Abnormal Nerve Conduction Research Articles

Electrophysiological features of chronic inflammatory demyelinating polyradiculoneuropathy associated with IgG4 antibodies targeting neurofascin 155 or contactin 1 glycoproteins

ObjectiveChronic inflammatory demyelinating polyradiculoneuropathies (CIDP) with antibodies against neurofascin 155 (Nfasc155) or contactin-1 (CNTN1) have distinctive clinical features. Knowledge on their electrophysiological characteristics is still scarce. In this study, we are investigating whether these patients have specific electrophysiological characteristics. MethodsThe electrophysiological data from 13 patients with anti-Nfasc155 IgG4 antibodies, 9 with anti-CNTN1 IgG4 antibodies were compared with those of 40 consecutive CIDP patients without antibodies. ResultsAll the patients with antibodies against Nfasc155 or CNTN1 fulfilled the EFNS/PNS electrodiagnostic criteria for definite CIDP. There was no electrophysiological difference between patients with anti-CNTN1 and anti-Nfasc155 antibodies. Nerve conduction abnormalities were heterogeneously distributed along nerves trunks and roots. They were more pronounced than in CIDP without antibodies. Motor conduction velocity on median nerve <24 m/s or motor velocity on ulnar nerve <26 m/s or motor distal latency on ulnar nerve >7.4 ms were predictive of positive antibodies against the node of Ranvier with a sensitivity of 59% and a specificity of 93%. ConclusionsMarked conduction abnormalities may suggest the presence of positive antibodies against the node of Ranvier. SignificanceAnti-Nfasc155 and anti-CNTN1 antibodies target the the paranodal axo-glial domain but are associated with nerve conduction abnormalities mimicking a “demyelinating” neuropathy.

Study of Sensory Nerve Conduction Abnormalities in Hypothyroid Patients

Study of Sensory Nerve Conduction Abnormalities in Hypothyroid Patients

Peripheral Neuropathy in de novo Patients with Parkinson's Disease.

PurposeThis study aimed to investigate the prevalence of peripheral neuropathy (PNP) and its related serum metabolites in de novo patients with Parkinson's disease (PD). PNP is a type of frequent comorbidity in PD. Although the administration of levodopa has been described as a presumptive risk factor in its development, few studies have explored its effect on unmedicated PD patients.Materials and MethodsThis study included 105 drug-naïve de novo PD patients. A standardized nerve conduction study (NCS) technique was used to evaluate motor or sensory neuropathy. We analyzed serologic tests including metabolic markers of vitamin B12, homocysteine (Hcy), and uric acid (UA).ResultsWe found abnormal nerve conduction velocity findings in 24 out of 105 total patients. Among them, 20 patients showed a type of combined motor-sensory, while three were a type of pure sensory and one was a pure motor. Nine patients had carpal tunnel syndrome. PD with PNP group demonstrated higher serum levels of Hcy and UA compared to PD without PNP group.ConclusionOur data demonstrated a potential role of Hcy and UA on PNP in de novo patients with PD. These results suggest the contribution of the inherent metabolic pathway in deterioration of the peripheral nervous system in PD.

Overexpression of Sirtuin 1 protein in neurons prevents and reverses experimental diabetic neuropathy.

In diabetic neuropathy, there is activation of axonal and sensory neuronal degeneration pathways leading to distal axonopathy. The nicotinamide-adenine dinucleotide (NAD+)-dependent deacetylase enzyme, Sirtuin 1 (SIRT1), can prevent activation of these pathways and promote axonal regeneration. In this study, we tested whether increased expression of SIRT1 protein in sensory neurons prevents and reverses experimental diabetic neuropathy induced by a high fat diet (HFD). We generated a transgenic mouse that is inducible and overexpresses SIRT1 protein in neurons (nSIRT1OE Tg). Higher levels of SIRT1 protein were localized to cortical and hippocampal neuronal nuclei in the brain and in nuclei and cytoplasm of small to medium sized neurons in dorsal root ganglia. Wild-type and nSIRT1OE Tg mice were fed with either control diet (6.2% fat) or a HFD (36% fat) for 2 months. HFD-fed wild-type mice developed neuropathy as determined by abnormal motor and sensory nerve conduction velocity, mechanical allodynia, and loss of intraepidermal nerve fibres. In contrast, nSIRT1OE prevented a HFD-induced neuropathy despite the animals remaining hyperglycaemic. To test if nSIRT1OE would reverse HFD-induced neuropathy, nSIRT1OE was activated after mice developed peripheral neuropathy on a HFD. Two months after nSIRT1OE, we observed reversal of neuropathy and an increase in intraepidermal nerve fibre. Cultured adult dorsal root ganglion neurons from nSIRT1OE mice, maintained at high (30 mM) total glucose, showed higher basal and maximal respiratory capacity when compared to adult dorsal root ganglion neurons from wild-type mice. In dorsal root ganglion protein extracts from nSIRT1OE mice, the NAD+-consuming enzyme PARP1 was deactivated and the major deacetylated protein was identified to be an E3 protein ligase, NEDD4-1, a protein required for axonal growth, regeneration and proteostasis in neurodegenerative diseases. Our results indicate that nSIRT1OE prevents and reverses neuropathy. Increased mitochondrial respiratory capacity and NEDD4 activation was associated with increased axonal growth driven by neuronal overexpression of SIRT1. Therapies that regulate NAD+ and thereby target sirtuins may be beneficial in human diabetic sensory polyneuropathy.

Prospective Evaluation of Median Nerve Dysfunctions in Patients with a Distal Radius Fracture Treated with Volar Locking Plating.

Background: The aim of this study was to identify the risk factors for median nerve dysfunctions after volar locking plate (VLP) fixation for distal radius fracture (DRF). Methods: We prospectively assessed the incidence of median nerve symptoms (MNS) such as numbness, pain, paresthesia, or hypesthesia in the area innervated by the median nerve and evaluated post-operative nerve conduction (NC) in 91 hands of 121 patients after VLP fixation for DRF. Multivariate logistic regression analysis was conducted to identify factors independently associated with MNS and abnormal NC in the injured wrist. Results: There were 18 cases (20%) of MNS on the injured side, 9 hands (10%) of both MNS and abnormal NC, 11 hands (12%) with only abnormal NC, and 9 hands with only MNS. Sensitivity, specificity, and diagnostic accuracy of abnormal NC for diagnosing MNS were 50%, 86%, and 78%, respectively. Four cases did not respond to conservative treatment and received carpal tunnel release concomitantly with plate removal. Logistic regression examination revealed that volar placement of the plate and short stature were significant independent predictors of MNS, while patient age was the sole independent predictor of abnormal NC. Conclusions: Our study demonstrated that plate prominence, short stature, and age were significant independent risk factors for median nerve dysfunctions after VLP fixation for DRF.

Flail arm syndrome patients exhibit profound abnormalities in nerve conduction: an electromyography study

Flail arm syndrome (FAS) is a rare degenerative disease of the nervous system and a variant of amyotrophic lateral sclerosis (ALS). In the current study, we sought to further delineate electromyographic changes in sensory and motor conduction of the median nerve in four FAS patients and also described one representative case of FAS in a 63-year old Chinese male patient who was admitted because of aggravating limb myasthenia for three months. Electromyography showed that FAS patients exhibited variable electromyographic changes in sensory conduction of the median nerve. Abnormal conduction velocity of the sensory nerve in bilateral median nerves was observed in one patient but normal in two other patients. Two patients had a marked reduction in median sensory nerve action potential amplitude. In addition, one patient showed significant reduction in the conduction velocity and motor nerve action potential amplitude. The latency of motor conduction of bilateral median nerves was markedly prolonged. Furthermore, the incidence rate of the F wave in the right median nerve ranged from 5% to 100%. Furthermore, all four patients exhibited abnormalities in needle electromyography in at least three regions of the four regions examined with massive denervations in large and widened motor units and diminished recruitment of motor units, indicating the simultaneous presence of both acute denervation and chronic nerve regeneration. In conclusion, this is the first detailed study of electromyographic changes in FAS and the findings help improve clinicians’ understanding of this disease and differentiating the diagnoses of FAS from ALS.

Clinical analysis of adult-onset neuronal intranuclear inclusion disease

Neuronal intranuclear inclusion disease (NIID) is characterized by eosinophilic nuclear inclusions (NI) in the nervous systems and the visceral organs. Ante-mortem diagnoses have been made by NI identification in skin biopsy samples based on characteristic corticomedullary junction (CMJ) high intensity in brain diffusion-weighted imaging (DWI). However, the clinical symptoms of NIID are variable. We analyzed 14 (10 sporadic, 4 familial) adult-onset NIID patients with clinical examination, electrophysiological study, brain MRI, cerebrospinal fluid (CSF) biomarker, and skin biopsy. The mean onset-age was 63.8 years. Initial symptoms were consciousness disturbance, memory impairment, gait disturbance, etc. The mean scores of MMSE, Japanese version of Montreal Cognitive Assessment and Frontal Assessment Battery were 20.7/30, 14.2/30 and 9.2/18, respectively. Neurological examination demonstrated hypo-areflexia, miosis and urinary dysfunction. All patients showed abnormal nerve conduction. Thirteen of 14 patients revealed high intensities of CMJ in DWI and leukoencephalopathy with ventricular dilatation and brain atrophy in MRI FLAIR images. In one patient with leukoencephalopathy, DWI high intensity was not detected. The levels of total Tau in CSF were increased in accordance with the grade of DWI high intensity. Skin biopsies from all patients demonstrated that NI immunostained with anti-ubiquitin and anti-p62 antibodies in the sweat gland cells, adipocytes and fibroblasts, were composed of filamentous structure without limiting membrane by electron microscopy. In patients with miosis and hyporeflexia with leukoencephalopathy, NIID should be considered for differential diagnosis even when DWI high intensity is negative. Total Tau in CSF will be a biomarker for progression of NIID.

Evidence of small-fiber neuropathy in neurofibromatosis type 1.

Large-fiber neuropathy is rare in neurofibromatosis type 1, but small-fiber neuropathy has not been studied. Patients with neurofibromatosis type 1 underwent nerve conduction studies for large-fiber assessment. Small-fiber tests included quantitative thermal thresholds, laser Doppler flare imaging, intraepidermal nerve fiber density, and corneal nerve fiber length. Of the 52 patients enrolled, 31 (60%) were female and the mean age was 33.0 ± 12.3 years. Four (8%) patients had abnormal nerve conduction studies. Small-fiber tests were frequently abnormal: thermal thresholds in 7 (13%); laser Doppler flare imaging in 10 (19%); intraepidermal nerve fiber density in 11 (22%); and corneal nerve fiber length in 27 (52%). The mean corneal nerve fiber length was below normative level (10.1 ± 2.7 mm/mm3 ). Small-fiber neuropathy may be common in neurofibromatosis type 1, and should be investigated in symptomatic patients.

Carpal tunnel decompression in patients with normal nerve conduction studies.

Some patients present with typical clinical features of carpal tunnel syndrome despite normal nerve conduction studies. This study compared the preoperative and 1-year postoperative QuickDASH scores in patients with normal and abnormal nerve conduction studies, who underwent carpal tunnel decompression. Of the 637 patients included in the study, 19 had clinical features of carpal tunnel syndrome but normal nerve conduction studies, and underwent decompression after failure of conservative management. Preoperative QuickDASH scores were comparable in both groups (58 vs 54.8). However, there were significant differences between the normal and abnormal nerve conduction study groups in the QuickDASH at 1 year (34.9 vs 21.5) and change in QuickDASH postoperatively (23.1 vs 33.4). Patients with normal nerve conduction studies had comparable preoperative disability scores compared with those with abnormal studies. Although they had a significant improvement in QuickDASH at 1 year, this was significantly less than those with abnormal nerve conduction studies. Level of evidence: III.

Secondary hypokalemic paralysis with bulbar weakness and reversible electrophysiologic abnormalities: A case report and systematic review

Hypokalemic periodic paralysis secondary to distal renal tubular acidosis presenting with prominent bulbar symptoms is extremely rare. The exact pathophysiology by which hypokalemia causes weakness is yet to be elucidated though muscle and nerve membrane hyperpolarization have been hypothesized. The pathophysiology of bulbar involvement in this condition is even more unclear. We report a case presenting as acute flaccid quadriplegia with prominent bulbar symptoms that reversed once potassium levels returned to normal. Serial nerve conduction studies were performed at various potassium levels revealing electrophysiologic abnormalities that corrected with potassium repletion. A systematic review of the literature was also conducted focusing on bulbar symptoms and electrophysiologic findings in hypokalemic periodic paralysis. Nerve conduction abnormalities in this condition are seldom documented, but reports have shown reduced amplitudes of compound motor action potentials and abnormal F-waves during acute attacks of hypokalemic paralysis.

Retroperitoneal schwannoma associated with neuropathic pain and electromyographic and nerve conduction abnormalities: A case report

BackgroundThe retroperitoneal space is an uncommon location for schwannomas. A review of the existing literature revealed that only 0.3–3.2% of these tumors are found in this location. Presenting symptoms, if any, are usually vague and include abdominal discomfort. Neuropathic pain as a presenting symptom is rare. We present the first known report of retroperitoneal schwannoma associated with both neuropathic pain and positive EMG/NCS findings. Case descriptionA 34-year-old woman presented initially with a lump underneath her previous cesarean section incision. She was taken to surgery for the suspected intra-abdominal mass. During surgery she was found to have a retroperitoneal mass associated with a large nerve root, so surgery was aborted and the neurosurgery team was then involved. Pre-operative evaluation revealed neuropathic pain in the distribution of the femoral nerve as well as EMG/NCS findings of femoral neuropathy and denervation. She was thus taken to surgery for resection. Pathology confirmed the diagnosis of retroperitoneal schwannoma. ConclusionsRetroperitoneal schwannomas are usually incidental findings. If there are presenting symptoms they are usually vague abdominal complaints. While there is one report of neuropathic pain associated with retroperitoneal schwannoma, there are no previous reports of neuropathic pain with associated EMG/NCS findings.

2237-PUB: Validation of the Simple Diagnostic Criteria in Japan

Introduction: The simple diagnostic criteria (SDC) proposed by Diabetic Neuropathy Study Group in Japan has been widely accepted in our country. However, the diagnostic ability has not yet been fully validated. In the present study, we examined the usefulness of SDC in diagnosis of diabetic polyneuropathy (DPN). Methods: We evaluated admitted 114 diabetic subjects who were diagnosed as DPN employing three independent decision rules consisting SDC: physical signs and symptoms (PHY), nerve conduction study (NCS), or coefficient of variation of RR interval (CVR-R) on electrocardiogram (CVRR). #1. PHY rule: satisfied any two or more of following three items: the presence of symptoms considered to be due to DPN, the decrease or disappearance of bilateral Achilles tendon reflexes, and decreased vibration in the bilateral medial malleoli. #2. NCS rule: one or more nerve conduction abnormalities in two or more nerves out of 12 peripheral nerves. #3. CVRR rule: less than 2% of CVR-R. The diagnostic accuracy was evaluated using the NCS rule as the reference standard. Result: 1. Ninety-six subjects (84.2%) diagnosed as DPN. The proportions of DPN were 37.7% for PHY, 74.6% for NCS, and 43.9% for CVRR. 2. The diagnostic accuracy of PHY and/or CVRR. Discussion: Diagnosis by NCS showed the highest prevalence. The sensitivity of PHY was improved by a combination with CVRR. DPN can be identified effectively utilizing SDC. Disclosure T. Himeno: None. Y. Shibata: None. H. Shimoda: None. M. Kondo: None. S. Tsunekawa: None. Y. Kato: Speaker's Bureau; Self; Merck &amp; Co., Inc. J. Nakamura: Research Support; Self; Astellas Pharma Inc., Boehringer Ingelheim Pharmaceuticals, Inc., Daiichi Sankyo Company, Limited, Eli Lilly and Company, Japan Tobacco Inc., Kissei Pharmaceutical Co., Ltd., Merck Sharp &amp; Dohme Corp., Novartis Pharmaceuticals Corporation, Novo Nordisk Inc., Ono Pharmaceutical Co., Ltd., Sanofi K.K., Sumitomo Dainippon Pharma Co., Ltd., Taisho Pharmaceutical Co., Ltd., Takeda Pharmaceutical Company Limited. Speaker's Bureau; Self; Astellas Pharma Inc., AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Daiichi Sankyo Company, Limited, Eli Lilly and Company, Kowa Pharmaceu. Co. Ltd., Merck Sharp &amp; Dohme Corp., Mitsubishi Tanabe Pharma Corporation, Novartis Pharmaceuticals Corporation, Novo Nordisk Inc., Ono Pharmaceutical Co., Ltd., Sanofi K.K., Takeda Pharmaceutical Company Limited, Terumo Medical Corporation. H. Kamiya: Speaker's Bureau; Self; Astellas Pharma Inc., Eli Lilly Japan K.K., MSD K.K., Novartis Pharma K.K., Novo Nordisk Oharma Ltd., Ono Pharmaceutical Co., Ltd., Sanofi K.K.

322-OR: Risk Factors for Peripheral and Cardiovascular Autonomic Neuropathy in Type 1 Diabetes: Thirty Years of Follow-Up in DCCT/EDIC

The Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study reported that intensive glucose control as assessed by hemoglobin A1c (HbA1c) reduced the risk of diabetic peripheral neuropathy (DPN) and cardiovascular autonomic neuropathy (CAN) in type 1 diabetes (T1D), with long lasting benefits. We evaluated additional clinical parameters and risk factors that could contribute to the development of DPN and CAN in this cohort. DPN was assessed at three different times and defined as a composite of symptoms, signs, and abnormal nerve conduction studies in ≥2 nerves; CAN was assessed seven different times and defined based on R-R variation, Valsalva maneuver, and postural changes in blood pressure. Generalized estimating equation models were used to evaluate the association of DPN and CAN with individual risk factors over repeated time points spanning 30 years. Among 1,441 DCCT/EDIC participants, 32% developed DPN and 44% developed CAN. Higher mean HbA1c was the most significant risk factor for DPN (OR=1.56 per 1%, 95% CI 1.41,1.72). DPN was also associated with older age (1.43 per 5 years, 95% CI 1.31,1.55), longer duration of T1D, higher albuminuria, β-blocker use, higher mean diastolic blood pressure, and higher HbA1c at DCCT eligibility. CAN was associated (in order) with older age (1.51 per 5 years, 95% CI 1.40,1.63), longer duration of T1D (1.07 per 1 year, 95% CI 1.05,1.10), any sustained microalbuminuria (AER ≥30 mg/24 hour on two consecutive visits), higher mean HbA1c, higher mean and current pulse rate (likely as an indirect measure of CAN), higher mean systolic blood pressure, β-blocker use, any eGFR &amp;lt;60 mL/min/1.73 m2, higher HbA1c at DCCT eligibility, and current cigarette smoking. Higher mean HbA1c was the strongest risk factor for DPN, but not of CAN. These findings help identify patient phenotypes and modifiable risk factors for personalized approaches to neuropathy prevention. Disclosure B. Braffett: None. R. Gubitosi-Klug: None. J.W. Albers: Consultant; Self; Eli Lilly and Company. E.L. Feldman: None. C. Martin: None. N.H. White: None. T.J. Orchard: Consultant; Self; Boehringer Ingelheim International GmbH. M.F. Lopes-Virella: None. P. Raskin: Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Gan &amp; Lee Pharmaceuticals, Novo Nordisk A/S. R. Pop-Busui: Consultant; Self; Novo Nordisk A/S. Research Support; Self; AstraZeneca. Other Relationship; Self; American Diabetes Association. Funding Division of Diabetes Endocrinology &amp; Metabolic Diseases (U01DK094176, U01DK094157); National Eye Institute; National Institute of Neurologic Disorders and Stroke; General Clinical Research Centers Program; Clinical Translational Science Center

Clinical characteristics analyses of multiple myeloma with peripheral neuropathy

Objective To investigate the clinical manifestations and nerve electrophysiological abnormalities of the patients with multiple myeloma peripheral neuropathy (MMPN). Methods The clinical data of 35 patients with MMPN diagnosed in Shanxi Provincial People's Hospital from March 2010 to June 2018 were retrospectively analyzed. All patients received nerve electrophysiology examination, including nerve conductive velocity (NCV) and skin sympathetic response (SSR). Results The most common symptoms of peripheral nerve involvement for MMPN patients were sensory abnormalities (25 cases, 71%), including root pains (3 cases, 9%), pain ablation of the upper or lower limbs (18 cases, 51%), dyskinesia (15 cases, 43%), disappeared or reduced knee or ankle reflex (13 cases, 37%) and automatic sympathetic disorders (20 cases, 57%). Nerve electrophysiological tests showed 29 cases (83%) were involved in abnormal sensory nerve conduction velocity (SCV) or motor nerve conduction velocity (MCV), including 13 cases of upper limb abnormality in NCV, 5 cases of prolonged incubation in upper limb, and 10 cases of decreased amplitude; 8 cases of lower limb abnormality in NCV, 6 cases of prolonged incubation in lower limb, and 4 cases of decreased amplitude. SSR test showed abnormalities were found in 17 patients (49%), including 8 cases of upper limb abnormality in SRR, 2 cases of prolonged incubation in upper limb, and 7 cases of decreased amplitude, 1 case of disappeared waveform; 6 cases of lower limb abnormality in SRR, 1 case of prolonged incubation in lower limb, and 4 cases of decreased amplitude, 2 cases of disappeared waveform; 3 cases of abnormal upper and lower limbs. Conclusions The most common peripheral nerve damages of MM are sock and glove-like sensory ablation, accompanied with the involvement of automatic nerve damage. NCV is the major method to diagnose MMPN, and SSR plays an important role in the detection of sympathetic nerve damage of MMPN. Key words: Multiple myeloma; Peripheral nervous system diseases; Electromyography; Neural conduction; Electrophysiology

Endoscopic carpal tunnel release surgery: a case study in Vietnam

BackgroundThis study aims at investigating the outcome and electrophysiologic recovery of 150 carpal tunnel syndrome hands after single-portal endoscopic surgery.MethodsPatients with the cross-sectional area of the median nerve being 13–15 mm2 on ultrasound or abnormal sensory nerve conduction velocity on EMG are assigned to endoscopic surgery that cuts the decompressing transverse ligament to avoid the emergence of severe symptoms, such as muscular atrophy and loss of hand function.ResultsSingle-portal endoscopic release is a safe and efficacious option for carpal tunnel release. The findings demonstrate encouraging results.ConclusionThe endoscopic carpal tunnel release with the placement of a MicroAire system is a safe and effective method for treating carpal tunnel syndrome.

Clinical polyneuropathy does not increase with prediabetes or metabolic syndrome in the Japanese general population.

Aims/IntroductionThe prevalence of clinical polyneuropathies (ClinPNs) or nerve conduction abnormality (NCA) in the groups stratified by glucose tolerance, individual components of metabolic syndrome (metabolic syndrome [MetS] components: hypertension, dyslipidemia, obesity) and MetS defined by the International Diabetes Federation consensus was investigated in the Japanese general population. Factors associated with ClinPN and NCA were also identified.Materials and MethodsA total of 625 examinees of regional medical checkup programs were recruited to this cross‐sectional study. ClinPNs were diagnosed by the Toronto Consensus. NCA was judged by at least one bilateral abnormality of sural nerve action potential amplitude or conduction velocity measured by a point‐of‐care nerve conduction device (DPNCheck). Clinical factors associated with ClinPNs or NCA were examined by multiple logistic regression analysis. Deteriorating factors of sural nerve action potential amplitude or conduction velocity values were also investigated in participants without diabetes (n = 550).ResultsAs for glucose tolerance, ClinPNs or NCA significantly increased only in known diabetes patients compared with other groups. There was no difference between prediabetes and the normal group. The prevalence of ClinPNs and NCA was not significantly related to MetS or MetS’ components, except for frequent NCA in obesity. The factors significantly associated with both NCA and ClinPNs were smoking and known diabetes. In non‐diabetic participants, aging, tall height and hypertension were significant deteriorating factors of nerve conduction functions.ConclusionsIn Japan, ClinPNs and NCA were increased in known diabetes patients, but did not increase in participants with prediabetes, MetS and MetS’ components. Smoking and known diabetes were factors significantly associated with ClinPNs or NCA. Hypertension might be a modifiable deteriorating factor of nerve function.

Hypertension Contributes to Neuropathy in Patients With Type 1 Diabetes.

BACKGROUNDDiabetic peripheral neuropathy (DPN) can lead to foot ulceration and amputation. There are currently no disease-modifying therapies for DPN. The aim of this study was to determine if hypertension contributes to DPN in patients with type 1 diabetes mellitus (T1DM).METHODSSubjects with T1DM (n = 70) and controls (n = 78) underwent a comprehensive assessment of DPN.RESULTSHypertension was present in 40 of 70 T1DM subjects and 20 of 78 controls. Hypertension was associated with abnormal nerve conduction parameters (P = 0.03 to <0.001), increased vibration perception threshold (P = 0.01) and reduced corneal nerve fiber density and length (P = 0.02) in subjects with T1DM. However, after adjusting for confounding factors only tibial compound motor action potential and nerve conduction velocity were associated with hypertension (P = 0.03) and systolic blood pressure (P < 0.01 to <0.0001). Hypertension had no effect on neuropathy in subjects without diabetes.CONCLUSIONSThis study shows that hypertension is associated with impaired nerve conduction in T1DM. It supports previous small trials showing that angiotensin-converting enzyme inhibitors improve nerve conduction and advocates the need for larger clinical trials with blood pressure lowering agents in DPN.

Cardiac autonomic neuropathy in patients with type 2 diabetes mellitus having peripheral neuropathy: A cross-sectional study

AimsThe aim was to see the frequency of CAN in type 2 diabetes mellitus patients with peripheral neuropathy, and its association with peripheral nerve conduction abnormalities. MethodsA cross-sectional study at BIRDEM was conducted in 62 patients with type 2 diabetes mellitus having electrophysiologically diagnosed peripheral neuropathy. CAN was detected by four clinical tests - heart rate response to deep breathing and valsalva maneuver, blood pressure response to standing and sustained handgrip. ResultThe study showed that all patients had CAN – 14.52% had early, 26.67% had definitive and 59.68% had severe CAN. Patients with severe CAN had significantly reduced nerve conduction velocity and amplitude of peripheral nerves (sural 4.36 ± 12.77 vs 9.65 ± 17.77 m/s, p = 0.009; 2.23 ± 1.89 vs 3.01 ± 2.76 mV, p = 0.001; peroneal 7 ± 4.23 vs 8.53 ± 5.99 mV, p = 0.047; tibial 0.008 ± 0.03 vs 0.026 ± 0.05 mV, p = 0.009) and higher serum triglyceride levels (221.17 ± 120.61 vs 197.76 ± 68.43 mg/dl, p = 0.033). ConclusionDiabetic patients with peripheral neuropathy have CAN, the severity of which increases with worsening neuropathy.

Dysmetabolic neuropathy in children with diabetes type I

Neuropathy is the most frequent symptomatic complication of diabetes. Diabetic polyneuropathy (DPN) is the most common variety of neuropathy, which represents chronic symmetrical sensorimotor polyneuropathy. (DPN) typically begins as a generalized asymptomatic dysfunction of peripheral nerve fibers, which may be revealed by electromyography. However, nerve conduction study (NCS) is a sensitive method for early detecting of peripheral neuropathy. We have performed NCS in 69 children with poorly compensated diabetes type I aged 7-18 y. Study protocol included testing of peripheral motor and sensory nerve conduction velocities (NCVs) and compound motor and sensory nerve action potential amplitudes. We revealed subclinical abnormalities, which were symmetric, suggestive of DPN and reflecting disorders of predominantly motor, rather than sensory nerves. In addition, nerve conduction abnormalities were correlated with high HbA1c level, patient age and disease (diabetes) duration. Poor metabolic control was the most important contributor to abnormal electrophysiological parameters.

Polyneuropathy Associated with Severe Iron Overload and Oxidative Stress in β-Thalassemia Patients.

To investigate the frequency of peripheral neuropathy in patients with β-thalassemia, and to assess its relation to iron overload and oxidative stress. Sixty β-thalassemia patients with mean age of 19 ± 4.9years were recruited. Serum ferritin was quantitatively assessed by enzyme-linked immunoassay and biomarkers of oxidative stress were estimated calorimetrically. Electrophysiological studies using NEMUS 2, Galileu Software were carried out. The patients were separated into two groups: those with abnormal nerve conduction studies (NCS) {Group A; N = 38} and those with normal NCS {Group B; N = 22}. Thirty-eight (63.3%) patients had axonal motor neuropathy as evidenced by abnormal NCS (group A), they showed higher mean serum ferritin (p < 0.01), higher mean malondialdehyde (MDA) (p < 0.01), and lower mean nitrous oxide, total antioxidant capacity, paraoxonase-1 (PON1) (p < 0.01) compared to group B. Bivariate analysis of NCS data demonstrated that abnormal NCS were more frequent in splenectomized patients (p = 0.002), and poorly-chelated patients with serum ferritin ≥ 2000ng/ml (p = 0.001). Significant variables associated with abnormal motor NCS were entered in stepwise regression analysis and only elevated serum ferritin (p = 0.01) was independently associated with abnormal motor NCS (p = 0.02; 95% CI 1.433-51.791). None of the studied patients had sensory neuropathy or myopathy. Peripheral motor neuropathy may occur in β-thalassemia patients at a high frequency, regardless of their age and gender. Severe iron overload may contribute to the pathogenesis of neuropathy. Other factors including chelation therapy, splenectomy, and oxidative stress might have an enhancing effect that couldn't be proved in this study.