Electrophysiological Evidence Of Peripheral Neuropathy Research Articles

Subclinical Neuropathy in Children With Type I Diabetes Mellitus: Tertiary Care Centre Experience.

Introduction: Diabetic peripheral neuropathy is a common complication of diabetes mellitus (DM) type 1. However, it can occur without evidence of symptoms or clinical signs of neuropathy labeled as subclinical neuropathy, which neurophysiological studies can best detect.Purpose: To evaluate the prevalence of subclinical neuropathy among children with DM type 1, determine the association with blood sugar control, and evaluate the pattern of nerve involvement in neurophysiological studies.Methods: This cross-sectional study evaluated 100 children with DM type 1, aged five to 15 years, at least one year after the diagnosis. Subclinical neuropathy was evaluated using nerve conduction study. Glycemic control was assessed using hemoglobin A1c (HbA1c).Results: The mean age of subjects was 11.5 ± 0.25 years. The average age at the onset of the disease was 5.95 ± 0.25 years. There were 64 patients who had electrophysiological evidence of peripheral neuropathy. The most observed electrophysiological changes were distal latency abnormalities in the left and right peroneal nerves in 39 and 33 patients, respectively. Sensory nerve amplitude, peak latency, and conduction velocity were normal in all patients (100%). HbA1c level did not show a statistically significant association with the incidence of subclinical neuropathy.Conclusion: Subclinical neuropathy was prevalent in children with DM type 1. Poor glucose control was only associated with an increased odds ratio of subclinical neuropathy.

Frequency Of Peripheral Neuropathy in Chronic Hepatitis C Patients Presenting at Liaquat University Hospital, Hyderabad

Hepatitis C virus (HCV) and its infective pathogenic role leads to the psychiatric and neurological signs and symptoms. Therefore, close monitoring and regular follow-up is warranted. Objective: To find out the frequency of peripheral neuropathy among patients presenting at Liaquat University Hospital, Hyderabad, having Chronic Hepatitis C. Methods: The cross-sectional study included 359 patients with chronic HCV, aged 20 to 70 years, who presented to the Liaquat University Hospital's Hepatitis Clinic and Outpatient Department of General Medicine and Neurology. Non-probability - sequential sampling was used to choose patients. Patients were asked about demographic information and the duration of chronic HCV after giving informed written consent. The clinical examination was performed to see if there were any reduced tendon reflexes in all of the patient's extremities. To diagnose peripheral neuropathy based on nerve conduction velocity, all patients had an electrophysiological test using a simplified nerve conduction study (NCS) methodology (NCV). The research lasted six months, from June 2021 to December 2021. The information was examined via SPSS version 25.0. Results: There were 219 Men (61%) And 140 Females (39%) among the 359 Patients. The average age (SD) of the participants was 42.3 (8.7) years (range 22–70). HCV infection lasted 36 months on average (range 1–156). Out of 359 patients, 61 had clinical peripheral neuropathy (PN) (17%). Electrophysiological evidence of PN was present in all of these patients, electrophysiological investigation revealed subclinical PN in 19 more patients (5.3%). Conclusion: On the basis of the findings from this study, it can be concluded that a high prevalence of peripheral neuropathy is present among the patients with HCV in our locality. However, an electrophysiological examination should always be done to avoid underestimating PN, particularly in older HCV patients.

Visual evoked potential and nerve conduction study findings in patients recovered from COVID-19.

Objective COVID-19 infection is associated with peripheral neuropathy. However, subclinical neurological involvement may occur anytime, and diagnostic methods that reveal this subclinical involvement are not well established. We aimed to assess the subclinical neurological involvement by visual evoked potential (VEP) measurements and nerve conduction studies (NCS) and explore the relationship between neurological electrophysiological findings and the severity of COVID-19 infection.MethodsSeventy-six patients recovered from COVID-19 infection, and 44 healthy controls were enrolled in the study. Patients were assessed for clinical and demographic parameters. NCS and VEP analyses were performed to detect any peripheral neuropathy or optic neuropathy in both groups.ResultsNone of the COVID-19 patients had electrophysiological evidence of peripheral neuropathy. However, patients with COVID-19 pneumonia had significant abnormalities in several peripheral nerve measurements compared to patients without pneumonia. Although P100 parameters did not differ significantly between patients and controls, 12 patients with COVID-19 had prolonged P100 latencies.ConclusionsWe detected subclinical afferent visual pathway abnormality evaluated by VEP analysis. In addition, we found subtle electrophysiological features in the NCS of the patients presented with COVID-19 pneumonia. However, our findings did not fortify the diagnosis of peripheral neuropathy or optic neuropathy. Further studies are needed to determine the characteristics of COVID-19-related peripheral neuropathy/optic neuropathy whether it has distinct clinical features and disease course.

Peripheral nerve dysfunction and its correlation to interleukin-6 level in obese patients

Abstract Background Obesity is now a worldwide health problem that predisposes to development of numerous complications, one of which is peripheral neuropathy (PN). Elevated interleukin-6 (IL-6) cytokine levels associating the chronic inflammatory state in obesity is thought to play a major role in obesity complications. Methods We conducted a Cross-sectional study on 30 obese patients and 10 matched healthy lean controls. All participants were subjected to full history taking, neurological examination, motor and sensory peripheral nerve conduction studies (NCS). Serum IL-6 levels were assessed using a commercially available ELISA. Laboratory investigations such as glycated haemoglobin, thyroid profile, liver and kidney function tests were done to exclude other known causes of PN. Results Radial, Posterior Tibial and Peroneal nerves had statistically significantly lower motor amplitudes in obese groups compared to control group. Sensory amplitudes of Median nerve showed statistically significant lower values in obese group with PN compared to control group. Conduction velocities (CV) of Ulnar nerve (motor and sensory) and sensory Median nerve showed statistically significant lower CVs in the obese group with PN compared to obese group without PN. Motor Ulnar nerve CV showed highly statistically significant higher velocities in the obese group without PN compared to control group. Posterior Tibial nerve distal motor latencies and Sensory nerve peak latencies of Median nerve had statistically significant higher values in obese group with PN compared to obese group without PN while statistically significant lower sensory peak latencies of Radial nerve were found in obese group without PN compared to control group. Regarding serum IL-6 levels, highly statistically significant higher levels were found in either obese groups when compared to the control group while no statistical significant difference was present between both obese groups and no correlation was found between serum IL-6 and NCS parameters in obese group with PN. Conclusion Our study revealed that despite only 6.667% of our non diabetic obese patients complained of symptoms of PN, by NCS 66.67% of patients were found to have electrophysiological evidence of PN while the remaining 33.33% of patients showed no evidence of PN and no correlation was found between serum IL-6 levels and nerve conduction parameters changes in obese patients diagnosed with PN.

Interstitial amyloidosis in sporadic inclusion body myositis.

Intracellular congophilic inclusions within muscle fibers, although nonspecific, are one of the pathological hallmarks of sporadic inclusion body myositis (sIBM). Extracellular amyloid deposits in muscle, on the other hand, are the canonical findings of amyloid myopathies, which occur with or without systemic amyloidosis. We reviewed the muscle biopsy database (1998-2020) to identify sIBM patients with extracellular amyloid deposits. Clinical and laboratory data were reviewed. We identified five sIBM patients (three clinicopathologically defined and two clinically defined) with extracellular amyloid deposits in muscle. Mean age at diagnosis was 74.8y (range, 68-84 y). All patients had a typical sIBM pattern of weakness without associated sensory or autonomic symptoms. None had electrophysiological evidence of peripheral neuropathy. Only one patient had a monoclonal gammopathy (immunoglobulin M-lambda, IgM-λ) with normal bone marrow biopsy. This patient with monoclonal gammopathy and three other patients underwent abdominal fat pad aspirate and were negative for amyloid. Cardiac evaluation was unrevealing in the four patients tested. Three patients without monoclonal gammopathy had normal transthyretin gene sequencing and inconclusive mass spectrometry-based analysis. The patient with monoclonal gammopathy died of pneumosepsis 5y after diagnosis and autopsy revealed multi-organ transthyretin amyloidosis. Detection of extracellular amyloid deposition in muscle should trigger an aggressive search for systemic amyloidosis independently from other associated myopathological abnormalities. Amyloid subtyping is crucial for early therapy and mortality prevention. An isolated monoclonal gammopathy should not halt a search for non-hematological causes of systemic amyloidosis.

Electrophysiological Characterization of Neuropathy Complicating Type 1 Diabetes Mellitus

Diabetic peripheral neuropathy (DPN) involves sensory and motor nerves, resulting in demyelination as well as axonal degeneration. This study was conducted to describe the pattern of lower limb nerve involvement in children with type 1 diabetes mellitus (DM) based on the parameters of nerve conduction study (NCS). This cross-sectional study recruited 50 children with type 1 DM having mean disease duration of 4.92 ± 3.84 years who attended the referred clinic in Sudan Childhood Diabetes Center. Their mean age was 15.00 ± 2.19 years, 42% were males, and 58% were females. Twenty six matched healthy control subjects were involved; their mean age was 13.88 ± 2.46 years, 38.46% were males, and 61.54% were females. Bilateral NCS of the sensory and motor lower limb nerves was performed using Medelec Synergy machine. Interpretation of the patients' results was based on our own control reference values. Data was analysed using IBM SPSS statistics. Out of the 50 diabetic patients, 44 (88%) had electrophysiological evidence of peripheral neuropathy (abnormalities in at least two of the electrophysiological parameters). The majority (68.2%) had motor involvement and 31.8% had sensorimotor, while none of them (0%) had pure sensory involvement. Regarding abnormal NCS parameters (conduction velocity vs. amplitude of the compound action potential), conduction slowing feature predominated in 61.4% and only few (6.8%) showed amplitude reduction, while 31.8% showed mixed features. The most frequently affected nerve was the common peroneal, followed by posterior tibial, and the least was the sural nerve. The most sensitive parameter was the common peroneal conduction velocity. Motor precedes sensory nerve involvement. The most frequent neurophysiological abnormality was the conduction slowing, and the common peroneal was the most vulnerable nerve. These findings signify generation of a protocol for early screening of neuropathy in children with type 1 diabetes.

Nerve conduction abnormalities in patients with newly diagnosed diabetes mellitus

Background: Peripheral neuropathy is the most common neurologic complication of diabetes mellitus (DM). The incidence of neuropathy increases with increasing duration of diabetes. Diabetes may be preceded by a long period of clinically silent impaired glucose tolerance, altering the nerve function by the time diabetes is diagnosed. Objectives: Assessment of early electrophysiological evidence of peripheral neuropathy in patients with newly diagnosed DM. Materials and Methods: Patients with newly diagnosed type 2 DM within 1 month of detection with or without clinical features of neuropathy were prospectively recruited. Nerve conduction studies were performed on the right upper and lower limbs. Sympathetic skin response and heart rate variability were studied. Results: Twenty-four patients (14 men and 10 women) with newly diagnosed DM were included in the study whose age was 57.66 ± 14.52 years. Eight patients had distal paresthesiae in the lower limbs of whom two had sensory deficit and two had mild motor deficit clinically. Thirteen patients (54.16%) had abnormal sensory conductions and nine patients had abnormal motor conductions. F-wave latencies were significantly prolonged in the upper and lower limbs. Sympathetic skin response was absent in four patients and R-R variation was subnormal in ten patients. Nerve conduction parameters showed correlation with increasing age and hyperglycemia values. Conclusion: Patients with newly detected diabetes have high incidence of clinically manifest and subclinical peripheral neuropathy.

57.: Anti-glutamic acid decarboxylase antibody associated cerebellar ataxia and breast carcinoma

This study aims to highlight the importance of screening for rare causes of acquired ataxia, and present a patient with paraneoplastic anti-Gad antibody cerebellar ataxia. A 79-year-old lady with a past history of Hashimoto’s thyroiditis, spinal ependymoma and noninsulin-dependent diabetes mellitus presented with a 1 month history of gait ataxia. There had been 5 kg unintentional weight loss over several months. Examination revealed gait ataxia without appendicular ataxia, dysarthria, or saccadic eye movement abnormalities. Gaze-evoked nystagmus was intermittently observed. Antineuronal antibodies, tumour markers, vasculitis/antiphospholipid antibody screens, coeliac serology, B12, folate, venereal disease research laboratory, and vitamin E tests were normal or negative. Thyroid-stimulating hormone was mildly elevated with normal T3 and T4 levels. Serum anti-GAD antibody levels were strikingly elevated (>2000 international units/ml). Cerebrospinal fluid (CSF) revealed 4 mononuclear cells. CSF oligoclonal bands were present. Nerve conduction studies did not reveal electrophysiological evidence of peripheral neuropathy. MRI/MR angiography of the brain revealed moderately severe microvascular ischaemic gliosis. MRI of the spine was unremarkable. CT scan of the chest, abdomen and pelvis did not reveal evidence of malignancy. Positron emission tomography scan revealed irregular fluorodeoxyglucose uptake in the thyroid gland and tissues of the right breast. Mammogram revealed three suspicious lesions in the right breast. Biopsy followed by wide local excision revealed invasive tubular carcinoma and low grade ductal carcinoma in situ. Intravenous immunoglobulin G was commenced 4 weeks prior to starting chemotherapy with letrozole. There was a significant improvement in gait ataxia 2 weeks after the second course of Intravenous immunoglobulin G. Anti-GAD antibody associated ataxia is well described, and cases usually respond to immunotherapy. An association with breast cancer has rarely been reported. This case suggests the importance of screening for an underlying malignancy in patients with anti-GAD antibody associated cerebellar ataxia.

Peripheral neuropathy in cystic fibrosis: A prevalence study

Information on peripheral neuropathy in children with cystic fibrosis is scanty. The etiology can be multifactorial (micronutrient deficiency, chronic hypoxia, impaired glucose tolerance, immunological, vasculopathic, critical illness). Forty five cystic fibrosis children aged 1-18 years on vitamin E supplementation for at least 6 months underwent detailed neurological examination, serum vitamin E, vitamin B12, folate, copper levels and detailed nerve conduction studies. The mean age of the study population was 8.35 years (±4.9 years) with 62.2% being males. Overall 22 out of 45 (48.88%,CI: 33.7-64.2) had electrophysiological evidence of peripheral neuropathy which was predominantly axonal (86.4%), sensory (50%), and polyneuropathy (95.45%). There was no significant association between status of serum micronutrients and electrophysiological evidence of peripheral neuropathy. Patients with cystic fibrosis have electrophysiological evidence of peripheral neuropathy (predominantly axonal, sensory and polyneuropathy). There is significant association of higher chronological age with occurrence of peripheral neuropathy.

Resistance of the Peripheral Nervous System to the Effects of Chronic Canine Hypothyroidism

Hypothyroidism has been implicated in the development of multiple peripheral mono- and polyneuropathies in dogs. The objectives of this study were to evaluate the clinical and electrophysiologic effects of experimentally induced hypothyroidism on the peripheral nervous system of dogs. Chronic hypothyroidism will induce peripheral nerve sensorimotor dysfunction. Eighteen purpose-bred, female dogs. Prospective, longitudinal study: Hypothyroidism was induced by radioactive iodine administration in 9 dogs, and the remaining 9 served as untreated controls. Neurological examinations were performed monthly. Electrophysiologic testing consisting of electromyography (EMG); motor nerve conduction studies of the sciatic-tibial, radial, ulnar, and recurrent laryngeal nerves; sciatic-tibial and ulnar F-wave studies; sensory nerve conduction studies of the tibial, ulnar, and radial nerves; and evaluation of blink reflex and facial responses were performed before and 6, 12, and 18 months after induction of hypothyroidism and compared with controls. Clinical evidence of peripheral nervous dysfunction did not occur in any dog. At 6 month and subsequent evaluations, all hypothyroid dogs had EMG and histologic evidence of hypothyroid myopathy. Hypothyroid dogs had significant (P<or=.04) decreases in ulnar and sciatic-tibial compound muscle action potentials over time, which were attributed to the concurrent myopathy. No significant differences between control and hypothyroid dogs were detected in electrophysiologic tests of motor (P>or=.1) or sensory nerve conduction velocity (P>or=.24) or nerve roots (P>or=.16) throughout the study period, with values remaining within reference ranges in all dogs. Chronic hypothyroidism induced by thyroid irradiation does not result in clinical or electrophysiologic evidence of peripheral neuropathy, but does cause subclinical myopathy.

Peripheral neuropathy in patients with primary antiphospholipid (Hughes’) syndrome

The involvement of the peripheral nervous system in diverse autoimmune diseases is well established. However, no appropriately designed studies have been performed in primary antiphospholipid syndrome (PAPS)-related peripheral neuropathy. We aimed to investigate the occurrence of peripheral neuropathy in patients diagnosed with PAPS. Twenty-six consecutive patients with PAPS (Sapporo criteria) and 20 age- and gender-matched healthy controls were enrolled at two referral centers. Exclusion criteria were secondary causes of peripheral neuropathy. A complete clinical neurologic exam followed by nerve conduction studies (NCS) was performed. Paresthesias were reported in eight patients (31%). Objective mild distal weakness and abnormal symmetric deep tendon reflexes were observed in three patients (11.5%). With regard to the electrophysiologic evidence of peripheral neuropathy, nine patients (35.0%) had alterations: four (15.5%) had pure sensory or sensorimotor distal axonal neuropathy (in two of them a carpal tunnel syndrome was also present) and one (4%) had sensorimotor demyelinating and axonal neuropathy involving upper and lower extremities, while four patients (15.5%) showed isolated carpal tunnel syndrome. Clinical and serologic results were similar in all the patients with PAPS, regardless of the presence of electrophysiologic alterations. In conclusion, peripheral neuropathy is a common asymptomatic abnormality in patients with PAPS. The routine performance of NCS may be considered when evaluating such patients.

Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 37

In chronic hepatitis C virus (HCV) infection there is high prevalence of numerous extrahepatic manifestations. Peripheral neuropathy (PN), in the form of symmetric polyneuropathy, asymmetric polyneuropathy, and multineuropathy, may be associated also with HCV infection and is usually related to mixed cryoglobulinemia (CG). However, some HCV+ patients with PN without CG were recently reported, suggesting a possible direct role of HCV in the pathogenesis of PN. From January 2000 to December 2002 we studied 50 HCV+ patients: 21 with symptomatic CG and 29 with chronic HCV without symptomatic CG (23 without CG, 5 with asymptomatic CG). Particular care was taken to exclude other possible causes of PN. Patients without symptomatic CG were examined before starting combined therapy with interferon‐alpha and ribavirin, if needed. Fifteen patients with symptomatic CG had axonal sensorimotor polyneuropathy, 6 axonal sensorimotor multineuropathy or asymmetric polyneuropathy. Six HCV+ patients had other causes of PN (1 CIDP, 2 diabetes, 1 CIDP and diabetes, 1 alcoholism, 1 paraneoplastic with anti‐Hu antibodies). No HCV+ patients without (symptomatic) CG or other possible causes of PN showed clinical and electrophysiological evidence of PN. Our study casts doubts on the existence of a PN directly caused by HCV and suggests that finding a PN in a HCV+ patient without CG should prompt to search for a different cause of PN.

AAEM minimonograph #44: Diseases associated with motor unit activity

Stiff-man syndrome is due to hyperexcitability of anterior horn cells, possibly related to interference with the synthesis or action of gamma-aminobutyric acid. Unexpected acoustic and exteroceptive stimuli produce exaggerated muscle responses. Needle electrode examination of involved muscles yields nonspecific findings and demonstrates involuntary motor unit activity. The appearance and firing pattern of motor units are normal except that agonist and antagonist muscles may contract concurrently. Continuous muscle fiber activity (Isaacs' syndrome) comprises a heterogeneous group of hereditary and acquired disorders that cause hyperexcitability of peripheral nerves. Some are associated with electrophysiologic evidence of peripheral neuropathy and some are not. Repetitive afterdischarges often follow the M-, H-, and F-waves. Needle electrode examination reveals an abnormal pattern of motor unit firing, consisting of myokymic discharges, doublets and multiplets, neuromyotonic discharges, and fasciculations. These abnormalities may occur alone or in combination.

SYMPATHETIC SKIN RESPONSE AND R-R INTERVAL VARIATION IN RHEUMATOID ARTHRITIS

Autonomic nervous system involvement with peripheral neuropathy is a well known complication of rheumatoid arthritis (RA). In the assessment of autonomic function of patients with rheumatoid arthritis, we performed sympathetic skin response (SSR) and R-R interval variation (RRIV) tests in 30 patients and in 30 normal controls. Of 30 patients, 5 had complaints of clinical dysautonomic symptoms. SSRs were abnormal in 6 of 30 patients, whereas 8 showed abnormal RRIVs during deep breathing. Nine of 30 patients also showed electrophysiologic evidence of peripheral neuropathy. All 5 of the patients with clinical dysautonomic symptoms showed abnormal SSR and RRIV test results. No patients with normal results on both tests had clinical dysautonomia. This study showed that there are frequent abnormalities in SSR and RRIV tests in patients with rheumatoid arthritis whether there is a clinical symptom of autonomic dysfunction or not.

Restless legs syndrome and nocturnal myoclonus: initial clinical manifestation of familial amyloid polyneuropathy.

Restless legs syndrome was the first isolated clinical manifestation in four siblings of a family with familial amyloid polyneuropathy. Clinical and electrophysiological evidence of peripheral neuropathy appeared after a variable time interval. Polysomnography showed abnormal sleep patterns and nocturnal myoclonus in all patients. The restless legs syndrome responded favourably to clonazepam.

Prevalence of complications among second-generation Japanese-American men with diabetes, impaired glucose tolerance, or normal glucose tolerance.

In a study sample of 229 second-generation Japanese-American (Nisei) men, 79 with normal glucose tolerance, 72 with impaired glucose tolerance (IGT), and 78 with non-insulin-dependent diabetes, we have determined prevalence rates for certain conditions (ischemic heart disease, peripheral vascular disease, hypertension, retinopathy, neuropathy, and nephropathy) associated with diabetes. All subjects participated in a 75-g oral glucose tolerance test. World Health Organization (WHO) diagnostic criteria and information from the subject's medical history and personal physician were used to classify the subjects. Retinopathy was observed only in diabetic men in the study sample (11.5% of diabetic men). Furthermore, it was observed only in men who were receiving drug treatment for diabetes--40.0% of insulin-treated and 17.2% of sulfonylurea-treated men. Electrophysiologic evidence of peripheral neuropathy was observed in 46.2% of diabetic men and in 4.0% of nondiabetic (normal and IGT) men. For diabetic men with fasting serum glucose greater than or equal to 140 mg/dl, 63.8% had peripheral neuropathy and 19.1% had retinopathy, whereas for diabetic men with fasting serum glucose less than 140 mg/dl, 19.4% had neuropathy and none had retinopathy. For diabetic men with a diabetes duration of greater than or equal to 10 yr, 72.7% had neuropathy and 31.8% had retinopathy; with a diabetes duration of 5-9 yr, 70.6% had neuropathy and 11.8% had retinopathy; and with a diabetes duration of less than 5 yr, 20.5% had neuropathy and none had retinopathy. Nephropathy was distinctly uncommon, and among the measurements of kidney function, only proteinuria was clearly abnormal with diabetes. Prevalence rates of hypertension, peripheral vascular disease, and ischemic heart disease were highest in Nisei men with diabetes, lowest in men with normal glucose tolerance, and intermediate in men with IGT.(ABSTRACT TRUNCATED AT 250 WORDS)

"Painful legs and moving toes" associated with polyneuropathy.

Three patients showing clinical and electrophysiological evidence of peripheral neuropathy also suffered from the syndrome of "painful legs and moving toes". Polygraphic recordings during wakefulness and sleep were consistent with the hypothesis that pathological afferent discharges arising peripherally may induce, via the spinal cord, motor excitation and pain. A severe disruption of the pattern of sleep was found in all cases.

Association of isolated adrenocorticotropin deficiency with a variety of neuro-somatic abnormalities in congenital facial diplegia (Moebius) syndrome.

A male patient with recurring episodes of hypoglycemic attacks was diagnosed as having isolated ACTH deficiency as well as renal glycosuria and ichthyosis vulgaris. In addition, he had facial diplegia and abducens palsy consistent with Moebius syndrome, muscle atrophy with proximal dominancy, high arched palate, hammer toes, and mental retardation. There was electrophysiological evidence of peripheral neuropathy. Muscle biopsy of the deltoid showed mild myofiber atrophy with occasional cylindrical laminated bodies. The association of these disorders has never been reported and it could be coincidental. However, considering the high rate of association of isolated hypogonadotropic hypogonadism and Moebius syndrome with peripheral neuropathy, the present case may indicate a causal relationship between isolated ACTH deficiency and Moebius syndrome, reflecting the disorders in the organ systems derived from a common ectoderm.