral nerve repair and find a solution to prevent or slow the progression of peripheral neuropathies.

Diagnostic and therapeutic value of intracellular biomarker testing in chronic pain

Aim: Micronutrient and metabolic compound supplementation as a method of treating chronic pain is not well understood. Case: A 58 year-old woman presented with refractory painful neuropathy. She did not respond to conservative treatment and was seeking spinal cord stimulator implantation. She underwent a biomarker panel that revealed low intracellular levels of multiple compounds. As she supplemented her deficiencies, her symptoms fully resolved, and the implant was no longer indicated. Discussion: Micronutrient and metabolic compound testing could potentially expand non-invasive treatment options for patients with refractory chronic pain. Caution should be exercised given limited regulatory oversight in the supplement industry and actively ongoing nutritional research. Conclusion: Biomarker testing panels may be a useful adjunct in the management of refractory neuropathic pain.

The Long-term Lung and Respiratory Outcomes of Acid Sphingomyelinase Deficiency: A 10- and 20-year Follow-up Study

BACKGROUND/AIM

Acid sphingomyelinase deficiency (ASMD) is a rare lysosomal storage disorder characterized by sphingomyelin accumulation causing progressive lung disease, respiratory failure, and death.

PATIENTS AND METHODS

This retrospective observational study used the TriNetX database of electronic health records for 15,108 patients with ASMD from 2000-2020. After exclusions, 8,980 individuals were followed for 10 or 20 years. Outcomes included incidence and prevalence of respiratory disorders. Associations of age, sex and race were assessed.

RESULTS

Nearly all respiratory outcomes increased significantly over 20 versus 10 years. Other respiratory disorders, specified respiratory disorders and secondary pulmonary hypertension exhibited the greatest increases, reflecting progressive lung damage in ASMD. While outcomes were poor overall, older age, male sex, and racial minority status associated with greater risks, indicating differences in disease progression or care.

CONCLUSION

This study confirms the progressive nature of ASMD and need for close monitoring and treatment of pulmonary complications to reduce long-term morbidity and mortality. Genetic testing enabling diagnosis even for milder, adult-onset forms is critical to optimize outcomes.

Peripheral Nerve Stimulation With a High-Frequency Electromagnetic Coupled Powered Implanted Receiver at the Posterior Tibial Nerve for the Treatment of Chronic Pain in the Foot

INTRODUCTION

Peripheral neuropathy has several causes, with diabetes being the most common. Conservative management may fail to control pain. Our study aimed at evaluating the use of peripheral nerve stimulation of the posterior tibial nerve for treating peripheral neuropathy.

MATERIALS AND METHODS

This was an observational study of 15 patients who received peripheral nerve stimulation at the posterior tibial nerve to treat peripheral neuropathy. Outcomes measured were improvement of pain scores and Patient Global Impression of Change (PGIC) at 12 months compared with before the implant.

RESULTS

Mean pain scores with the verbal rating scale were 3 ± 1.8 at >12 months compared with 8.6 ± 1.2 at baseline, a reduction of 65% (p < 0.001). Median satisfaction with the PGIC at >12 months was 7 of 7, with most subjects reporting a 6 (better) or a 7 (a great deal better).

CONCLUSION

Peripheral nerve stimulation of the posterior tibial nerve can be a safe and effective modality for treating chronic pain symptoms related to peripheral neuropathy of the foot.

The Regentime stem cell procedure, successful treatment for a Charcot-Marie-Tooth disease case

This report highlights the successful treatment of a Charcot-Marie-Tooth disease case using the Regentime stem cell procedure, suggesting its potential as a promising therapeutic approach for patients suffering from this challenging condition.

Respiratory syncytial virus infects peripheral and spinal nerves and induces chemokine-mediated neuropathy

Respiratory syncytial virus (RSV) primarily infects the respiratory epithelium, but growing evidence suggests it may also be responsible for neurological sequelae. In 3D microphysiological peripheral nerve cultures, RSV infected neurons, macrophages, and dendritic cells along two distinct trajectories depending on the initial viral load. Low-level infection was transient, primarily involved macrophages, and induced moderate chemokine release with transient neural hypersensitivity. Infection with higher viral loads was persistent, infected neuronal cells in addition to monocytes, and induced robust chemokine release followed by progressive neurotoxicity. In spinal cord cultures, RSV infected microglia and dendritic cells but not neurons, producing a moderate chemokine expression pattern. The persistence of infection was variable but could be identified in dendritic cells as long as 30 days post-inoculation. This study suggests that RSV can disrupt neuronal function directly through infection of peripheral neurons and indirectly through infection of resident monocytes, and inflammatory chemokines likely mediate both mechanisms.

An aqueous Commiphora myrrha extract ameliorates paclitaxel-induced peripheral neuropathic pain in mice

Background: Chemotherapy-induced neuropathic pain (CINP) is a debilitating side effect in individuals undergoing cancer treatment. Treatment of CINP with the current available classes of drugs is limited and often yields unsatisfactory results. Finding therapeutic alternatives of plant origin could provide a new way for the management of CINP. Commiphora myrrha (CM) resin extract has been reported to have anti-inflammatory and analgesic activities, but the effect of CM on neuropathic pain is yet to be investigated in CINP. Objectives: The aim of this study was to investigate the antinociceptive effect of CM extract in a mouse model of paclitaxel-induced neuropathic pain (PINP). Methods: The effects of CM on thermal hyperalgesia and mechanical allodynia were assessed in female BALB/c mice with PINP using a hot plate and a plantar aesthesiometer, respectively. Motor coordination was evaluated using a rotarod apparatus. The involvement of transient receptor potential vanilloid channel 1 (TRPV1) in CM actions was investigated using a capsaicin (a TRPV1 agonist)-induced nociception test. The genetic expression of Trpv1, Nrf2, Sod2, and Hmox1 was assessed using real-time PCR, while protein expression of TRPV1, Iba-1, and CD11b was assessed using Wes™. Results: Administration of CM to mice with established PINP produced a dose-dependent reduction in thermal hyperalgesia. Prophylactic treatment of mice with CM prevented the development of paclitaxel-induced thermal hyperalgesia and mechanical allodynia. CM did not change the motor coordination of mice, as the reaction latency and the rotational velocity of animals pretreated with CM extract were similar to those of animals pretreated with vehicle. CM significantly decreased the number and duration of the flick responses following capsaicin injection into the dorsal surface of the hind paw of mice. The protein expression of TRPV1 was upregulated in the spinal cord of paclitaxel-treated animals compared to vehicle-only-treated control animals, while CM-treated animals had values similar to vehicle-only-treated control animals. The mRNA expression of Nrf2, a major antioxidant transcription factor, was upregulated in the paw skin of mice treated with CM compared to those treated with paclitaxel alone. Conclusion: These results indicate that CM may both treat established and prevent the development of paclitaxel-induced thermal hyperalgesia and mechanical allodynia without any impairment in the motor activity of mice. CM may mediate its action through the peripheral inhibition of TRPV1 channel activity, restoration of normal TRPV1 protein expression in the spinal cord, and elevation of cellular antioxidant defenses. CM has the potential to be used as a therapeutic alternative to treat CINP.

Peripheral Neuropathy in Virologically Suppressed People Living with HIV: Evidence from the PIVOT Trial

The aim of this study is to identify the factors associated with peripheral neuropathy and to explore neurofilament light chain (NfL) as a biomarker for peripheral neuropathy (PN) in effectively virologically suppressed adults living with HIV. All protease inhibitor monotherapy versus ongoing triple therapy in the long-term management of HIV infection (PIVOT) trial participants with data on PN at baseline were included in the study. NfL plasma levels (pNfL) were measured in a sub-set of participants. Multivariable logistic regression was used to examine the associations of PN with potential risk factors (including age, sex, nadir CD4 cell count, history of dideoxynucleoside (d-drugs) exposure, and blood glucose levels) and NfL levels. Of the 585 participants included, 131 (22.4%) reported PN during the study period (median of 44 months). The participants were predominantly male (76.6%), White (68.2%), and virologically suppressed for a median period of 37 months (range of 20-63) before recruitment. The age at baseline was 44.3 years (standard deviation (SD) of 9.2). PN was independently associated with age (adjusted odds ratio (aOR) = 1.35, 95% CI of 1.20-1.52; additional 5 years), history of d-drugs (aOR 1.88, 95% CI of 1.12-3.16), height (aOR 1.19, 95% CI of 1.05-1.35; additional 5 cm), nadir CD4 cell count (aOR 1.10 CI of 1.00-1.20; 50 cells fewer), and metabolic syndrome (aOR 2.31, 95% CI of 1.27 4.20), but not pNfL. The excess risk for PN associated with d-drug use remains after the exposure has stopped for years, suggesting non-reversible toxicity. In people with HIV, metabolic syndrome is independently associated with PN. There was no additional value for pNfL as a screening test for peripheral neuropathy in effectively virologically suppressed adults living with HIV.

Arm Length-Does It Influence Late Response in a Nerve Conduction Study?

Introduction  F wave response, a late response obtained from a motor nerve, can be influenced by various external factors like gender, temperature, height, weight, and limb length, and hence it causes variation in the measured parameters. Since very few studies have studied the impact of arm length on the F wave, this study was conducted to analyze the relation between the arm length on various parameters of F wave and hence to consider the importance of it during conduct of a nerve conduction study. Methods  The study was conducted among 40 healthy individuals and 40 diabetics with neuropathy. The arm length was measured in the upper limbs in both the groups and F wave was recorded following a conventional procedure using a standardized instrument. Results  This study showed that in the upper limbs of both the groups, there existed a positive correlation for certain parameters like minimum, maximum and mean latencies, persistence, FM latency and M latency, and a negative correlation for chronodispersion. Conclusion  F wave parameters should be adjusted for arm length to improve the sensitivity and diagnostic ability of neurological testing.

Feasibility of therapeutic Chinese massage (tui na) for peripheral neuropathy among people with human immunodeficiency virus: findings of a pilot randomized controlled trial

Background

Peripheral neuropathy (PN) is prevalent in people with human immunodeficiency virus (PHIV) with no Food and Drug Administration-approved treatment. Therapeutic Chinese massage (TCM) is a promising noninvasive and non-harmful intervention for HIV-related PN. However, relevant research is lacking. The purpose of this study is to evaluate the feasibility of TCM for HIV-related PN.

Method

We conducted a pilot, single-centered, two-arm, double-blinded, randomized controlled trial. Twenty eligible PHIV were recruited primarily from the AIDS Foundation Houston, Inc. in Texas and were randomly assigned into two groups. Ten participants in the intervention group received three weekly 25-min TCM sessions by a certified TCM therapist. The remaining ten control group participants received the same therapist's three weekly 25-min placebo massage sessions on their lower extremities. The outcome was the feasibility of this study as measured by recruitment and completion rates, participant safety, and treatment adherence and compliance, as well as the effect size of the intervention.

Results

The study population comprised 20 PHIV (mean age 55.23). This study showed high feasibility as measured by a high rate of recruitment, a 100% rate of completion, and zero serious adverse events. As we inquired 21 respondents for eligibility for the study, all except one had HIV-related PN. All respondents were willing to participate in the study and adhered to the group assignment after they enrolled in the study. The participants' baseline pain was at a medium to a high level (6.30 [2.15] out of 10).

Conclusion

Chinese massage is a feasible intervention in PHIV. Future relevant randomized controlled trials are expected.

Clinical trial registration

https://clinicaltrials.gov/, NCT05379140.

Validity and Reliability of a Vibration-Based Cell Phone in Detecting Peripheral Neuropathy among Patients with a Risk of Diabetic Foot Ulcer

The aim of this study was to determine the validity and reliability of a vibration-based cell phone in detecting peripheral neuropathy among individuals with a risk of diabetic foot ulcer (DFU). The current study consisted of 3 phases: a pilot study, concurrent validity study, and interreliability study. A 128 Hz tuning fork and vibration-based cell phone using the Vibrations-Test app was compared in the primary care setting. The pilot study confirmed that the vibration-based cell phone has an adequate reliability (r > 0.70, P < .001). The concurrent validity test involved 96 participants (aged 55.78 ± 8.32 years). The Pearson correlation test found the highest correlation in the fifth metatarsal heads (r = 0.741, right feet; 0.772, left feet; P < .001). In the 4 primary care settings, the interrater reliability between nurses of the vibration-based cell phone were k = 1.000, 1.000, 1.000, and 0.720. The concurrent validity test found moderate to strong correlation results and that the interrater reliability had a strong agreement that was almost perfect. Thus, vibration-based cell phone applications can be used as screening tools for detecting neuropathy among individuals with a risk of DFU.