Paraneoplastic neuropathies and peripheral nerve hyperexcitability disorders.

Peripheral neuropathy is a common referral for patients to the neurologic clinics. Paraneoplastic neuropathies account for a small but high morbidity and mortality subgroup. Symptoms include weakness, sensory loss, sweating irregularity, blood pressure instability, severe constipation, and neuropathic pain. Neuropathy is the first presenting symptom of malignancy among many patients. The molecular and cellular oncogenic immune targets reside within cell bodies, axons, cytoplasms, or surface membranes of neural tissues. A more favorable immune treatment outcome occurs in those where the targets reside on the cell surface. Patients with antibodies binding cell surface antigens commonly have neural hyperexcitability with pain, cramps, fasciculations, and hyperhidrotic attacks (CASPR2, LGI1, and others). The antigenic targets are also commonly expressed in the central nervous system, with presenting symptoms being myelopathy, encephalopathy, and seizures with neuropathy, often masked. Pain and autonomic components typically relate to small nerve fiber involvement (nociceptive, adrenergic, enteric, and sudomotor), sometimes without nerve fiber loss but rather hyperexcitability. The specific antibodies discovered help direct cancer investigations. Among the primary axonal paraneoplastic neuropathies, pathognomonic clinical features do not exist, and testing for multiple antibodies simultaneously provides the best sensitivity in testing (AGNA1-SOX1; amphiphysin; ANNA-1-HU; ANNA-3-DACH1; CASPR2; CRMP5; LGI1; PCA2-MAP1B, and others). Performing confirmatory antibody testing using adjunct methods improves specificity. Antibody-mediated demyelinating paraneoplastic neuropathies are limited to MAG-IgM (IgM-MGUS, Waldenström's, and myeloma), with the others associated with cytokine elevations (VEGF, IL6) caused by osteosclerotic myeloma, plasmacytoma (POEMS), and rarely angiofollicular lymphoma (Castleman's). Paraneoplastic disorders have clinical overlap with other idiopathic antibody disorders, including IgG4 demyelinating nodopathies (NF155 and Contactin-1). This review summarizes the paraneoplastic neuropathies, including those with peripheral nerve hyperexcitability.

Elevated liver enzymes and fasting glucose levels correlate with neuropathy in patients diagnosed with alcohol use disorder independently of the blood thiamine levels.

AIMS: Chronic alcohol consumption is well known to cause peripheral neuropathy, affecting both small and large nerve fibers. The aim of this study was to correlate biochemical and neurophysiological findings and investigate possible biomarkers and risk factors for pathogenetic mechanisms of neuropathy in patients diagnosed with alcohol use disorder (AUD). METHODS: Ninety patients diagnosed with AUD were enrolled in this prospective study over a period of 3 years. Serum biochemical parameters, as well as thiamine blood levels, were determined upon admission. Every subject was assessed by clinical neurological examination, followed by Nerve Conduction Studies, Quantitative Sensory Testing, and Sympathetic Skin Response. Fifty age and gender-matched patients without a diagnosis of AUD were used as the control group. RESULTS: Peripheral neuropathy was diagnosed in 54 patients (60%). Among them, pure large fiber neuropathy was found in 18 patients, pure small fiber neuropathy in 12 patients, and both large and small fiber neuropathy was diagnosed in 24 patients. Elevated liver enzymes and fasting glucose levels upon admission were significantly correlated with neuropathy. Lower blood thiamine levels (than reference) were found in seven patients and were not correlated with neuropathy. CONCLUSIONS: Our study suggests that alcohol-related liver dysfunction and hyperglycemia may contribute as risk factors of peripheral neuropathy in patients diagnosed with AUD, while blood thiamine levels do not correlate with neuropathy. Moreover, we suggest that liver enzymes and the De Ritis ratio could be potentially used as biomarkers for the incidence and severity of alcohol-related neuropathy.

Study protocol: fish oil supplement in prevention of oxaliplatin-induced peripheral neuropathy in adjuvant colorectal cancer patients - a randomized controlled trial. (OxaNeuro).

BACKGROUND: Oxaliplatin-induced peripheral neuropathy (OIPN) in general and painful OIPN in particular is a debilitating late effect that severely affects cancer survivors' quality of life and causes premature cessation of potentially lifesaving treatment. No preventive treatments and no effective treatment for chronic OIPN exist despite many attempts. One of several suggested mechanisms includes neuroinflammation as a contributing factor to OIPN. Fish oil containing long-chain n-3 polyunsaturated fatty acids (n-3 LCPUFAs) are precursors to specialized proresolving mediators that mediate the resolution of inflammation. Our primary hypothesis is that a high supplementation of n-3 LCPUFAs will lower the prevalence and severity of OIPN. METHODS: The OxaNeuro project is an investigator-initiated, multicenter, double-blinded, randomized, placebo-controlled clinical study. We will include 120 patients eligible to receive adjuvant oxaliplatin after colorectal cancer surgery. Patients will receive fish oil capsules containing n-3 LCPUFAs or corn oil daily for 8 months. The primary endpoint is the prevalence of OIPN at 8 months defined as relevant symptoms, including one of the following: abnormal nerve conduction screening, abnormal vibration threshold test, abnormal skin biopsy, or abnormal pinprick test. Additional endpoints include the intensity and severity of OIPN-related neuropathic pain, patient-reported OIPN symptoms, quality of life, mental health symptoms, body composition, and cognitive evaluation. Furthermore, we will evaluate inflammatory biomarkers in blood samples and skin biopsies, including the potential OIPN biomarker neurofilament light protein (NfL) which will be measured before each cycle of chemotherapy. DISCUSSION: If readily available fish oil supplementation alleviates OIPN prevalence and severity, it will significantly improve the lives of both cancer survivors and palliative cancer patients receiving oxaliplatin; it will improve their quality of life, optimize chemotherapeutic treatment plans by lowering the need for dose reduction or premature cessation, and potentially increase survival. TRIAL REGISTRATION: ClinicalTrial.gov identifier: NCT05404230 Protocol version: 1.2, April 25th. 2023.

Impact of Pain on Symptom Burden in Chemotherapy-Induced Peripheral Neurotoxicity.

BACKGROUND: Chemotherapy-induced peripheral neurotoxicity (CIPN) affects the quality of life of cancer survivors. However, the impact of pain on symptom burden remains undefined. This study aimed to define differences in the clinical symptom profile of patients with painful and nonpainful CIPN. PATIENTS AND METHODS: A total of 579 participants (median age, 59 years [IQR, 19 years]; F=66%) were assessed cross-sectionally 6 months posttreatment. CIPN severity was graded using multiple methods, including patient-reported outcome measures, a clinically graded scale (NCI-CTCAE), and a neurologic examination score. Participants were classified into subgroups based on patient symptom report, with painful CIPN characterized by the presence of shooting/burning pain, and nonpainful CIPN characterized by the presence of numbness or tingling without shooting/burning pain. Behavioral changes were assessed via structured patient interview regarding symptom impact on sleep, exercise, and treatment-seeking. RESULTS: Among 579 participants, 24% (n=140) reported painful CIPN, 48% (n=280) reported nonpainful CIPN, and 28% (n=159) had no CIPN. Participants with painful CIPN demonstrated higher CIPN severity than those with nonpainful CIPN across multiple measures, including NCI-CTCAE, neurologic grading, and patient report (all P<.05). Participants with painful CIPN were more likely to report that their symptoms affected their ability to exercise (P=.007), produced sleep impairment, and increased treatment-seeking behavior due to their symptoms (both P<.001) compared with participants with nonpainful CIPN. CONCLUSIONS: Overall, participants with painful CIPN reported higher scores across all CIPN severity measures, including behavioral changes. This study underlines the need for accurate identification of different CIPN subgroups in hopes of informing better treatment and rehabilitation options for cancer survivors with painful CIPN.

Electrodiagnostic reporting preferences of referring physicians: An exploratory survey.

INTRODUCTION/AIMS: Electrodiagnostic (EDX) studies play a crucial role in the evaluation of patients with peripheral nervous system disorders. Accurate and succinct communication of test results is critical to patient safety and clinical decision-making. The objective of this study was to explore EDX reporting preferences of referring physicians to improve quality of communication and patient care. METHODS: An online survey was developed, and a purposive sampling strategy was used to recruit physicians in the authors' professional networks. Quantitative and qualitative survey data underwent frequency and thematic analyses, respectively. RESULTS: There were 40 respondents, including: 21 non-surgical specialists, 12 surgical specialists, and 7 family physicians. Sections rated as most critical were diagnostic impression (97%) and summary/interpretation (72%). Only 18% reported numeric data as critical to their needs, preferring this data to be formatted as bullet points or tables without nerve conduction study waveforms. Regarding the format of the data summary and diagnostic impression sections, the majority of respondents preferred bullet points rather than paragraphs. DISCUSSION: The results of this exploratory survey suggest that physicians who refer patients for EDX studies prefer reports that emphasize the interpretation of EDX data and a clear diagnostic impression, particularly in bullet point format. This project highlights important preferences and how they compare to recommended reporting guidelines, which may help improve communication and ultimately patient care. Future efforts should explore larger sample sizes with all key stakeholders in the EDX process to better understand reporting styles and preferences with greater nuance and context.

Studying serum neurofilament light chain levels as a potential new biomarker for small fiber neuropathy.

BACKGROUND AND PURPOSE: Diagnosing small fiber neuropathies can be challenging. To address this issue, whether serum neurofilament light chain (sNfL) could serve as a potential biomarker of damage to epidermal Aδ- and C-fibers was tested. METHODS: Serum NfL levels were assessed in 30 patients diagnosed with small fiber neuropathy and were compared to a control group of 19 healthy individuals. Electrophysiological studies, quantitative sensory testing and quantification of intraepidermal nerve fiber density after skin biopsy were performed in both the proximal and distal leg. RESULTS: Serum NfL levels were not increased in patients with small fiber neuropathy compared to healthy controls (9.1 ± 3.9 and 9.4 ± 3.8, p = 0.83) and did not correlate with intraepidermal nerve fiber density at the lateral calf or lateral thigh or with other parameters of small fiber impairment. CONCLUSION: Serum NfL levels cannot serve as a biomarker for small fiber damage.

Diagnostic contribution of multi-frequency vibrometry to detection of peripheral neuropathy in type 1 diabetes mellitus compared with nerve conduction studies.

AIM: The aim was to assess the use of multi-frequency vibrometry (MFV) in detecting diabetic peripheral neuropathy (DPN) in type 1 diabetes in comparison to nerve conduction studies (NCS) and neurothesiometer (NT). Our objectives were to examine how VPTs correlated with NCS parameters, evaluate the efficacy of MFV in distinguishing DPN as well as to investigate whether MFV procedure could be based on fewer frequencies. METHODS: Adults with type 1 diabetes with previous MFV examinations were recruited at Skåne University Hospital in Malmö, Sweden, between 2018 and 2020. Participants were examined regarding nerve function in the lower limbs through MFV, NT and NCS. RESULTS: A total of 66 participants (28 women and 38 men) with a median age of 50 (39 to 64) years were included in the study. Through NCS assessment, 33 participants (50%) were diagnosed with DPN. We found negative correlations between VPTs and all NCS parameters, where the strongest correlation was found between sural nerve amplitude and the 125 Hz frequency of MFV. A combination of four frequencies, two low (4 and 8 Hz) and two high (125 and 250 Hz), showed the highest classification efficacy (AUC 0.83, 95% CI 0.73-0.93). CONCLUSION: We conclude that a strong correlation exists between the sural nerve amplitude and the VPTs at 125 Hz and that VPT testing with MFV can be focused on only four frequencies instead of seven, thus shortening test time, to distinguish DPN in the lower limb.

Acquired hyperexcitable peripheral nerve disorders: Clinical and laboratory features, therapeutic responses, and long-term follow-up.

INTRODUCTION/AIMS: Hyperexcitable peripheral nerve disorders (HPNDs) are rare. Although their clinical and laboratory features have been well studied, information on treatment and follow-up is limited. The aim of this study is to explore the long-term clinical, investigative, and therapeutic profile of patients with acquired HPNDs. METHODS: This study retrospectively analyzed patients from a single tertiary care center with HPND (January 2012 to January 2022). Patients were recruited according to published inclusion and exclusion criteria. Details of clinical features, diagnostic tests, therapeutic interventions, and follow-up were recorded. This study included patients with follow-up of 2 or more years. RESULTS: A total of 32 patients (M = 26, F = 6) were studied. The common clinical features included myokymia, neuropathic or shock-like pain, cramps, sleep disturbances, encephalopathy, cerebellar ataxia, and seizures. A total of 81.25% of patients responded favorably to corticosteroids and membrane stabilizers. Among the nonresponders, five received intravenous immunoglobulin (IVIG), and one received plasma exchange (PLEX). Two patients required rituximab due to poor responses to the above treatments. The mean duration of response was 6 weeks (4-24 weeks) from the initiation of treatment. All patients had favorable outcomes, reaching clinical remission within 1-5 years from the initiation of treatment. Only two patients had relapses. Immunotherapy could be stopped in 78% of patients within 3 years and 100% by 5 years. DISCUSSION: Chronic immunosuppression starting with corticosteroids is required for satisfactory outcomes of HPNDs. These disorders usually run a monophasic course, and relapses are uncommon.

Sensory disturbances in Creutzfeldt-Jakob disease.

BACKGROUND: Creutzfeldt-Jakob disease (CJD) is a fatal neurodegenerative disease characterized by rapidly progressive dementia, motor impairments, and psychiatric symptoms. Sensory disturbances were occasionally reported as well. The study aims to describe the sensory symptoms of the disease. METHODS: The CJD Israeli National Database was screened for patients who presented sensory symptoms throughout the disease course. Symptoms, characteristics, and distribution were reviewed and the demographic and clinical data (sex, etiologies of the disease, age of onset, disease duration, neurological exam finding, tau protein level, EEG and MRI findings) were compared with the demographics and clinical data of CJD without sensory symptoms. Then, the patients with sensory symptoms were divided into patients with symptom distribution consistent with peripheral nervous system (PNS) involvement and central nervous system (CNS) involvement. The demographics and clinical data of the 2 groups were compared. RESULTS: Eighty-four CJD patients with sensory symptoms and 645 CJD patients without sensory symptoms were included in the study. Sensory symptoms were more common in genetic E200K CJD patients (14.6% vs. 5.6% respectively, p = 0.0005) (chi-squared test). Numbness and neuropathic pain were the most common symptoms and distribution of symptoms of "stocking gloves" with decreased deep tendon reflexes suggesting peripheral neuropathy in 44% of the patients. In these patients, the classical EEG findings of Periodic Sharp Wave Complexes were less often found (58% vs. 22%, p = 0.02) (chi-squared test). CONCLUSIONS: Sensory symptoms are more common in E200K patients and often follow peripheral neuropathy distribution that suggests PNS involvement.

Epidemiology and Functional Impact of Early Peripheral Neuropathy Signs in Older Adults from a General Population.

INTRODUCTION: Peripheral neuropathy (PN) becomes more common with increasing life expectancy, but general population prevalence estimates are lacking. We investigated an epidemiological distribution of signs of PN among 2,996 community-dwelling participants in Good Aging in Skåne Study, age 60-97, and their impact on physical and autonomic function. METHODS: Signs of PN were measured with Utah Early Neuropathy Scale (UENS). Associations between UENS and physical tests, pain, and dysautonomic phenomena were calculated for each sex, adjusted for age, with estimated marginal means (EMM) and odds ratios (ORs) in four UENS quantiles (Q1-Q4). RESULTS: Participants in Q4 had worse EMM for: time to complete Timed Up and Go test (Q4-Q1: male 10.8-9.6 s; female 11.7-10.2 s), 15 m Walk test (Q4-Q1: male 11.1-9.9 s; female 11.2-10.4 s), and fewer repetitions in Step test (Q4-Q1: male 15.2-17.0 steps; female 14.5-15.8 steps). Higher OR of failing one-leg balance 60 s test {male 2.5 (confidence interval [CI] 95%: 1.7-3.8); female 2.1 (1.1-3.2)}, Foam Pad Balance test (male 4.6 [CI 95%: 3.2-6.7]; female 1.8 [1.3-2.6]), and lower physical quality of life were seen in Q4 compared to Q1. Participants in Q4 had higher OR for walking aid usage, falls, fear of falling, pain, and urinary incontinence, while in males, higher OR for orthostatic intolerance, fecal incontinence, and constipation. CONCLUSIONS: In a general population, 20-25% of older adults who have highest UENS scores, a sensitive measure of early PN, express slower gait, worse balance, lower quality of life, pain, falls and fear of falling, and autonomic symptoms.

Ultrasensitive assay technology and fluid biomarkers for the evaluation of peripheral nerve disease.

The field of biomarker discovery is rapidly expanding. The introduction of ultrasensitive immunoassays and the growing precision of genetic technologies are poised to revolutionise the assessment and monitoring of many diseases. Given the difficulties in imaging and tissue diagnosis, there is mounting interest in serum and cerebrospinal fluid biomarkers of peripheral neuropathy. Realised and potential fluid biomarkers of peripheral nerve disease include neuronal biomarkers of axonal degeneration, glial biomarkers for peripheral demyelinating disorders, immunopathogenic biomarkers (such as the presence and titre of antibodies or the levels of cytokines) and genetic biomarkers. Several are already starting to inform clinical practice, whereas others remain under evaluation as potential indicators of disease activity and treatment response. As more biomarkers become available for clinical use, it has become increasingly difficult for clinicians and researchers to keep up-to-date with the most recent discovery and interpretation. In this review, we aim to inform practising neurologists, neuroscientists and other clinicians about recent advances in fluid biomarker technology, with a focus on single molecule arrays (Simoa), chemiluminescent enzyme immunoassays (CLEIA), electrochemiluminescence (ECL), proximity extension assays (PEA), and microfluidic technology. We discuss established and emerging fluid biomarkers of peripheral neuropathy, their clinical applications, limitations and potential future developments.

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.

Neuropathy Screening for Patients with Peripheral Vascular Disease Helps to Identify Those at an Increased Risk of Amputation, Revascularization, and Death.

BACKGROUND: Peripheral neuropathy is associated with amputation risk among patients with diabetes mellitus and chronic limb-threatening ischemia (CLTI). Detection of peripheral neuropathy may help identify those who are at an increased risk, but the predictive ability of the screening tool used in patients with peripheral arterial disease (PAD) needs to be more clearly defined. METHODS: Patients referred to vascular surgery clinic for PAD were recruited from a single center. Exclusion criteria were a documented history of neuropathy or prior lower limb amputation. Screening utilized the Michigan Neuropathy Screening Instrument (MNSI). Scores >2.5 were considered abnormal and scores >4 were considered positive for peripheral neuropathy. Limb-specific outcomes of amputation and revascularization as well as a composite outcome including death were modeled using time to event analysis. RESULTS: 86 patients were recruited. Mean age was 67 ± 10.2 years, 30% were women, 24% were black. Mean ankle-brachial index was 0.74 ± 0.3. PAD symptoms at initial evaluation were claudication in 52% of patients and CLTI in 38% of patients. Neuropathy was present in 20% of the cohort with a significantly higher proportion in diabetics (34% vs. 3%; P = 0.0009). Neuropathy was more common in patients with CLTI compared to claudicants (36% vs. 9%; P = 0.011). Forty patients (47%) reached the composite outcome of amputation, revascularization, or death with a median time to event of 16 months. Abnormal MNSI examination was significantly associated with the increased risk of the composite outcome (hazard ratio = 3.19; P 0.0005). CONCLUSIONS: A significant proportion of patients presenting to vascular specialists for PAD have undiagnosed neuropathy. Patients with PAD and neuropathy have an increased risk of amputation, revascularization, and death. Expanding neuropathy screening in vascular surgery clinic visits may help to identify patients at higher risk.

Patient perceptions of altering chemotherapy treatment due to peripheral neuropathy.

PURPOSE: Clinical practice guidelines recommend altering neurotoxic chemotherapy treatment in patients experiencing intolerable chemotherapy-induced peripheral neuropathy (CIPN). The primary objective of this survey was to understand patient's perspectives on altering neurotoxic chemotherapy treatment, including their perceptions of the benefits of preventing irreversible CIPN and the risks of reducing treatment efficacy. METHODS: A cross-sectional online survey was distributed via social networks to patients who were currently receiving or had previously received neurotoxic chemotherapy for cancer. Survey results were analyzed using descriptive statistics and qualitative analysis. RESULTS: Following data cleaning, 447 participants were included in the analysis. The median age was 57 years, 93% were white, and most were from the UK (53%) or USA (38%). Most participants who were currently or recently treated expected some CIPN symptom resolution (86%), but 45% of those who had completed treatment more than a year ago reported experiencing no symptom resolution. Participants reported that they would discontinue chemotherapy treatment for less severe CIPN if they knew their symptoms would be permanent than if symptoms would disappear after treatment. Most patients stated that the decision to alter chemotherapy or not was usually made collaboratively between the patient and their treating clinician (61%). The most common reason participants were reluctant to talk with their clinician about CIPN was fear that treatment would be altered. Participants noted a need for improved understanding of CIPN symptoms and their permanence, better patient education relating to CIPN prior to and after treatment, and greater clinician understanding and empathy around CIPN. CONCLUSIONS: This survey highlights the importance of shared decision-making, including a consideration of both the long-term benefits and risks of altering neurotoxic chemotherapy treatment due to CIPN. Additional work is needed to develop decision aids and other communication tools that can be used to improve shared decision making and help patients with cancer achieve their treatment goals.

An up-to-date view of paclitaxel-induced peripheral neuropathy.

Chemotherapy-induced peripheral neuropathy (CIPN),referring to the damage to the peripheral nerves caused by exposure to a neurotoxic chemotherapeutic agent, is a common side effect amongst patients undergoing chemotherapy. Paclitaxel-induced peripheral neuropathy (PIPN) can lead to dose reduction or early cessation of chemotherapy, which is not conducive to patients'survival. Even after treatment is discontinued, PIPN symptoms carried a greater risk of worsening and plagued the patient's life, leading to long-term morbidity in survivors. Here, we summarize the research progress for clinical manifestations, risk factors, pathogenesis, prevention and treatment of PIPN, so as to embark on the path of preventing PIPN with prolongation of patient's life quality on a long-term basis.

Identifying trajectories and predictors of chemotherapy-induced peripheral neuropathy symptoms, physical functioning, and falls across treatment and recovery in adults treated with neurotoxic chemotherapy: the PATTERN observational study protocol (NCT05790538).

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating and dose-limiting side effect of systemic cancer therapy. In many cancer survivors, CIPN persists after treatment ends and is associated with functional impairments, abnormal gait patterns, falls, and diminished quality of life. However, little is known regarding which patients are most likely to develop CIPN symptoms that impair mobility and increase fall risk, when this risk develops, or the optimal timing of early intervention efforts to mitigate the impact of CIPN on functioning and fall risk. This study will address these knowledge gaps by (1) characterizing trajectories of symptoms, functioning, and falls before, during, and after treatment in adults prescribed neurotoxic chemotherapy for cancer; and (2) determining the simplest set of predictors for identifying individuals at risk for CIPN-related functional decline and falls. METHODS: We will enroll 200 participants into a prospective, observational study before initiating chemotherapy and up to 1 year after completing chemotherapy. Eligible participants are aged 40-85 years, diagnosed with stage I-III cancer, and scheduled to receive neurotoxic chemotherapy. We perform objective assessments of vibratory and touch sensation (biothesiometry, tuning fork, monofilament tests), standing and dynamic balance (quiet stance, Timed-Up-and-Go tests), and upper and lower extremity strength (handgrip dynamometry, 5-time repeated chair stand test) in the clinic at baseline, every 4-6 weeks during chemotherapy, and quarterly for 1 year post-chemotherapy. Participants wear devices that passively and continuously measure daily gait quality and physical activity for 1 week after each objective assessment and self-report symptoms (CIPN, insomnia, fatigue, dizziness, pain, cognition, anxiety, and depressive symptoms) and falls via weekly electronic surveys. We will use structural equation modeling, including growth mixture modeling, to examine patterns in trajectories of changes in symptoms, functioning, and falls associated with neurotoxic chemotherapy and then search for distinct risk profiles for CIPN. DISCUSSION: Identifying simple, early predictors of functional decline and fall risk in adults with cancer receiving neurotoxic chemotherapy will help identify individuals who would benefit from early and targeted interventions to prevent CIPN-related falls and disability. TRIAL REGISTRATION: This study was retrospectively registered with ClinicalTrials.gov (NCT05790538) on 3/30/2023.

Development and validation of the chemotherapy-induced peripheral neuropathy integrated assessment - oxaliplatin subscale: a prospective cohort study.

BACKGROUND: Current chemotherapy-induced peripheral neuropathy (CIPN) assessment tools mostly have poor sensitivity and weak anti-interference, so that it is sometimes difficult to provide substantive guidance for clinical intervention. This study aimed to develop an assessment tool dedicated for oxaliplatin to address these limitations. METHODS: This study screened 445 OIPN-related literatures for producing a symptom list, and developed the questionnaire module through expert supplement, item generation, content correlation analysis, pre-testing, and item improvement. The validation phase used a Chinese population-based prospective cohort study from June 2021 to July 2022. Patients were requested to complete the tested questionnaire, QLQ-CIPN20 and the CTCAE grading one day before cycles 2-6 of chemotherapy. Cronbach's α coefficient and intraclass correlation coefficient (ICC) were calculated for the internal consistency and stability analysis, respectively. Exploratory factor analysis was conducted to investigate the construct validity. The correlations among the tested questionnaire, QLQ-CIPN20 and CTCAE were compared for the criterion validity analysis. Wilcoxon signed-rank sum test was utilized to compare the sensitivity between the tested questionnaire and QLQ-CIPN20. RESULT: A 20-item CIPN assessment tool named chemotherapy-induced peripheral neuropathy integrated assessment - oxaliplatin subscale (CIPNIA-OS) was developed. The validation phase included 186 patients. Cronbach's α coefficient of CIPNIA-OS was 0.764 (> 0.7), and ICC was 0.997 (between 0.9 and 1). The structure of CIPNIA-OS containing seven factors was examined. The correlation coefficient between CIPNIA-OS and CTCAE was 0.661 (95%CI 0.623 to 0.695), which was significantly higher than that between QLQ-CIPN20 and CTCAE (0.417, 95%CI 0.363 to 0.469, p < 0.01). Besides, the total score of CIPNIA-OS was mostly higher than QLQ-CIPN20, with an average difference of 2.189 (CI 95% 2.056 to 2.322), and the difference gradually expanded with the progress of chemotherapy (p < 0.05). CONCLUSION: This study developed an original CIPN questionnaire which was dedicated for OIPN assessment. It was a comprehensive tool that covered acute OIPN symptoms and integrated features from several proven CIPN assessment tools. The validation results supported that CIPNIA-OS had satisfactory reliability, stability, construct, criterion validity, and was more accuracy and sensitive than QLQ-CIPN20 in the evaluation of OIPN.

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.