Electrodiagnosis of peripheral neuropathy

Longitudinal Movements and Stiffness of Lower Extremity Nerves Measured by Ultrasonography and Ultrasound Elastography in Symptomatic and Asymptomatic Populations: A Systematic Review With Meta-analysis

This study was aimed at analyzing the effectiveness of ultrasonography (US) and ultrasound elastography (UE) in evaluating longitudinal sliding and stiffness of nerves. In line with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement, we analyzed 1112 publications (range: 2010-2021) extracted from MEDLINE, Scopus and Web of Science focusing on specific outcomes, including shear wave velocity (m/s), shear modulus (kPa), strain ratio (SR) and excursion (mm). Thirty-three papers were included and evaluated for overall quality and risk of bias. From the analysis of data concerning 1435 participants, mean shear wave velocity (SWV) in the sciatic nerve was 6.70 ± 1.26 m/s in controls and 7.51 ± 1.73 m/s in participants presenting with leg pain; in the tibial nerve, mean SWV was 3.83 ± 0.33 m/s in controls and 3.42 ± 3.53 m/s in participants presenting with diabetic peripheral neuropathy (DPN). The mean shear modulus (SM) was 20.9 ± 9.33 kPa for sciatic nerve, whereas it was an average of 23.3 ± 7.20 kPa for the tibial nerve. Considering 146 subjects (78 experimental, 68 controls) no significant difference was observed in SWV when comparing participants with DPN with controls (standard mean difference [SMD]: 1.26, 95% confidence interval [CI]: 0.54, 1.97), whereas a significant difference was observed in the SM (SMD: 1.78, 95% CI: 1.32, 2.25); furthermore, we found significant differences between left and right extremity nerves (SMD:1.14. 95% CI: 0.45, 1.83) among 458 participants (270 with DPN and 188 controls). No descriptive statistics are available for excursion because of the variability in participants and limb positions, whereas SR is considered only a semiquantitative outcome and therefore not comparable among different studies. Despite the presence of some limitations in study designs and methodological biases, on the basis of our findings, we can conclude that US and UE are effective methods in assessing longitudinal sliding and stiffness of lower extremity nerves in both symptomatic and asymptomatic subjects.

Peripheral Neuropathy in Systemic Autoimmune Rheumatic Diseases-Diagnosis and Treatment

Peripheral neuropathy (PN) is frequently observed in systemic rheumatic diseases and is a challenge in clinical practice. We aimed to review the evidence on the subject and proposed a comprehensive approach to these patients, facilitating diagnosis and management. We searched the MEDLINE database for the terms (and its respective Medical Subject Headings (MeSH) terms): "peripheral neuropathy" AND "rheumatic diseases" OR "systemic lupus erythematosus", "rheumatoid arthritis", "Sjogren syndrome", and "vasculitis" from 2000 to 2023. This literature review focuses on the diagnostic workup of PNs related to systemic lupus erythematosus, Sjögren's syndrome, rheumatoid arthritis, and systemic vasculitis. For every type of PN, we provide a pragmatic flowchart for diagnosis and also describe evidence-based strategies of treatment.

Peripheral neuropathy in severe COVID-19 resolved with therapeutic plasma exchange

Peripheral neuropathies including Guillain-Barré syndrome may be linked to life-threatening COVID-19. Plasma exchange is a safe rescue therapy in severe COVID-19 with associated neurological manifestations and thromboinflammation.

Peripheral neuropathy in persons with tuberculosis

Peripheral neuropathy (PN) is a serious condition affecting the nerves that is commonly seen in patients with tuberculosis (TB). Causes of PN in patients with TB are multiple, and can include TB itself, other co-morbid conditions, such as Human Immune-deficiency virus (HIV) disease, malnutrition, or diabetes mellitus (DM), and several anti-tuberculous medications. The condition can manifest with a variety of symptoms, and a diagnosis can usually be made on a clinical basis. Treatment and prognosis of PN vary depending on the underlying cause, but often the condition can lead to permanent disability in individuals with TB. For this reason, primary prevention is key as is early identification and management of symptoms. Treatment can include withdrawal of possible offending agents, vitamin supplementation, physical therapy, analgesics, and targeted agents, including tricyclic antidepressants, selective serotonin reuptake inhibitors, and gabapentin. Additional research is needed to better describe the morbidity and disability associated with PN in persons with TB and to improve management strategies for persons at risk for and affected by this condition. Case review: RM is a 47 year-old man who is in his third month of treatment for drug-resistant TB (DR-TB). His treatment regimen consists of kanamycin (1 gm intramuscular daily), levofloxacin (1000 mg by mouth daily), cycloserine (750 mg by mouth daily), ethionamide (750 mg by mouth daily), pyrazinamide (1500 mg by mouth daily), and Para-Amino Salicylate (12 gm by mouth daily). He is HIV-infected with a CD4 count of 470 cell/µl and on a stable antiretroviral therapy regimen of tenofovir, lamivudine, and efavirenz, which he started 8 weeks ago. He works in a platinum mine, denies smoking, reports drinking beer "on the weekend" and denies other drugs. He presents for his 3 month clinical visit for his DR-TB follow-up and states he is doing well, but he does report some "burning" in the bottom of his feet.

Nerve biopsy findings contribute to diagnosis of multiple mononeuropathy: 78% of findings support clinical diagnosis

Multiple mononeuropathy is an unusual form of peripheral neuropathy involving two or more nerve trunks. It is a syndrome with many different causes. We reviewed the clinical, electrophysiological and nerve biopsy findings of 14 patients who suffered from multiple mononeuropathy in our clinic between January 2009 and June 2013. Patients were diagnosed with vasculitic neuropathy (n = 6), perineuritis (n = 2), chronic inflammatory demyelinating polyradiculoneuropathy (n = 2) or Lewis-Sumner syndrome (n = 1) on the basis of clinical features, laboratory data, electrophysiological investigations and nerve biopsies. Two patients who were clinically diagnosed with vasculitic neuropathy and one patient who was clinically diagnosed with chronic inflammatory demyelinating polyradiculoneuropathy were not confirmed by nerve biopsy. Nerve biopsies confirmed clinical diagnosis in 78.6% of the patients (11/14). Nerve biopsy pathological diagnosis is crucial to the etiological diagnosis of multiple mononeuropathy.

Unilateral peripheral neuropathic pain: The role of neurodiagnostic skin biopsy

According to the current definition of neuropathic pain (“pain arising as a direct consequence of a lesion or disease affecting the somatosensory system”), the demonstration of a lesion or disease involving the somatosensory system is mandatory for the diagnosis of definite neuropathic pain. Although several methods are currently available for this aim, none is suitable for every type of disease (or lesion). Neurodiagnostic skin biopsy (NSB) is a relatively new technique for the diagnosis of peripheral nerve lesions. It is an objective method, completely independent from the patient’s complaining, based on immunohistochemical staining techniques that allow measurement of the density of the epidermal nerve fibers, currently considered the free nerve endings of small diameter (A-delta and C) afferent fibers. NSB has the important property of being used to investigate the skin, allowing obtaining a diagnosis of small fiber axonal neuropathy of peripheral nerves supplying every body part covered by skin. This feature appears to be very important, particularly in cases of unilateral nerve lesions, because it allows going beyond the possibilities of neurophysiological tests which are available only for a limited number of peripheral nerves. All these characteristics make NSB a precious instrument for the diagnosis of peripheral unilateral neuropathic pain.

Timing and appropriate use of electrodiagnostic studies

Electrodiagnostic studies are powerful tools used to objectively examine the physiologic status of a nerve. These consist of nerve conduction studies, which directly examine motor and sensory function of the nerve, and electromyography, which examines spontaneous and voluntary motor unit action potentials in the muscle. Together these studies enable characterization, localization, and duration of nerve pathology. Appropriate timing and use of electrodiagnostic studies assist medical providers in treating nerve pathology.

Electrodiagnostics and clinical correlates in acquired polyneuropathies

Peripheral neuropathies result from a variety of inherited and acquired pathologies. They display an assortment of clinical signs and symptoms and present with a broad range of severity. Electrodiagnosis can play a key role in the evaluation of a suspected peripheral neuropathy. A peripheral nerve disorder is first suspected on the basis of history and physical examination findings. Electrodiagnosis is then used to confirm the diagnosis and to characterize the peripheral neuropathy, providing information about its distribution, pathophysiologic process (demyelinating vs axonal), and chronicity.