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Verma A, Aggarwal S, Garg S, Kaushik S, Chowdhury D. Comparison of Serum Holotranscobalamin with Serum Vitamin B12 in Population Prone to Megaloblastic Anemia and their Correlation with Nerve Conduction Study. Indian J Clin Biochem 2023; 38:42-50. [PMID: 36684489 PMCID: PMC9852371 DOI: 10.1007/s12291-022-01027-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 02/21/2022] [Indexed: 01/25/2023]
Abstract
Early detection of megaloblastic anemia and associated neurological complications is crucial for management. This study was conducted to compare serum holotranscobalamin level with serum vitamin B12 level as early biomarker in people prone to megaloblastic anemia and to evaluate co-relation between these biomarkers and nerve conduction study in study patients. 83 adult patients (Hb > 12 gm/dl) prone to megaloblastic anemia were studied for basic haematological investigations, random blood sugar, thyroid function test, liver function test, kidney function test, serum vitamin B12, serum holotranscobalamin and serum folic acid levels. 45 patients among them underwent nerve conduction studies. All study patients were classified in 6 groups on the basis of risk factors for megaloblastic anemia. 29 patients (34.9%) were on antiepileptic drugs, 26 (31.3%) were chronic alcoholic, 10 patients (12%) each, had malabsorption and ileal tuberculosis, 6 (7.22%) had chronic pancreatitis and 2 (2.4%) had ileal resection. 30 patients (36.14%) had low serum holotranscobalamin, including 7 patients (8.43%) with low serum vitamin B12 level also, unmasking vitamin B12 deficiency in 23 patients (27.7%). 7 patients (8.43%) had mean corpuscular volume (MCV) > 100fL and 8 patients (9.63%) had vitamin B12 deficiency related changes on peripheral smear. Serum vitamin B12 and holotranscobalamin levels were significantly low in patients with peripheral smear changes, with p value 0.039 and 0.041 respectively, while no such association seen with MCV. Subclinical peripheral neuropathy was detected in 18 (40%) out of 45 patients on nerve conduction study. Serum holotranscobalamin levels were significantly lower (p = 0.031) than serum vitamin B12 levels (p = 0.2) in patients with neuropathic changes. Rest investigations and serum folic acid levels were normal in all patients. Holotranscobalamin levels can be considered early and reliable marker for vitamin B12 deficiency and deficiency associated peripheral neuropathy, even in patients who are prone to megaloblastic anemia, and not yet anemic or symptomatic for neuropathy.
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Affiliation(s)
- Abhishek Verma
- Department of Internal Medicine, Maulana Azad Medical College and Associated Hospitals, Delhi, 110002 India
| | - Sunita Aggarwal
- Department of Internal Medicine, Maulana Azad Medical College and Associated Hospitals, Delhi, 110002 India
| | - Sandeep Garg
- Department of Internal Medicine, Maulana Azad Medical College and Associated Hospitals, Delhi, 110002 India
| | - Smita Kaushik
- Department of Biochemistry, Maulana Azad Medical College and Associated Hospitals, Delhi, India
| | - Debashish Chowdhury
- Department of Neurology, Govind Ballabh Pant Institute of Postgraduate Medical Education and Research, Delhi, India
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Jena S, Acharya M. Reference values of dorsal sural sensory nerve action potential: A useful tool to diagnose peripheral neuropathy. MULLER JOURNAL OF MEDICAL SCIENCES AND RESEARCH 2021. [DOI: 10.4103/mjmsr.mjmsr_8_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Alberti P, Rossi E, Argyriou AA, Kalofonos HP, Briani C, Cacciavillani M, Campagnolo M, Bruna J, Velasco R, Cazzaniga ME, Cortinovis D, Valsecchi MG, Cavaletti G. Risk stratification of oxaliplatin induced peripheral neurotoxicity applying electrophysiological testing of dorsal sural nerve. Support Care Cancer 2018; 26:3143-3151. [DOI: 10.1007/s00520-018-4170-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 03/19/2018] [Indexed: 01/23/2023]
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Kural MA, Karlsson P, Pugdahl K, Isak B, Fuglsang-Frederiksen A, Tankisi H. Diagnostic utility of distal nerve conduction studies and sural near-nerve needle recording in polyneuropathy. Clin Neurophysiol 2017; 128:1590-1595. [PMID: 28710923 DOI: 10.1016/j.clinph.2017.06.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 05/16/2017] [Accepted: 06/09/2017] [Indexed: 12/14/2022]
Abstract
OBJECTIVE The electrodiagnosis of polyneuropathy (PNP) may benefit from examination using near-nerve needle technique (NNT) and from inclusion of distal nerves. This study compared the diagnostic utility of distal nerve conduction studies (NCS) and NNT recording. METHODS Bilateral NNT and surface recording of the sural nerve and surface recording of the dorsal sural and medial plantar nerves were prospectively done in 91 patients with clinically suspected PNP. Distal NCS were additionally done in 37 healthy controls. Diagnostic reference standard was the final clinical diagnosis retrieved from the patients medical records after 1-4years. RESULTS The clinical follow-up diagnosis confirmed PNP in 68 patients. Equally high sensitivities of the dorsal sural (72%), medial plantar (75%), and sural nerve with NNT recording (77%) were seen, while the sensitivity of conventional surface recording of the sural nerve was lower (60%). Sural NCS with both NNT and surface recording and dorsal sural NCS showed high specificities (85-95%) and positive predictive values (94-98%), while a lower specificity was seen for the medial plantar nerve (68%). CONCLUSION NCS of distal nerves, especially the dorsal sural nerve, have high diagnostic power equalling sural NNT recording. SIGNIFICANCE The electrodiagnostic evaluation of patients with suspected PNP benefits from NCS of distal nerves.
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Affiliation(s)
- Mustafa Aykut Kural
- Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark
| | - Páll Karlsson
- Danish Pain Research Centre, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Kirsten Pugdahl
- Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark
| | - Baris Isak
- Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark
| | | | - Hatice Tankisi
- Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark.
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Chaudhari SC, Mansukhani KA, Sharma A, Balakrishnan L, Sreenivasan A. Dorsal Sural Sensory Nerve Action Potential: A Study for Reference Values. Ann Indian Acad Neurol 2017; 20:127-131. [PMID: 28615897 PMCID: PMC5470164 DOI: 10.4103/0972-2327.194313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND Dorsal sural sensory nerve action potential (SNAP) could help diagnose early or subclinical peripheral neuropathy. OBJECTIVES To establish reference data for dorsal sural SNAP amplitude, latency, and velocity in healthy participants. MATERIALS AND METHODS A prospective study was conducted in 45 nerves from healthy participants between 18 and 90 years and stratified into three age groups (a = 18-40 years, b = 41-60 years, and c>60 years). StataCorp 12.2 statistical program was used for all statistical analyses. Mean-2 standard deviation was used to generate reference values for the lower limit of amplitude and velocity in each age group. ANOVA with Bonferroni correction was used for intergroup comparisons of amplitude and velocity. Regression analysis was used to compute an equation for the predicted amplitude with age, height, and weight as the covariates. RESULTS The lower limit for amplitude (uv) in Groups a, b, and c was 2.57, 1.97, and 1.01, respectively. The lower limit for velocity (m/s) was 33.6, 32, and 22.8, respectively. Statistical significance was noted between the amplitudes of participants in Groups b and c (P = 0.039) and a and c (P = 0.001). Similarly, velocity was significantly different between Groups b and c (P = 0.04) and a and c (P = 0.008). Age was the covariate with maximum effect on the dorsal sural amplitude. Gender and side-to-side comparison did not show statistical significance for amplitude and velocity measurements. Linear regression analysis of the transformed amplitude gave the predictive equation as (y) =3.338 + age (-0.0167) + height in meters (-0.209) + weight (0.001). CONCLUSION This study provides reference data for dorsal sural SNAP in Indian population stratified by age.
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Affiliation(s)
- Sweta Chetan Chaudhari
- Department of Clinical Neurophysiology, Bombay Hospital Institute of Medical Sciences, Mumbai, Maharashtra, India
| | - Khushnuma Anil Mansukhani
- Department of Clinical Neurophysiology, Bombay Hospital Institute of Medical Sciences, Mumbai, Maharashtra, India
| | - Alika Sharma
- Department of Clinical Neurophysiology, Bombay Hospital Institute of Medical Sciences, Mumbai, Maharashtra, India
| | - Lajita Balakrishnan
- Department of Clinical Neurophysiology, Bombay Hospital Institute of Medical Sciences, Mumbai, Maharashtra, India
| | - Aarthika Sreenivasan
- Department of Clinical Neurophysiology, Bombay Hospital Institute of Medical Sciences, Mumbai, Maharashtra, India
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Brito A, Verdugo R, Hertrampf E, Miller JW, Green R, Fedosov SN, Shahab-Ferdows S, Sanchez H, Albala C, Castillo JL, Matamala JM, Uauy R, Allen LH. Vitamin B-12 treatment of asymptomatic, deficient, elderly Chileans improves conductivity in myelinated peripheral nerves, but high serum folate impairs vitamin B-12 status response assessed by the combined indicator of vitamin B-12 status. Am J Clin Nutr 2016; 103:250-7. [PMID: 26607937 DOI: 10.3945/ajcn.115.116509] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 10/14/2015] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND It is uncertain whether vitamin B-12 supplementation can improve neurophysiologic function in asymptomatic elderly with low vitamin B-12 status or whether folate status affects responses to vitamin B-12 supplementation. OBJECTIVE We assessed the effects of a single intramuscular injection of 10 mg vitamin B-12 (which also contained 100 mg vitamin B-6 and 100 mg vitamin B-1) on vitamin B-12 status and neurophysiologic function in elderly community-dwelling Chileans with low serum vitamin B-12 concentrations who were consuming bread fortified with folic acid. DESIGN A pretreatment and posttreatment study was conducted in 51 participants (median ± SD age: 73 ± 3 y; women: 47%) with serum vitamin B-12 concentrations <120 pmol/L at screening. Vitamin B-12 status was defined by combining vitamin B-12, plasma total homocysteine (tHcy), methylmalonic acid (MMA), and holotranscobalamin into one variable [combined indicator of vitamin B-12 status (cB-12)]. The response to treatment was assessed by measuring cB-12 and neurophysiologic variables at baseline and 4 mo after treatment. RESULTS Treatment increased serum vitamin B-12, holotranscobalamin, and cB-12 (P < 0.001) and reduced plasma tHcy and serum MMA (P < 0.001). Treatment produced consistent improvements in conduction in myelinated peripheral nerves; the sensory latency of both the left and right sural nerves improved on the basis of faster median conduction times of 3.1 and 3.0 ms and 3.3 and 3.4 ms, respectively (P < 0.0001). A total of 10 sensory potentials were newly observed in sural nerves after treatment. Participants with high serum folate at baseline (above the median, ≥33.9 nmol/L) had less improvement in cB-12 (P < 0.001) than did individuals whose serum folate was less than the median concentration (i.e., with a concentration <33.9 nmol/L). CONCLUSION Asymptomatic Chilean elderly with poor vitamin B-12 status displayed improved conductivity in myelinated peripheral nerves after vitamin B-12 treatment and an interaction with folate status, which was detected only with the use of cB-12. This trial was registered at www.controlled-trials.com as ISRCTN02694183.
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Affiliation(s)
- Alex Brito
- USDA/Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA
| | - Renato Verdugo
- Department of Neurological Science, Faculty of Medicine, and
| | - Eva Hertrampf
- Institute of Nutrition and Food Technology, University of Chile, Santiago, Chile
| | - Joshua W Miller
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ; Department of Pathology and Laboratory Medicine, University of California, Davis, CA; and
| | - Ralph Green
- Department of Pathology and Laboratory Medicine, University of California, Davis, CA; and
| | - Sergey N Fedosov
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | | | - Hugo Sanchez
- Institute of Nutrition and Food Technology, University of Chile, Santiago, Chile
| | - Cecilia Albala
- Institute of Nutrition and Food Technology, University of Chile, Santiago, Chile
| | - Jose L Castillo
- Department of Neurological Science, Faculty of Medicine, and
| | - Jose M Matamala
- Department of Neurological Science, Faculty of Medicine, and
| | - Ricardo Uauy
- Institute of Nutrition and Food Technology, University of Chile, Santiago, Chile
| | - Lindsay H Allen
- USDA/Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA;
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Dangour AD, Allen E, Clarke R, Elbourne D, Fletcher AE, Letley L, Richards M, Whyte K, Uauy R, Mills K. Effects of vitamin B-12 supplementation on neurologic and cognitive function in older people: a randomized controlled trial. Am J Clin Nutr 2015; 102:639-47. [PMID: 26135351 PMCID: PMC4548176 DOI: 10.3945/ajcn.115.110775] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 06/05/2015] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Moderate vitamin B-12 deficiency is relatively common in older people. However, there is little robust evidence on the effect of vitamin B-12 supplementation on neurologic and cognitive outcomes in later life. OBJECTIVE We investigated whether vitamin B-12 supplementation benefits neurologic and cognitive function in moderately vitamin B-12-deficient older people. DESIGN We conducted a double-blind, randomized, placebo-controlled trial in 7 general practices in South East England, United Kingdom. Study participants were aged ≥75 y and had moderate vitamin B-12 deficiency (serum vitamin B-12 concentrations: 107-210 pmol/L) in the absence of anemia and received 1 mg crystalline vitamin B-12 or a matching placebo as a daily oral tablet for 12 mo. Peripheral motor and sensory nerve conduction, central motor conduction, a clinical neurologic examination, and cognitive function were assessed before and after treatment. RESULTS A total of 201 participants were enrolled in the trial, and 191 subjects provided outcome data. Compared with baseline, allocation to vitamin B-12 was associated with a 177% increase in serum concentration of vitamin B-12 (641 compared with 231 pmol/L), a 331% increase in serum holotranscobalamin (240 compared with 56 pmol/L), and 17% lower serum homocysteine (14.2 compared with 17.1 μmol/L). In intention-to-treat analysis of covariance models, with adjustment for baseline neurologic function, there was no evidence of an effect of supplementation on the primary outcome of the posterior tibial compound muscle action potential amplitude at 12 mo (mean difference: -0.2 mV; 95% CI: -0.8, 0.3 mV). There was also no evidence of an effect on any secondary peripheral nerve or central motor function outcome, or on cognitive function or clinical examination. CONCLUSION Results of the trial do not support the hypothesis that the correction of moderate vitamin B-12 deficiency, in the absence of anemia and of neurologic and cognitive signs or symptoms, has beneficial effects on neurologic or cognitive function in later life. This trial was registered at www.isrctn.com as ISRCTN54195799.
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Affiliation(s)
- Alan D Dangour
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom;
| | - Elizabeth Allen
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Robert Clarke
- Clinical Trial Service Unit & Epidemiological Studies Unit, University of Oxford, Oxford, United Kingdom
| | - Diana Elbourne
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Astrid E Fletcher
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Louise Letley
- Medical Research Council General Practice Research Framework, London, United Kingdom
| | - Marcus Richards
- Medical Research Council Unit for Lifelong Health and Ageing at University College London, London, United Kingdom; and
| | - Ken Whyte
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Ricardo Uauy
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Kerry Mills
- Department of Clinical Neurosciences, King's College, London, United Kingdom
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Is there an association of vitamin B12 status with neurological function in older people? A systematic review. Br J Nutr 2015. [PMID: 26202329 DOI: 10.1017/s0007114515002226] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Low vitamin B12 status is common in older people; however, its public health significance in terms of neurological manifestations remains unclear. The present systematic review evaluated the association of vitamin B12 status with neurological function and clinically relevant neurological outcomes in adults aged 50+ years. A systematic search of nine bibliographic databases (up to March 2013) identified twelve published articles describing two longitudinal and ten cross-sectional analyses. The included study populations ranged in size (n 28-2287) and mean/median age (range 65-81 years). Studies reported various neurological outcomes: nerve function; clinically measured signs and symptoms of nerve function; self-reported neurological symptoms. Studies were assessed for risk of bias, and results were synthesised qualitatively. Among the general population groups of older people, one longitudinal study reported no association, and four of seven cross-sectional studies reported limited evidence of an association of vitamin B12 status with some, but not all, neurological outcomes. Among groups with clinical and/or biochemical evidence of low vitamin B12 status, one longitudinal study reported an association of vitamin B12 status with some, but not all, neurological outcomes and three cross-sectional analyses reported no association. Overall, there is limited evidence from observational studies to suggest an association of vitamin B12 status with neurological function in older people. The heterogeneity and quality of the evidence base preclude more definitive conclusions, and further high-quality research is needed to better inform understanding of public health significance in terms of neurological function of vitamin B12 status in older people.
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Frigeni B, Cacciavillani M, Ermani M, Briani C, Alberti P, Ferrarese C, Cavaletti G. Neurophysiological examination of dorsal sural nerve. Muscle Nerve 2012; 46:895-8. [DOI: 10.1002/mus.23454] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2012] [Indexed: 11/12/2022]
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Torre CD, Lucchetta M, Cacciavillani M, Campagnolo M, Manara R, Briani C. Reversible isolated sensory axonal neuropathy due to cobalamin deficiency. Muscle Nerve 2012; 45:428-30. [DOI: 10.1002/mus.22319] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Ahmed A, Kothari MJ. Recovery of neurologic dysfunction with early intervention of vitamin B12. J Clin Neuromuscul Dis 2010; 11:198-202. [PMID: 20516808 DOI: 10.1097/cnd.0b013e3181b5e136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A patient developed numbness and tingling in distal extremities with subsequent weakness. Evaluation revealed B12 deficiency. She had evidence of myelopathy on imaging studies and polyneuropathy on electrodiagnostic testing. Treatment with B12 caused remittance of symptoms and resolution/improvement of abnormalities found on the imaging and electrodiagnostic studies. This case demonstrates that early intervention with B12 supplementation can cause reversal of both central and peripheral nervous system dysfunction.
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Affiliation(s)
- Aiesha Ahmed
- Penn State College of Medicine, Hershey Medical Center, Department of Neurology, Hershey, PA 17033, USA
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Allen JM, Greer BJ, Sorge DG, Campbell SE. MR Imaging of Neuropathies of the Leg, Ankle, and Foot. Magn Reson Imaging Clin N Am 2008; 16:117-31, vii. [DOI: 10.1016/j.mric.2008.02.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Løseth S, Nebuchennykh M, Stålberg E, Mellgren SI. Medial plantar nerve conduction studies in healthy controls and diabetics. Clin Neurophysiol 2007; 118:1155-61. [PMID: 17321794 DOI: 10.1016/j.clinph.2007.01.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2006] [Revised: 12/20/2006] [Accepted: 01/14/2007] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To collect a reference material of the medial plantar nerve action potential, to test intra/interobserver reliability in healthy controls and to apply the test to a group of patients with diabetes mellitus. METHODS 98 healthy controls and 50 patients with diabetes mellitus were included. The medial plantar nerve was stimulated orthodromically and recorded with a surface electrode. In the patient group, NCS of motor and sensory nerves and quantitative sensory testing were also performed. RESULTS Responses of the medial plantar nerve were obtained from all controls except from one aged 72. Amplitude decreased with age (r=-0.68, p<0.0001). Intra/interobserver reliability was acceptable. 52% of the patients had abnormal overall NCS classification. Forty-eight percent had delayed tibial F-response latency. The medial plantar NCS were abnormal in 59% of the cases (47% abnormal NAP amplitude and 39% reduced CV), 59% of those with abnormal NCS had symptoms of sensory polyneuropathy. Only 24% had abnormal sural amplitude. Cold perception threshold was abnormal in more patients (30%) than warmth perception threshold (14%). CONCLUSIONS Responses were easily obtained in controls under 70 years. In diabetics the amplitudes of the medial plantar nerve were abnormal more often than in the sural nerve. SIGNIFICANCE The medial plantar nerve response is reliable in patients under 70 years, and intra/interobserver reliability is acceptable.
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Affiliation(s)
- Sissel Løseth
- Department of Neurology, Institute of Clinical Medicine, University of Tromsø and University Hospital of North Norway, Tromsø, Norway.
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