vitamin-b-12 and Polyneuropathies

The prevalences of polyneuropathy and epilepsy are higher in people living with Parkinson's disease (PwPD) when compared to older adults. Vitamin B6 is widely available and affordable. PwPD are at higher risk of having abnormal serum levels of vitamin B6, which are associated with polyneuropathy and epilepsy that are potentially preventable and treatable. Potential contributors to abnormal B6 levels in PwPD include age, dietary habits, vitamin supplement misuse, gastrointestinal dysfunction and complex interactions with levodopa. The literature on the potential consequences of abnormal B6 levels in PwPD is limited by a small number of observational studies focused on polyneuropathy and epilepsy. Abnormal B6 levels have been reported in 60 of 145 PwPD (41.4% relative frequency). Low B6 levels were reported in 52 PwPD and high B6 levels were reported in 8 PwPD. There were 14 PwPD, polyneuropathy and low B6. There were 4 PwPD, polyneuropathy and high B6. There were 4 PwPD, epilepsy and low B6. Vitamin B6 level was low in 44.6% of PwPD receiving levodopa-carbidopa intestinal gel and in 30.1% of PwPD receiving oral levodopa-carbidopa. In almost all studies reporting low B6 in PwPD receiving oral levodopa-carbidopa, the dose of levodopa was ≥1000 mg/day. Rigorous epidemiological studies will clarify the prevalence, natural history and clinical relevance of abnormal serum levels of vitamin B6 in PwPD. These studies should account for diet, vitamin supplement use, gastrointestinal dysfunction, concurrent levels of vitamin B12, folate, homocysteine and methylmalonic acid, formulations and dosages of levodopa and other medications commonly used in PwPD.

Topics: Aged; Antiparkinson Agents; Carbidopa; Epilepsy; Humans; Levodopa; Parkinson Disease; Polyneuropathies; Vitamin B 12; Vitamin B 6; Vitamins

Nitrous oxide (NO) is a commonly used drug in medical practice, restoration, and the automobile industry. Recreational abuse is an emerging public health problem owing to its accessibility and drug properties.. A 25-year-old male was hospitalized with acute psychosis and lower-extremity sensorimotor proprioceptive ataxia due to nitrous oxide abuse.. Laboratory studies confirmed a vitamin B12 deficiency. Magnetic resonance imaging of the spinal cord showed normal findings. Electrophysiological testing confirmed length-dependent sensorimotor polyneuropathy, with a predominant motor component and axonal degeneration.. Abstinence from toxic substances was suggested, and vitamin B12 substitution was introduced. The patient was lost to follow up.. Nitrous oxide toxicity is multisystemic and is thought to result from vitamin B12 inactivation. Recent case reports postulated direct paranodal lesions resulting from nitrous oxide consumption. Neurological, neuropsychiatric, and hematological toxicities are among those explored in this case report. Correction of the functional vitamin B12 status and nitrous oxide abstinence are essential in the treatment process.

Topics: Adult; Graft vs Host Disease; Humans; Male; Nitrous Oxide; Polyneuropathies; Psychotic Disorders; Vitamin B 12; Vitamin B 12 Deficiency

Patients with Parkinson's disease (PD) treated with oral levodopa have a higher prevalence of chronic, prevalently sensory, usually mild axonal polyneuropathy (PNP). Several studies showed a positive association among PNP, cumulative levodopa dosage, low serum B12 and high-homocysteine and methylmalonic acid level. Anecdotal severe acute or subacute PNPs thought to be Guillain-Barré syndrome have been reported in patients receiving continuous intraduodenal infusion of levodopa/carbidopa intestinal gel (LCIG). We report an additional acute case and by a systematic literature search we also reviewed the clinical and laboratory features of 13 other acute and 21 subacute PNP cases occurring during LCIG treatment. In series with at least nine patients, the mean frequency of acute and subacute PNP is 13.6% and the mortality rate at 6 months in acute cases is 14%. The great majority of PNP cases displayed axonal sensory-motor and reduced vitamin B12 levels, and alterations of metabolites of 1-carbon pathway were found in most patients. We discuss the possible role of high-levodopa dosage, vitamin B12, B6 and folate deficiency and accumulation of homocysteine and methylmalonic acid in the pathogenesis to conclude that there is enough, although circumstantial, evidence that alterations of 1-carbon pathway are implicated also in acute and subacute PNP during LCIG usage. There is no solid proof for a dysimmune pathogenesis and in our opinion acute, subacute and chronic PNP, either after oral levodopa or LCIG, represent a continuum. Finally, we propose recommendations for prevention and management of PNP occurring during LCIG treatment.

Topics: Administration, Oral; Carbidopa; Drug Combinations; Female; Gels; Humans; Levodopa; Parkinson Disease; Polyneuropathies; Vitamin B 12

Distal symmetric polyneuropathy (DSP) is the most common variety of neuropathy. Since the evaluation of this disorder is not standardized, the available literature was reviewed to provide evidence-based guidelines regarding the role of laboratory and genetic tests for the assessment of DSP.. A literature review using MEDLINE, EMBASE, Science Citation Index and Current Contents was performed to identify the best evidence regarding the evaluation of polyneuropathy published between 1980 and March 2007. Articles were classified according to a four-tiered level of evidence scheme and recommendations were based upon the level of evidence.. 1. Screening laboratory tests may be considered for all patients with polyneuropathy (Level C). Those tests that provide the highest yield of abnormality are blood glucose, serum B12 with metabolites (methylmalonic acid with or without homocysteine) and serum protein immunofixation electrophoresis (Level C). If there is no definite evidence of diabetes mellitus by routine testing of blood glucose, testing for impaired glucose tolerance may be considered in distal symmetric sensory polyneuropathy (Level C). 2. Genetic testing is established as useful for the accurate diagnosis and classification of hereditary neuropathies (Level A). Genetic testing may be considered in patients with cryptogenic polyneuropathy who exhibit a hereditary neuropathy phenotype (Level C). Initial genetic testing should be guided by the clinical phenotype, inheritance pattern, and electrodiagnostic (EDX) features and should focus on the most common abnormalities which are CMT1A duplication/HNPP deletion, Cx32 (GJB1), and MFN2 mutation screening. There is insufficient evidence to determine the usefulness of routine genetic testing in patients with cryptogenic polyneuropathy who do not exhibit a hereditary neuropathy phenotype (Level U).

Topics: Blood Protein Electrophoresis; Clinical Laboratory Techniques; DNA Mutational Analysis; Evidence-Based Medicine; Glucose Tolerance Test; Humans; Inheritance Patterns; Polyneuropathies; Vitamin B 12

Topics: Alcoholism; Anticonvulsants; Cyanides; Deficiency Diseases; Electroencephalography; Erythrocytes; Folic Acid Deficiency; Humans; Isoniazid; Nervous System Diseases; Neurocognitive Disorders; Pellagra; Polyneuropathies; Schilling Test; Spinal Cord Diseases; Thiamine Deficiency; Transketolase; Tryptophan; Vitamin B 12; Vitamin B 12 Deficiency; Vitamin B 6 Deficiency; Vitamin B Deficiency; Wernicke Encephalopathy

This study was designed to determine the prevalence of definite vitamin B(12) deficiency (defined as < or =240 pg/ml) and possible vitamin B(12) deficiency (defined as >240 pg/ml and a methylmalonic acid [MMA] level >243 nmol/L) in patients with polyneuropathy and to determine whether patients in both groups respond to vitamin B(12) repletion. We performed a retrospective cohort study of 581 patients presenting with polyneuropathy over a 2-year period; 4% had definite vitamin B(12) deficiency and 32% had possible deficiency as the sole or contributing cause for their polyneuropathy. For those who received treatment with vitamin B(12), subjective improvement was seen in 87% with definite and in 43% with possible deficiency. Possible vitamin B(12) deficiency, defined as an elevated MMA level, is a common finding in patients with polyneuropathy and treatment of these patients with vitamin B(12) may lead to clinical improvement.

Topics: Cohort Studies; Female; Humans; Male; Methylmalonic Acid; Polyneuropathies; Retrospective Studies; Vitamin B 12

High-flux haemodialysis (HD) has recently been vigorously promoted as a novel standard, and it can indeed efficiently reduce the occurrence of most uraemic symptoms due to middle molecular toxins and/or underdialysis. However, some symptoms remain problematical, particularly peripheral polyneuropathy (PPN). One of the possible reasons for this is that the patients may have low concentrations of some nutrients, e.g. vitamin B(6), necessary for normal peripheral neuron function.. Predialysis serum pyridoxal-5'-phosphate (P5P) level was determined in 36 chronic HD patients who were undergoing high-flux HD and receiving human recombinant erythropoietin. Among them, 26 patients suffered from PPN. Prior to supplementation, these 26 patients were examined and their neurological symptoms were ranked according to our PPN symptom score. Vitamin B(6) (60 mg/day) was randomly prescribed to 14 of them, and vitamin B(12) (500 microg/day) was prescribed to the others. After 4 weeks, all the patients were re-examined.. We found that predialysis serum P5P levels of HD patients with PPN were not significantly lower than those of matched HD patients without PPN. Nonetheless, it was demonstrated that supplementation with vitamin B(6) for 4 weeks significantly increased the predialysis level of P5P and dramatically attenuated PPN symptoms compared with initial symptoms. No improvement was observed in response to vitamin B(12) supplementation.. This result suggests that although vitamin B(6) deficiency could not be demonstrated in patients with chronic renal failure on high-flux HD, vitamin B(6) supplementation was effective in improving PPN symptoms of various aetiologies, possibly because of vitamin B(6) resistance to PPN in these patients.

Topics: Chronic Disease; Diabetic Neuropathies; Erythropoietin; Female; Glomerulonephritis; Humans; Kidney Failure, Chronic; Male; Middle Aged; Polyneuropathies; Pyridoxal Phosphate; Pyridoxine; Recombinant Proteins; Renal Dialysis; Vitamin B 12

Topics: Follow-Up Studies; Humans; Magnetic Resonance Imaging; Nitrous Oxide; Polyneuropathies; Vitamin B 12; Vitamin B 12 Deficiency

Determine vitamin B12 threshold levels below which additional testing of methylmalonic acid (MMA) and/or homocysteine (Hcy) is useful to diagnose metabolic vitamin B12 deficiency in patients with polyneuropathy, and how vitamin B12, MMA and Hcy levels relate to the effect of supplementation therapy.. In a retrospective cohort study of 331 patients with polyneuropathy, vitamin B12, MMA and Hcy were measured. Linear regression models with vitamin B12 as dependent and Hcy or MMA as covariate were compared, to assess which was best related to vitamin B12. Threshold vitamin B12 levels for metabolic deficiency (defined as elevatede metabolites) were determined using logistic regression with elevated metabolites as dependent and vitamin B12 as covariate. A structured interview was conducted in 42 patients to evaluate response to vitamin B12 supplementation.. MMA was best related to vitamin B12. Using elevated MMA for metabolic deficiency, we found 90% sensitivity at a vitamin B12 threshold level <264 pmol/L (358 pg/mL) and 95% sensitivity at <304 pmol/L (412 pg/mL). Improvement after supplementation was reported by 19% patients and stabilization by 24%. 88% of patients with improvement and 90% with stabilization either had absolute deficiency (Vitamin B12 < 148 pmol/L) or metabolic deficiency (elevated MMA and vitamin B12 ≥ 148 pmol/L). There were no additional patients with improvement or stabilization with isolated elevated Hcy.. Testing of MMA has additional value in identifying patients with clinically relevant metabolic deficiency when vitamin B12 is below 304 pmol/L (412 pg/mL). Supplementation can be effective in patients with absolute and metabolic deficiency.

Topics: Homocysteine; Humans; Methylmalonic Acid; Polyneuropathies; Retrospective Studies; Vitamin B 12; Vitamin B 12 Deficiency

In recent years, an increasing number of people adapt to a vegetarian, pescatarian or flexitarian dietary pattern that reduces the consumption of meat and fish. Although these dietary patterns have a risk for developing vitamin B12 deficiency associated polyneuropathy, it is unknown whether this risk is still increased when vitamin B12 levels are adequate.. To examine whether a vegetarian, pescatarian or flexitarian dietary pattern is associated with an increased risk for idiopathic axonal polyneuropathy.. We conducted a case-control study that included 256 idiopathic axonal polyneuropathy patients with adequate vitamin B12 blood levels and 630 controls. We used questionnaire data to determine the frequency of meat and fish consumption and defined dietary patterns.. The vegetarian (no meat or fish consumption) and the pescatarian (fish consumption, no meat consumption) dietary patterns showed no increased risk of axonal polyneuropathy. Frequency-effect analysis and quantity-effect analysis also did not show that a reduction of meat or fish consumption (flexitarian dietary pattern), either small or large, changed the risk of axonal polyneuropathy.. We did not find an increased risk for axonal polyneuropathy among people with a vegetarian, pescatarian or flexitarian diet and an adequate vitamin B12 level.

Topics: Animals; Case-Control Studies; Diet, Vegetarian; Humans; Polyneuropathies; Vegetarians; Vitamin B 12

Chronic axonal polyneuropathy is a common disease, but the etiology remains only partially understood. Previous etiologic studies have identified clinical risk factors, but genetic evidence supporting causality between these factors and polyneuropathy are largely lacking. In this study, we investigate whether there is a genetic association of clinically established important risk factors (diabetes, body mass index [BMI], vitamin B12 levels, and alcohol intake) with chronic axonal polyneuropathy.. This study was performed within the population-based Rotterdam Study and included 1565 participants (median age = 73.6 years, interquartile range = 64.6-78.8, 53.5% female), of whom 215 participants (13.7%) had polyneuropathy. Polygenic scores (PGSs) for diabetes, BMI, vitamin B12 levels, and alcohol intake were calculated at multiple significance thresholds based on published genome-wide association studies.. Higher PGSs of diabetes, BMI, and alcohol intake were associated with higher prevalence of chronic axonal polyneuropathy, whereas higher PGS of vitamin B12 levels was associated with lower prevalence of polyneuropathy. These effects were most pronounced for PGSs with lenient significance thresholds for diabetes and BMI (odds ratio [OR]. This study provides evidence for polygenic associations of diabetes, BMI, vitamin B12 level, and alcohol intake with chronic axonal polyneuropathy. This supports the hypothesis of causal associations between well-known clinical risk factors and polyneuropathy.

Topics: Aged; Diabetes Mellitus, Type 2; Female; Genome-Wide Association Study; Humans; Male; Polyneuropathies; Risk Factors; Vitamin B 12

Topics: Anemia, Pernicious; Humans; Nitrous Oxide; Polyneuropathies; Vitamin B 12; Vitamins

Testing and prescribing vitamin B12 (also known as cobalamin) is increasing in Switzerland but substantial variation among general practitioners (GPs) with respect to testing has been noted. In this study, we aimed at exploring GPs' mindsets regarding vitamin B12 testing and prescribing. A cross-sectional study was conducted using an online survey distributed by e-mail to Swiss GPs. The questionnaire explored mindsets related to testing and prescribing vitamin B12 in specific clinical situations, as well as testing and prescribing strategies. The questionnaire was sent to 876 GPs and 390 GPs responded (44.5%). The most controversial domains for testing and prescribing vitamin B12 were idiopathic fatigue (57.4% and 43.4% of GPs agreed, respectively) and depressive symptoms (53.0% and 35.4% of GPs agreed, respectively). There was substantial variation among GPs with regard to testing strategies (89.5% of GPS used a serum cobalamin test, 71.3% of GPS used holotranscobalamin, and 27.6% of GPs used homocysteine or methylmalonic acid). Intramuscular injection was the predominantly prescribed route of application (median of 87.5% of the prescriptions). In this study, we focus on discordant mindsets that can be specifically targeted by using educational interventions, and research questions that still need answering specifically about the effectiveness of vitamin B12 for idiopathic fatigue.

Topics: Adolescent; Adult; Anemia; Attitude of Health Personnel; Clinical Laboratory Techniques; Cross-Sectional Studies; Depression; Fatigue; Female; General Practice; General Practitioners; Humans; Male; Physicians; Polyneuropathies; Practice Patterns, Physicians'; Surveys and Questionnaires; Switzerland; Vitamin B 12; Vitamin B 12 Deficiency; Young Adult

A 62-year-old Japanese woman developed numbness of the extremities and megaloblastic anemia. She had undergone total abdominal hysterectomy, whole-pelvis radiation therapy and chemotherapy for gynecological cancer 10 years before. Chronic abdominal pain, diarrhea and intermittent small-bowel obstruction had afflicted her for a long time. We diagnosed her with vitamin B12 deficiency anemia and polyneuropathy due to chronic radiation enteritis causing malabsorption. Vitamin B12 injections improved her numbness and anemia. The early diagnosis and treatment of deficiency of vitamin B12 are important. Physicians should regularly measure vitamin B12 levels and supplement vitamin B12 as needed in patients with chronic radiation enteritis.

Topics: Anemia, Megaloblastic; Enteritis; Female; Gastrointestinal Diseases; Genital Neoplasms, Female; Humans; Hypesthesia; Malabsorption Syndromes; Middle Aged; Polyneuropathies; Radiation Injuries; Vitamin B 12; Vitamin B 12 Deficiency

Topics: Acute Disease; Adult; Diagnosis, Differential; Disease Progression; Homocystinuria; Humans; Male; Polyneuropathies; Vitamin B 12; Vitamin B 12 Deficiency

Nitrous oxide, laughing gas, is used as a party drug to achieve a euphoric effect. It has been gaining popularity in recent years and is considered a relatively innocent substance. Nitrous oxide is known to cause subacute degeneration of the spinal cord by inactivation of active vitamin B12. Vitamin B12 plays an essential role in the synthesis of myelin. Hence, vitamin B12 deficiency can lead to degeneration of the dorsal and lateral columns of the spinal cord. Polyneuropathy is a less known complication. We present a 17-year-old woman and a 19-year-old man with subacute axonal polyneuropathy caused by laughing gas abuse. Abstinence of laughing gas and treatment with intramuscular and oral vitamin B12 suppletion respectively have led to improvement of their symptoms. Our cases demonstrate a less-known but treatable complication of laughing gas.

Topics: Adolescent; Female; Humans; Male; Nitrous Oxide; Polyneuropathies; Spinal Cord Diseases; Vitamin B 12; Vitamin B 12 Deficiency; Young Adult

Continuous jejunal levodopa infusion is an increasingly used therapy option in patients with Parkinson's disease who experience severe fluctuations from oral levodopa. In a number of recent reports polyneuropathy in patients receiving jejunal levodopa infusion was referenced to cobalamin (vitamin B12) deficiency. We describe one of three cases from our hospital with severe subacute polyneuropathy that developed during jejunal levodopa infusion, and occurred despite vitamin substitution therapy and normal vitamin B12 and holotranscobalamin serum levels.

Topics: Aged; Antiparkinson Agents; Carbidopa; Drug Combinations; Humans; Infusions, Parenteral; Jejunum; Levodopa; Male; Parkinson Disease; Polyneuropathies; Vitamin B 12

The rising incidence of diabetes and its negative impact on quality of life highlights the urgent need to develop biomarkers of early nerve damage. Measurement of total vitamin B12 has some limitations. We want to determine the levels of urinary methylmalonic acid and its relationships with serum vitamin B12 and polyneuropathy. The 176 Chinese patients with Type 2 diabetes mellitus were divided into 3 groups according to the levels of vitamin B12. A gas chromatography mass spectrometric technique was used to determine blood methylmalonic acid and urinary methylmalonic acid. The diagnosis of distal diabetic polyneuropathy was based on the determination of bilateral limb sensory and motor nerve conduction velocity and amplitude with electromyogram. Multiple regression analysis revealed that urinary methylmalonic acid/creatinine, blood methylmalonic acid, and so forth were variables that influenced diabetic polyneuropathy significantly. Nerve sensory conduction velocity and nerve amplitude in the group of urinary methylmalonic acid/creatinine >3.5 mmol/mol decreased significantly. Superficial peroneal nerve sensory and motor conduction velocity and ulnar nerve compound motor active potential amplitude were inversely correlated with urinary methylmalonic acid/creatinine. Urinary methylmalonic acid correlates with serum vitamin B12 levels in person with diabetes and is a sensitive marker of early polyneuropathy.

Topics: Adult; Aged; Asian People; Biomarkers; China; Diabetes Mellitus, Type 2; Diabetic Neuropathies; Female; Humans; Male; Methylmalonic Acid; Middle Aged; Motor Neurons; Neural Conduction; Polyneuropathies; Prospective Studies; Sensory Receptor Cells; Severity of Illness Index; Vitamin B 12; Vitamin B 12 Deficiency

A 19-year-old man presented with a 1-month history of progressive 4-limb numbness and gait imbalance. Physical examination revealed mild general muscular weakness, areflexia, and wide-based, ataxic, steppage gait. Sensory tests showed diminished superficial sensation below the level of the cervical-thoracic junction and a glove-and-stocking pattern of sensory loss at the 4 extremities. An initial magnetic resonance imaging examination of the cervical spine revealed an increased bilateral signal from the posterior and anterior columns on T(2)-weighted images. Nerve conduction velocity and electromyographic tests revealed polyneuropathy. On further inquiry, the patient admitted to chronic recreational use of nitrous oxide. The final diagnosis was nitrous oxide-induced neurotoxicity. The patient was treated for 5 days with injections of 1000 μg/day vitamin B(12), followed by an additional 2-month treatment at a dose of 1000 μg/week. The numbness resolved after the first week, but there remained a mild sensory ataxic gait. The patient recovered fully after 2 months of treatment and nitrous oxide abstinence. We recommend an investigation of the patient's history of nitrous oxide exposure in cases where an individual presents to the emergency department or outpatient department with acute numbness characterized by megaloblastic red blood cells and symmetric neurologic deficits.

Topics: Emergency Service, Hospital; Humans; Inhalant Abuse; Male; Nitrous Oxide; Polyneuropathies; Spinal Cord Diseases; Vitamin B 12; Vitamin B Complex; Young Adult

Chronic cough is characterized by sensory neuropathy. Vitamin B-12 (cobalamin) deficiency (Cbl-D) causes central and peripheral nervous system damage and has been implicated in sensory neuropathy and autonomic nervous system dysfunction.. We evaluated whether Cbl-D has a role in chronic, unexplained cough.. Laryngeal threshold (histamine concentration that provokes a 25% decrease in the midinspiratory flow), bronchial threshold (histamine concentration that provokes a 20% decrease in the forced expiratory volume in 1 s), and cough threshold (histamine concentration that causes ≥5 coughs) in response to an inhaled histamine were assessed in 42 patients with chronic, unexplained cough [27 Cbl-D patients and 15 patients without Cbl-D (Cbl-N)] before and after intramuscular injections of cobalamin for 2 mo. Laryngeal, bronchial, and cough hyperresponsiveness was diagnosed when histamine concentration thresholds were ≤8 mg/mL. Seven Clb-D and 3 Cbl-N patients underwent an oropharyngeal biopsy before treatment.. Cbl-D patients had a higher prevalence of laryngeal hyperresponsiveness than did Cbl-N patients (92.6% compared with 66.7%; P = 0.03), a thinner oropharyngeal epithelium [133.7 μm (95% CI: 95, 172 μm) compared with 230.8 μm (95% CI: 224, 237 μm); P = 0.002], a lower number of myelinated nerve fibers [2.25/mm(2) (95% CI: 1.8, 2.7/mm(2)) compared with 3.44/mm(2) (95% CI: 3, 3.8/mm(2)); P = 0.05], and a higher immunoreactive score for nerve growth factor (NGF) [6.7 (95% CI: 6, 7.3) compared with 2.8 (95% CI: 2.5, 3.1); P = 0.02]. After cobalamin supplementation, symptoms and laryngeal, bronchial, and cough thresholds were significantly improved in Cbl-D but not in Cbl-N patients.. This study suggests that Cbl-D may contribute to chronic cough by favoring sensory neuropathy as indicated by laryngeal hyperresponsiveness and increased NGF expression in pharyngeal biopsies of Cbl-D patients. Cbl-D should be considered among factors that sustain chronic cough, particularly when cough triggers cannot be identified.

Topics: Adult; Biopsy; Cough; Diagnosis, Differential; Female; Histamine; Humans; Immunohistochemistry; Lung; Male; Middle Aged; Mucous Membrane; Nerve Fibers, Myelinated; Nerve Growth Factor; Oropharynx; Polyneuropathies; Severity of Illness Index; Vitamin B 12; Vitamin B 12 Deficiency

Thirty-three inpatients (22 females, 11 males, aged 79.4 ± 9.5 years) were investigated in this prospective cohort study to study the prevalence of polyneuropathy (PNP) and dementia in geriatric inpatients. Clinical and electrodiagnostic investigations, routine laboratory, including thyroid parameters, folic acid, vitamin B(12), homocysteine, neopterin, fibrinogen and glycosylated hemoglobin were measured in serum, the mini-mental state examination and computed tomographic scanning were performed in each patient. PNP was found clinically and electrodiagnostically in 96% of patients. Age was the most precipitating factor for PNP, and was significantly correlated to electrodiagnostic changes in the nerves investigated in both, upper and lower extremities, while clinical symptoms were confined only to the feet. Correlation was seen between homocysteine and the amplitude of the sural nerve (surAmpl) (rs = -0.406, p = 0.029) as well as the sural nerve conduction velocity (surNCV) (rs = -0.389, p = 0.037), and between neopterin and the grade of denervation (rs = 0.445, p = 0.014) in our patients. Neopterin and fibrinogen did not correlate significantly, but there was a trend to higher fibrinogen concentrations in patients with higher neopterin levels (rs = 0.344, p = 0.062). A trend of a correlation was seen between higher homocysteine concentrations and the number of changes in electrodiagnostic measurements (rs = 0.354, p = 0.055). Twenty-one of the 33 patients (64%) were demented, 9 (27%) presented clinically as mild cognitive impairment, 3 (9%) were not demented. Vascular risk factors were found in 83%: hypertension in 58%, hypercholesterinemia in 39%, cardiac disease in 36%, diabetes mellitus (DM) in 21%, peripheral arterial disease (PAD) in 9%. A significant correlation was found between homocysteine and folic acid concentrations (rs = -0.401, p = 0.028). Falls were reported in 48% of cases, indicating PNP as a risk factor in this group of patients. In conclusion, PNP was found very common with a high coincidence with dementia and a female preponderance, suggesting an influence on daily life (falls) in our subjects studied. PNP correlated significantly with markers for vascular disease as well as immune activation (homocysteine and neopterin) similar to earlier findings in patients with neurodegenerative disorders, suggesting common therapeutic options in patients with PNP and dementia.

Topics: Aged; Aged, 80 and over; Aging; Cognition Disorders; Cohort Studies; Dementia; Female; Folic Acid; Geriatrics; Homocysteine; Humans; Inflammation; Male; Mental Status Schedule; Neopterin; Neural Conduction; Polyneuropathies; Sural Nerve; Vascular Diseases; Vitamin B 12

A 50-year-old man presented with a four-year history of unsteadiness, with recent falls and tingling in his fingers. Neurological examination found an ataxic gait, with a positive Romberg's sign. There was distal wasting and weakness in all four limbs and impaired co-ordination, with pseudoathetosis in the arms. Initial investigations showed a normochromic, normocytic anaemia, leucopenia, neutropenia and a low vitamin B(12) (172 ng/L). Treatment with intramuscular cobalamin injections showed no clinical improvement. Further investigations showed an undetectable caeruloplasmin (<0.085 g/L), a very low serum copper (1.1 μmol/L) and a markedly raised serum zinc concentration (36.2 μmol/L). On detailed questioning it became apparent that he had ill-fitting dentures requiring excessive use of denture fixative with high zinc content. The patient was switched to a non-zinc containing denture fixative and commenced copper supplementation. Although within three months the bone marrow suppression had resolved, there was no clinical improvement in neurological presentation. Questioning a patient about their denture fixative usage and checking if zinc is an ingredient may be considered during an investigation for myelopolyneuropathy when vitamin B(12) deficiency is not a cause.

Topics: Anemia; Ceruloplasmin; Copper; Dental Cements; Dentures; Diagnosis, Differential; Heavy Metal Poisoning; Humans; Male; Middle Aged; Neutropenia; Poisoning; Polyneuropathies; Vitamin B 12; Vitamin B 12 Deficiency; Zinc

Cobalamin (Cbl) deficiency affects the peripheral nervous system (PNS) morphologically and functionally. We investigated whether the octapeptide repeat (OR) region of prion protein (PrP(C)) (which is claimed to have myelinotrophic properties) is involved in the pathogenesis of rat Cbl-deficient (Cbl-D) polyneuropathy.. We intracerebroventricularly administered antibodies (Abs) against the OR region (OR-Abs) to Cbl-D rats to prevent myelin damage and maximum nerve conduction velocity (MNCV) abnormalities, and PrP(C)s to normal rats to reproduce PNS Cbl-D-like lesions. We measured nerve PrP(C) levels and MNCV.. The OR-Abs normalized myelin ultrastructure, MNCV values, and tumor necrosis factor (TNF)-α levels in the sciatic and tibial nerves of Cbl-D rats. PrP(C) levels increased in Cbl-D nerves. The nerves of the PrP(C)-treated rats showed typical Cbl-D lesions, significantly decreased MNCV values, and significantly increased TNF-α levels.. OR-Abs prevent the myelin damage caused by increased OR regions, and excess TNF-α is involved in the pathogenesis of Cbl-D polyneuropathy.

Topics: Animals; Mice; Neural Conduction; Oligopeptides; Polyneuropathies; PrPC Proteins; Rats; Rats, Sprague-Dawley; Tumor Necrosis Factor-alpha; Up-Regulation; Vitamin B 12

Topics: Anesthetics, Inhalation; Female; Humans; Illicit Drugs; Magnetic Resonance Imaging; Nitrous Oxide; Polyneuropathies; Spinal Cord; Vitamin B 12; Vitamins; Young Adult

Topics: 5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase; Anesthetics, Inhalation; Dentistry; Dentists; Humans; Nitrous Oxide; Occupational Diseases; Polyneuropathies; Receptors, Opioid; Substance-Related Disorders; Vitamin B 12

Topics: Aged; Anemia, Macrocytic; Comorbidity; Epilepsy; Humans; Male; Polyneuropathies; Vitamin B 12; Vitamin B Deficiency

Approximately 15% of people aged more than 60 years old have a cobalamin (vitamin B12) deficiency, mainly in relation with food-cobalamin malabsorption (FCM). To date, no study has documented this disorder in the elderly. There is also little information on clinical consequences.. We studied 92 elderly patients with well-established FCM who were extracted from an observational cohort study (1995-2004) of 172 consecutive elderly patients with documented cobalamin deficiency.. The median patient age was 76 +/- 8 years; 60 patients were women. The most common clinical manifestations were neurologic or psychologic: mild sensory polyneuropathy (44.6%), confusion or impaired mental functioning (22.8%), and physical asthenia (20.7%). Hematologic abnormalities were reported in at least one third of the patients: anemia (21%), leukopenia (10.9%), thrombopenia (8.7%), and pancytopenia (6.5%). All patients had low serum vitamin B12 levels (<200 pg/mL), with a mean value (+/- standard deviation) of 131 +/- 38 pg/mL and total serum homocysteine level of 22.1 +/- 9.3 micromol/L. The mean hemoglobin level was 10.9 +/- 2.5 g/dL and the mean erythrocyte cell volume 95.7 +/- 12.7 fL. Correction of the serum vitamin B12 levels and hematologic abnormalities was achieved equally well in patients treated with either intramuscular or oral crystalline cyanocobalamin.. This study suggests that in elderly patients, FCM may be associated with significant neurologic, psychologic, and hematologic abnormalities, which seem to respond equally well to either oral or parenteral vitamin B12 therapy.

Topics: Aged; Aged, 80 and over; Asthenia; Cognition Disorders; Cohort Studies; Confusion; Edema; Erythrocyte Indices; Female; Follow-Up Studies; Gastritis, Atrophic; Hematologic Diseases; Hemoglobins; Homocysteine; Humans; Jaundice; Malabsorption Syndromes; Male; Paresthesia; Polyneuropathies; Reflex, Abnormal; Retrospective Studies; Vitamin B 12; Vitamin B 12 Deficiency

A case of a 44-years-old patient with unusual clinical presentation of encephalomyelopolyneuropathy in vitamin B12 deficiency is presented. The disease manifested itself with gastrointestinal bleeding, which necessitated emergency hospitalisation in surgical clinic. Clinical examinations revealed atrophic gastritis, pernicious anemia, neurological and mental complications. The diagnosis was made according to the following criteria: physical examination--smooth tongue, atrophic gastritis, mild hepatosplenomegaly; laboratory findings--pernicious anemia, low vitamin B12 serum levels; neurological examination--syndrome of combined damage of the posterior and lateral columns of the spinal cord; magnetic resonance imaging--typical hyperintense areas on T2-weighted images in the posterior columns in the cervical regions of the spinal cord; transcranial magnetic stimulation--prolonged central motor conduction time of the motor evoked potentials bilaterally; psychological examination--cognitive decline. After treatment with vitamin B12 an improvement of the hematological findings, neurological deficit and cognitive impairments was found.. Neurological complications could be an early manifestation of vitamin B12 deficiency. In diagnostic aspect similar complaints require examination of the serum levels of vitamin B12. The delay in diagnosis and inadequate therapy bear the risk of incomplete recovery of the neurological deficit. The current problem of "cognitive decline" necessitates routine examination of the serum levels of vitamin Bl2 in all patients with initial cognitive impairments and their prompt and approapriate treatment.

Topics: Adult; Central Nervous System Diseases; Cognition Disorders; Humans; Male; Polyneuropathies; Vitamin B 12; Vitamin B 12 Deficiency

Polyneuropathy is one of the most frequent manifestations in chronic uremia. Among the factors related to polyneuropathy, vitamin B6 deficiency is well known. The exact prevalence of vitamin B6 deficiency related to neurological manifestations has not been previously reported. We studied vitamin B6 status, collected self-reported symptoms, and carried out full neurological examinations in 66 patients on chronic peritoneal dialysis. Vitamin B6 status was estimated by direct measurement of pyridoxal phosphate. In general, symptoms related to vitamin B6 deficiency are peripheral neuropathies, such as paresthesia, burning and painful dysesthesias, and thermal sensations. These symptoms were reported and assigned one of five grade scores. Of our 66 patients, 12 patients complained at least one sensory abnormality. The levels of vitamin B6 in the patients varied between 1.0 ng/mL and 30 ng/mL. Patients who complained of neurological symptoms owing to vitamin B6 deficiency were significantly older than the other patients. In analyzing the symptomatic cases before and after vitamin B6 supplementation, a significant correlation was seen between the level of vitamin B6 and symptoms. Within one month after initiation of oral vitamin B6 supplementations (30 mg daily), levels of pyridoxal phosphate rose, and sensory abnormalities improved in 8 of 12 patients. When peripheral neuropathy is suspected in elderly patients on chronic peritoneal dialysis, vitamin B6 deficiency should be taken into consideration as the cause. If vitamin B6 deficiency is appropriately treated by oral supplementation, sensory abnormalities can be eliminated.

Topics: Adolescent; Adult; Age Factors; Aged; Female; Humans; Male; Middle Aged; Paresthesia; Peritoneal Dialysis; Polyneuropathies; Pyridoxal Phosphate; Pyridoxine; Vitamin B 12; Vitamin B 6 Deficiency

Vitamin B12 deficiency is an uncommon disorder in a prosperous western country. In two children a nutritional vitamin B12 deficiency was observed. The first was a 2-year-old girl with neurodevelopmental regression and macrocytic anaemia, a result of a combination of a maternal vitamin B12 deficiency and inadequate feeding after birth. The second patient was a 14-year-old adipose girl with severe polyneuropathy and mild macrocytic anaemia as a result of a nutritional vitamin B12 deficiency. In her case the deficiency resulted from a bizarre feeding pattern. She turned out to be the victim of child abuse. It is concluded that even in a prosperous western country like the Netherlands vitamin B12 deficiency in children can develop as a result of an inadequate feeding pattern. It can lead not only to macrocytic anaemia but also to severe neurological abnormalities.

Topics: Adolescent; Child Abuse; Child, Preschool; Diagnosis, Differential; Diet; Feeding Behavior; Female; Humans; Polyneuropathies; Polyradiculoneuropathy; Vitamin B 12; Vitamin B 12 Deficiency

Topics: Aged; Humans; Male; Polyneuropathies; Sciatica; Vitamin B 12

Topics: Abortion, Spontaneous; Air Pollutants; Anesthetics; Animals; Female; Gases; Humans; Nitrous Oxide; Operating Rooms; Oxidation-Reduction; Polyneuropathies; Pregnancy; Rats; Vitamin B 12

Topics: Adult; Aged; Diabetic Neuropathies; Humans; Methionine; Middle Aged; Nervous System Diseases; Neuritis; Peripheral Nervous System Diseases; Physical Therapy Modalities; Polyneuropathies; Thioctic Acid; Transketolase; Vitamin B 12

Topics: Adult; Alcoholism; Folic Acid; Humans; Hypesthesia; Muscle Cramp; Neural Conduction; Polyneuropathies; Reflex, Abnormal; Sensation; Thiamine; Vitamin B 12

Thirty-eight patients with vitamin B12 deficiency after gastric surgery for a benign peptic ulcer were examined electrophysiologically. Thirteen (34 per cent) had electromyographical signs of peripheral nerve involvement and the amplitude of the sensory potentials of the median nerve at wrist (16 patients) was diminished, whereas sensory and motor conduction velocities were normal. Six patients had clinical signs of polyneuropathy. The electrophysiological findings are compatible with slight loss of myelinated nerve fibres. None of the patients had clinical or electromyographical signs of myopathy.

Topics: Action Potentials; Female; Humans; Male; Middle Aged; Neural Conduction; Peripheral Nerves; Polyneuropathies; Postgastrectomy Syndromes; Vitamin B 12; Vitamin B 12 Deficiency

Topics: Acrylates; Adult; Anemia; Asthenia; Calcium; Chemical Phenomena; Chemistry, Physical; Creatinine; Female; Filtration; Humans; Kidneys, Artificial; Male; Membranes, Artificial; Middle Aged; Molecular Weight; Nitriles; Peritoneal Dialysis; Permeability; Polyneuropathies; Renal Dialysis; Succinates; Time Factors; Urea; Uremia; Uric Acid; Vitamin B 12

Topics: Adult; Aged; Anorexia Nervosa; Cobamides; Coenzymes; Drug Combinations; Evaluation Studies as Topic; Feeding and Eating Disorders; Female; Humans; Liver Diseases; Male; Middle Aged; Polyneuropathies; Pyridoxal Phosphate; Thiamine; Thiamine Pyrophosphate; Vitamin B 12

Topics: Adult; Aged; Alcoholism; Humans; Male; Middle Aged; Neuralgia; Paralysis; Paresthesia; Polyneuropathies; Polyradiculopathy; Vitamin B 12

Topics: Adult; Female; Humans; Hydrazines; Injections, Intramuscular; Isoniazid; Isonicotinic Acids; Male; Middle Aged; Polyneuropathies; Riboflavin; Thiamine; Vitamin B 12

Topics: Betamethasone; Brachial Plexus Neuritis; Humans; Intervertebral Disc Displacement; Joint Diseases; Neuralgia; Polyneuropathies; Polyradiculopathy; Sciatica; Spinal Diseases; Vitamin B 12

Topics: Adenine Nucleotides; Aminopyrine; Animals; Drug Synergism; Male; Polyneuropathies; Rats; Suppositories; Vitamin B 12; Vitamin B Complex

Topics: Folic Acid; Humans; Malabsorption Syndromes; Polyneuropathies; Riboflavin; Vitamin A; Vitamin B 12; Vitamin B Complex; Vitamin D; Vitamin K

Topics: Bromides; Folic Acid; Humans; Hydrocarbons, Brominated; Neurology; Physical Therapy Modalities; Polyneuropathies; Thiamine; Toxicology; Vitamin B 12; Vitamin B Complex

Topics: Adipose Tissue; Anemia; Anemia, Pernicious; Hematinics; Humans; Neuritis; Polyneuropathies; Vitamin B 12

Topics: Hematinics; Humans; Neuritis; Polyneuropathies; Vitamin B 12; Vitamin B Complex