Vitamin B12 deficiency in dialysis patients:risk factors,diagnosis,complications,and treatment:A comprehensive review

Vitamin B12 deficiency is a significant concern among patients with end-stage renal disease undergoing dialysis.However,there hasn’t been extensive research conducted on this particular patient group.The reported incidence rates vary widely,ranging from 20%to 90%,reflecting the complexity of its diagnosis.Dialysis patients often face multiple nutritional deficiencies,including a lack of essential vitamins,due to factors such as dietary restrictions,impaired absorption,and nutrient loss during dialysis.Diagnosing vitamin B12 deficiency in these patients is challenging,and addressing it is crucial to prevent complications and improve their overall quality of life.This review paper delves into the available body of evidence on vitamin B12 deficiency in dialysis patients,examining the contributing risk factors,diagnostic challenges,potential complications,and available treatment options.It provides a well-rounded perspective on the topic,making it a valuable resource for researchers,healthcare practitioners,and policymakers interested in addressing the nutritional needs of dialysis patients.

Neurological Manifestations of Vitamin B12 Deficiency: About a Case

The authors report a case of deficient sensory neuropathy secondary to vitamin B12 deficiency, diagnosed in the neurology department of the Sino-Central African Friendship University Hospital in Bangui. The diagnosis was made possible by electroneuromyography which showed subclinical neurological damage associated with hematological damage (anemia). Through this observation, we recall the diagnostic criteria of the disease in a context of difficult medical practice. .

Association between metformin and vitamin B12 deficiency in patients with type 2 diabetes

Diabetes mellitus(DM)is still one of the most common diseases worldwide,and its prevalence is still increasing globally.According to the American and European recommendations,metformin is considered a first-line oral hypoglycemic drug for controlling type 2 DM(T2DM)patients.Metformin is the ninth most often prescribed drug in the world,and at least 120 million diabetic people are estimated to receive the drug.In the last 20 years,there has been increasing evidence of vitamin B12 deficiency among metformin-treated diabetic patients.Many studies have reported that vitamin B12 deficiency is related to the malabsorption of vitamin B12 among metformin-treated T2DM patients.Vitamin B12 deficiency may have a very bad complication for the T2DM patient.In this review,we will focus on the effect of metformin on the absorption of vitamin B12 and on its proposed mechanisms in hindering vitamin B12 absorption.In addition,the review will describe the clinical outcomes of vitamin B12 deficiency in metformintreated T2DM.

Role of vitamin B12 deficiency in ischemic stroke risk and outcome

Currently,ischemic stroke is the most prevalent form of stroke compared to hemorrhagic and there is a high incidence in older adults.Nutrition is a modifiable risk factor for stroke.B-vitamins are part of a metabolic network that integrates nutritional signals with biosynthesis,redox homeostasis,and epigenetics.These vitamins play an essential role in the regulation of cell proliferation,stress resistance,and embryo development.A deficiency in vitamin B12 is common in older adults and has been reported to be implicated in ischemic stroke.The aim of this review was to investigate whether vitamin B12 deficiencies impact the risk and outcome of ischemic stroke.Clinical data from our literature review strongly suggest that a deficiency in vitamin B12 is a risk factor for ischemic stroke and possible outcome.Our survey of the literature has identified that there is a gap in the understanding of the mechanisms through which a vitamin B12 deficiency leads to an increased risk of stroke and outcome.A vitamin B12 deficiency can increase homocysteine levels,which are a well-established risk factor for ischemic stroke.Another potential mechanism through which vitamin B12 deficient may impact neurological function and increase risk of stroke,is changes in myelination,however this link requires further investigation.Further studies are required in model systems to understand how a vitamin B12 deficiency changes the brain.

Vitamin B complex and vitamin B12 levels after peripheral nerve injury

The aim of the present study was to evaluate whether tissue levels of vitamin B complex and vitamin B12 were altered after crush-induced peripheral nerve injury in an experimental rat model. A total of 80 male Wistar rats were randomized into one control（n = 8） and six study groups（1, 6, 12, 24 hours, 3, and 7 days after experimental nerve injury; n = 12 for each group）. Crush-induced peripheral nerve injury was performed on the sciatic nerves of rats in six study groups. Tissue samples from the sites of peripheral nerve injury were obtained at 1, 6, 12, 24 hours, 3 and 7 days after experimental nerve injury. Enzyme-linked immunosorbent assay results showed that tissue levels of vitamin B complex and vitamin B12 in the injured sciatic nerve were significantly greater at 1 and 12 hours after experimental nerve injury, while they were significantly lower at 7 days than in control group. Tissue level of vitamin B_（12） in the injured sciatic nerve was significantly lower at 1, 6, 12 and 24 hours than in the control group. These results suggest that tissue levels of vitamin B complex and vitamin B12 vary with progression of crush-induced peripheral nerve injury, and supplementation of these vitamins in the acute period may be beneficial for acceleration of nerve regeneration.

Long-term metformin therapy and vitamin B12 deficiency: An association to bear in mind

To date,metformin remains the first-line oral glucose-lowering drug used for the treatment of type 2 diabetes thanks to its well-established long-term safety and efficacy profile.Indeed,metformin is the most widely used oral insulinsensitizing agent,being prescribed to more than 100 million people worldwide,including patients with prediabetes,insulin resistance,and polycystic ovary syndrome.However,over the last decades several observational studies and meta-analyses have reported a significant association between long-term metformin therapy and an increased prevalence of vitamin B12 deficiency.Of note,evidence suggests that long-term and high-dose metformin therapy impairs vitamin B12 status.Vitamin B12(also referred to as cobalamin)is a water-soluble vitamin that is mainly obtained from animal-sourced foods.At the cellular level,vitamin B12 acts as a cofactor for enzymes that play a critical role in DNA synthesis and neuroprotection.Thus,vitamin B12 deficiency can lead to a number of clinical consequences that include hematologic abnormalities(e.g.,megaloblastic anemia and formation of hypersegmented neutrophils),progressive axonal demyelination and peripheral neuropathy.Nevertheless,no definite guidelines are currently available for vitamin B12 deficiency screening in patients on metformin therapy,and vitamin B12 deficiency remains frequently unrecognized in such individuals.Therefore,in this“field of vision”article we propose a list of criteria for a cost-effective vitamin B12 deficiency screening in metformin-treated patients,which could serve as a practical guide for identifying individuals at high risk for this condition.Moreover,we discuss additional relevant topics related to this field,including:(1)The lack of consensus about the exact definition of vitamin B12 deficiency;(2)The definition of reliable biomarkers of vitamin B12 status;(3)Causes of vitamin B12 deficiency other than metformin therapy that should be identified promptly in metformin-treated patients for a proper differential diagnosis;and(4)Potential pathophysiological mechanisms underlying metformin-induced vitamin B12 deficiency.Finally,we briefly review basic concepts related to vitamin B12 supplementation for the treatment of vitamin B12 deficiency,particularly when this condition is induced by metformin.

Folate and vitamin B12 in idiopathic male infertility

Although methylenetetrahydrofolate reductase, a folate enzyme gene, has been associated with idiopathic male infertility, few studies have examined other folate-related metabolites and genes. We investigated whether idiopathic male infertility is associated with variants in folate, vitamin B12 （B12） and total homocysteine （tHcy）-related genes and measured these metabolites in blood. We conducted a case-control study that included 153 men with idiopathic infertility and 184 fertile male controls recruited at the Fertility Center and Antenatal Care Center, University Hospital, Malmo and Lund, Sweden. Serum folate, red cell folate （RCF）, serum B12, plasma tHcy and semen quality were measured. Subjects were genotyped for 20 common variants in 12 genes related to folate/B12/ homocysteine metabolism. Metabolite concentrations and genotype distributions were compared between cases and controls using linear and logistic regression with adjustment for covariates. The phosphatidylethanolamine N-methyltransferase （PEMT） M 175V and TCblR rs173665 polymorphisms were significantly associated with infertility （P=0.01 and P=0.009, respectively）, but not with semen quality. Among non-users of supplements, infertile men had lower serum folate concentrations than fertile men （12.89 vs. 14.73 nmoll^- 1 P=0.02）, but there were no significant differences in RCF, B 12 or tHcy. Folate, B 12 and tHcy concentrations were not correlated with any semen parameters. This study provides little support for low folate or B12 status in the pathogenesis of idiopathic male infertility. Although additional data are needed to confirm these initial findings, our results suggest that PEMTand TCbIR, genes involved in choline and B12 metabolism, merit further investigation in idiopathic male infertility.

Vitamin B12 deficiency and gastric histopathology in older patients

AIM: To compare upper gastric endoscopic and histopathologic findings in older adults in the presence and absence of B12 deficiency.METHODS: A prospective analysis of upper gastric endoscopic and gastric histopathologic findings from 30 newly identified B12-deficient patients (11 males,19 females) and 16 controls with normal B12 status (6males, 10 females) was performed. For all subjects, the indication for upper endoscopy and gastric biopsy were unrelated to B12 status. A single pathologist, blinded to B12 status, processed and interpreted the biopsy samples. Endoscopic and histopathologic findings were correlated with age, gender, hematocrit (Hct), MCV and B12 status.RESULTS: The B12-deficient group had significantly lower mean serum B12 levels compared to the controls (P＜0.00005) while their mean Hct, MCV and serum albumin levels were similar. Iron deficiency (ferritinbased) was present in 21% of B12-deficient patients and intrinsic factor antibodies were present in29% (5/17) of B12-deficient patients. The endoscopic findings revealed significantly different rates of gastritis and atrophy between the B12-deficient and control groups (P= 0.017).B12-deficient patients had significantly less superficial gastritis (62% vs 94%) and significantly more atrophic gastritis (28% vs 0%) as compared to the controls (P= 0.039). Intestinal metaplasia was similar in both groups. Helicobacter pyloriinfection rates were similar in the B12-deficient patients and controls (40% vs31%).CONCLUSION: Significantly different endoscopic findings and types of gastritis could often be observed in the presence and absence of B12 deficiency. Atrophy,based on endoscopy, and atrophic gastritis, based on histopathology, suggest the presence of B12 deficiency.Gastric histopathology is not influenced by the age,gender, Hct or MCV of the patients.

Effect of vitamin B12 deficiency anemia on peripapillary retinal nerve fiber layer

AIM:To evaluate the effect of vitamin B12 deficiency anemia(BDA)on peripapillary retinal nerve fiber layer thickness(RNFLT)using spectral domain optical coherence tomography(SD-OCT),and to determine any correlation arising thereof.METHODS:In this cross-sectional observational study,99 eyes of 50 BDA patients of age 18-65 y were compared with 100 eyes of 50 healthy control subjects.All subjects underwent comprehensive clinical,ophthalmic,and hematological evaluation,followed by peripapillary RNFLT assessment using SD-OCT.RESULTS:The mean total,inferior,nasal,and temporal RNFLT were significantly lower in BDA group as compared to control group(P<0.05).The mean total,inferior and nasal RNFLT correlated significantly(P<0.05)with serum Hb%,B12 and mean corpuscular volume(MCV)level(r=0.310,0.435,-0.386 for total;r=0.932,0.481,-0.513 for inferior;r=0.344,0.254,-0.233 for nasal;respectively),while temporal and superior RNFLT quadrant did not show any correlation with any of the hematological parameters(r=0.144,0.167,-0.096;r=0.111,0.070,-0.099;respectively).The mean total RNFLT showed progressive thinning at par with the progression of anemia,except in very severe BDA,where an inverse relationship was documented.CONCLUSION:The mean total,inferior,nasal,and temporal peripapillary RNFLT was significantly thinner in BDA patients.Peripapillary RNFLT thinning seemed to proceed at par with the progression of severity of anemia,except in very sever grade.Early assessment of peripapillary RNFLT may be crucial in BDA patients to prevent potential blinding sequelae.Peripapillary RNFLT thinning in BDA patients should be considered in the differential diagnosis of other non-glaucomatous optic neuropathies,as well.

Determination of Vitamin B12 Using Differential Pulse Polarography

Vitamin B12 is a type of vitamin also known by the name cobalamin. B12 is involved in many metabolism activities, including DNA synthesis, nervous system, red blood formation and immune system. Therefore, we chose the Differential Pulse Polarography (DPP) method is that has a high sensitivity for the determination of vitamin B12. This determination was possible with cobalt present in vitamin B12 structure. Since Co(III) is formed from the oxidation of the vitamin, its polarographic behavior had to be determined in various electrolytes such as acetate, borate, phosphate and ammonia. The polarograms of Co(III) were taken in these electrolytes in which 1.0 M NH3/ (pH = 9.8) and 1.0 M AcOH/AcO- (pH = 4.0) were found as the most suitable electrolytes. This method was successfully applied vitamin of B12 determination in a 1 mL ampoule with high precision. The LOD was found as 3.7 × 10-7 for instead of (S/N = 3). Besides Co(III), interference effects of Zn(II), Ni(II), Cr(III), Fe(III), Cu(II), Cd(II) and Se(IV) were also studied. It was found that only Zn(II) peak had an overlap Co(III) peak in ammonium buffer. This problem could be solved by working in 1.0 M AcOH/AcO- (pH = 4.0) buffer. B12, which is 1000 μg in 1 mL vitamin ampoule, was found for 4 measurements as 999 ± 15 μg as a result of 95% confidence interval.

Hcy相关酶基因MS A2756G、MTRR A66G多态性及Vitamin B12与脑梗死相关性的临床探讨

目的探讨同型半胱氨酸(Hcy)相关酶基因甲硫氨酸合成酶(methioninesynthase,MS)基因A2756G和甲硫氨酸合成酶还原酶(MTRR)基因A66G多态性对维生素B12和Hcy代谢的影响以及与脑梗死的关系,为寻找脑血管病易感基因提供理论依据。方法选取2014年2月-2016年2月在中日友好医院神经内科确诊为急性脑梗死患者100例作为病例组,选取同期的健康体检者100例为对照组,检测血浆Hcy水平和维生素B12的水平,聚合酶链反应-限制片段长度多态性(PCR-RFLP)技术分析基因型的多态性。在维生素B12干预试验中,100例急性脑梗死患者随机分为两组,每组50例,在常规治疗的基础上,试验组予以每天摄入0.5～1 mg维生素B12,而非试验组不服用,1 w后,检测患者血浆中Hcy指标。结果病例组血浆中Hcy的水平明显高于对照组;MS 2756AG、2756GG、MTRR 66AG、66GG型研究对象血浆中Hcy水平明显高于MS 2756AA、MTRR 66AA型研究对象;两组研究对象MS A2756G和MTRR A66G的基因型频率分布有显著性差异;病例组血浆中维生素B12的水平明显低于对照组,血浆中维生素B12的水平与Hcy的水平呈显著负相关;腺苷钴胺干预可明显降低脑梗死患者血浆中的Hcy水平。结论 MS基因A2756G突变和MTRR基因A66G突变是血浆中Hcy升高的重要因素,与脑梗死密切相关,可作为诊断和治疗的分子靶标;腺苷钴胺干预治疗可降低脑梗死患者血浆中Hcy水平。

Correlation between serum vitamin B12 level and peripheral neuropathy in atrophic gastritis

AIM To explore the correlation between serum vitamin B12 level and peripheral neuropathy in patients with chronic atrophic gastritis(CAG). METHODS A total of 593 patients diagnosed with chronic gastritis by gastroscopy and pathological examination fromSeptember 2013 to September 2016 were selected for this study. The age of these patients ranged within 18-to 75-years-old. Blood pressure, height and weight were measured in each patient, and the body mass index value was calculated. Furthermore, gastric acid, serum gastrin, serum vitamin and serum creatinine tests were performed, and peripheral nerve conduction velocity and Helicobacter pylori(H. pylori) were detected. In addition, the type of gastritis was determined by gastroscopy. The above factors were used as independent variables to analyze chronic gastritis with peripheral neuropathy and vitamin B12 deficiency risk factors, and to analyze the relationship between vitamin B12 levels and peripheral nerve conduction velocity. In addition, in the treatment of CAG on the basis of vitamin B12, patients with peripheral neuropathy were observed. RESULTS Age, H. pylori infection, CAG, vitamin B9 and vitamin B12 were risk factors for the occurrence of peripheral nerve degeneration.Furthermore,CAG and H. pylori infection were risk factors for chronic gastritis associated with vitamin B12 deficiency. Serum vitamin B12 level was positively correlated with sensory nerve conduction velocity in the tibial nerve(R = 0.463). After vitamin B12 supplementation, patients with peripheral neuropathy improved. CONCLUSION Serum vitamin B12 levels in patients with chronic gastritis significantly decreased, and the occurrence of peripheral neuropathy had a certain correlation. CAG and H. pylori infection are risk factors for vitamin B12 deficiency and peripheral neuropathy. When treating CAG, vitamin B12 supplementation can significantly reduce peripheral nervous system lesions. Therefore, the occurrence of peripheral neuropathy associated with vitamin B12 deficiency may be considered in patients with CAG. Furthermore, the timely supplementation of vitamin B12 during the clinical treatment of CAG can reduce or prevent peripheral nervous system lesions.

The Impact of Third Trimester Maternal Serum Vitamin B12 and Folate Status on Fetal Birth Weight. Is Maternal Serum Homocysteine a Predictor of Low Birth Weight Infants?

Objective: The aim of this study is to evaluate vitamin B12, folate, and homocysteine status in pregnant women in the third trimester of pregnancy and their relationship to fetal birth weight and their correlation to corresponding neonatal cord blood levels, and in addition, to evaluate the possibility of maternal serum homocysteine level as a predictor of low birth weight infants. Subjects and Methods: In this cross-sectional study, a total of two hundred pregnant women in third trimester (≥28 weeks) were recruited. After a detailed obstetrical and medical history, and clinical assessment, participants were subdivided into two groups: Group (A)—pregnant women who delivered average birth weight (ABW) infants and Group (B) for those who delivered low birth weight (LBW) infants between completed 37 and 42 weeks. Results: Vitamin B12 deficiency was observed in 24.1% of the total cohort. The mean vitamin B12 level was significantly lower in group (B) compared to group (A) (195.2 ± 38.9 vs. 225.9 ± 66.59 respectively P = 0.008). The mean level of homocysteine for women in group (B) was significantly higher than those determined from women in group (A) (9.10 ± 5.9 vs. 7.6 ± 3.83 respectively, P = 0.042). On the other hand, the mean folate levels showed statistically insignificant differences between both groups. The mean cord vitamin B12 level was significantly lower in LBW infants in comparison to ABW infants (277 ± 61.93 vs. 312.03 ± 81.87 respectively, P = 0.015), while the mean level of cord homocysteine for LBW infants was significantly higher than those levels determined from ABW infants (7.9 ± 3.79 vs. 6.6 ± 2.09 respectively P = 0.0049). Conclusion: Maternal micronutrients particularly cobalamin deficiency could be significant risk for LBW infants. Hyperhomocysteinemia has been shown to be a predictor for adverse pregnancy outcomes particularly LBW.

Methylmalonic acid as an indicator of vitamin B12 deficiency in patients on metformin

Context: Metformin is frequently prescribed for the treatment of type 2 diabetes mellitus. It is recommended as a first line agent by the American Diabetes Association. Vitamin B12 deficiency has been suggested as a side effect of metformin therapy;however, previous studies have not assessed the utility of methylmalonic acid levels as an indicator of vitamin B12 status. Objective: To investigate the prevalence of vitamin B12 deficiency in patients on metformin therapy for diabetes by utilizing both vitamin B12 and methylmalonic acid levels. Design, Setting, and Patients: Eighty-eight patients with diabetes, who were either on or off metformin therapy for at least thirty days, were enrolled in a case-controlled study. Blood work and questionnaires were used for analysis. Main Outcome Measures Study: Aims were to detect a clinically significant difference in the prevalence of vitamin B12 deficiency between metformin users and non-users, where such deficiency is defined by both low vitamin B12 and elevated methylmalonic acid levels. Results: Two Sample Equal Variance T-Tests were used to compare averages of measured values and the Chisquare test was used to determine the significance of calculated vitamin B12 deficiency rates between the two groups of patients. Two separate methods for defining vitamin B12 deficiency were utilized. There was no difference in the prevalence of vitamin B12 deficiency in metformin users compared with non-users by either method. Average homocysteine levels were higher in those not on metformin therapy. Conclusion: Vitamin B12 deficiency as defined by an elevated methylmalonic acid level was no greater in patients with diabetes on metformin therapy versus those patients not on metformin treatment.

Vitamin B12 Screening in Cervical Spine Surgery Patients

Introduction Vitamin B12 is very vital for the nervous system. Its deficiency can manifest with neurological symptoms like pain and paresthesias and in severe cases may cause not completely restorable neurological damage, especially in elderly patients. Methods The charts of 702 patients who underwent cervical spine surgery retrospectively reviewed and data collected . All patients were preoperatively seen by an internist who ordered Vit B12 levels for some of them. We used two thresholds for the diagnosis of vitamin B12 deficiency, 200 and 300 pg/mL as recommended by Yao et al. 1992. Data were also collected on gender, payor status, myelopathy, hemoglobin level, corpuscular parameters and glycosylated hemoglobin level (HbA1c). Vitamin B12 levels were compared between patients with HbA1c levels ≥ 6.1% and <6.1%. Differences between patients ≥ and < than the median age were studied. The median age of the patient cohort was 52. Results Hemoglobin level was recorded for 659 patients. Vit B12 levels were ordered for 291 patients only. Overall, 13.7% had decreased hemoglobin level (anemia), 30.2% had decreased Vit B12 levels by the 300 threshold, 6.9% had decreased Vit B12 levels by the 200 threshold, 6.3% decreased MCV (microcytosis), and 2.8% increased MCV (macrocytosis). Only four patients (0.7%), of whom older than 52, had decreased hemoglobin level and increased MCV (macrocytic anemia) and one patient (0.4%), who was also older than 52, had decreased hemoglobin level, increased MCV and Vit B12 level < 200 pg/mL (macrocytic anemia duo to Vit B12 deficiency). Dividing the patient sample into three age groups, <40, 40-59, and ≥ 60 years, we investigated the trend of cobalamin deficiency by age and found an increase in cobalamin deficiency after 40 from 0% to 7.4% (200 threshold). Uninsured patients (25%) using the 200 pg/mL threshold and workers’ compensation (54.5%) and uninsured patients (50.0%) had the highest rate of Vit B12 deficiency using the 300 pg/mL threshold. The few patients with macrocytic anemia (N=4) and macrocytic anemia due to Vit B12 deficiency (N=1) had health coverage. Conclusion Vit B12 deficiency in cervical spine surgery patients may not necessarily mean macrocytic anemia but may precede macrocytic anemia. Therefore, Vit B12 deficiency screening on the preoperative visit is warranted especially in uninsured or older patients or both. Preoperative treatment may be indicated and correlation with postoperative outcome is suggested for future research.

Vitamin B12 in pregnancy: Maternal and fetal/neonatal effects—A review

Vitamin B12 maintains normal folate metabolism which is essential for cell multiplication during pregnancy. No good data are available on what constitutes vitamin B12 deficiency in pregnancy, nevertheless vitamin B12 deficiency is frequently reported in pregnancy due to inadequate dietary intake of vitamin B12 and a physiological decline of maternal vitamin B12 concentrations. This decline can be explained by the increased maternal metabolic rate and active transport by the placenta to the fetus. If the mother is deficient during pregnancy, the baby may have low serum vitamin B12 concentrations at birth [1]. Vitamin B12 deficiency during pregnancy is associated with preeclampsia, fetal growth restriction, preterm labor, neural tube defects, neonatal megaloblastic anemia and neonatal neurological symptoms. It has been suggested to improve vitamin B12 status of women in the periconceptional period by supplementation of vitamin B12, but no randomized studies on the outcome of such supplementation have been published.

Determining the efficacy of vitamin B12 mixed oral liquid in the treatment of radiation-induced esophagitis

Objective This study aimed to investigate the effects of vitamin B12 mixed oral liquid in the treatment of radiation-induced esophagitis in patients with esophageal cancer.Methods Seventy-five patients with esophageal cancer who met the enrollment criteria were randomly divided into the vitamin B12 mixed oral liquid group(39 patients in the study group)and the gentamicin mixed oral liquid group(36 patients in the control group).The effects of the two treatment methods on esophagitis grading,pain degree,body weight loss,and Karnofsky performance status(KPS)score in patients with radiation esophagitis were observed.Results In the control group,grade 1 radiation esophagitis accounted for 27.8%of the total patients,grade 2 accounted for 41.7%,and grades 3 and 4 accounted for 30.6%.In the vitamin B12 treatment group,grade 1 radiation esophagitis accounted for 66.7%of the total patients,grade 2 accounted for 25.6%,and grades 3 and 4 accounted for 7.7%;there was a significant difference between the vitamin B12 treatment group and control group(P<0.01).Similarly,pain caused by radiation esophagitis was significantly improved in the vitamin B12 group compared with the control group(P<0.05).After treatment,the average weight loss of the control group was(2.18±0.36)kg,while that of the vitamin B12 treatment group was(0.90±0.43)kg(P<0.05).The KPS scores of the vitamin B12 group were higher than those of the control group,which were 86.2±1.2 and 85.6±1.5,respectively,but there was no statistical difference(P>0.05).Conclusion Vitamin B12 mixed oral liquid can effectively reduce the severity of radiation esophagitis,relieve pain,improve patients’quality of life,and increase treatment compliance.

Status of Vitamin B12 Deficiency in the Elderly Chinese Community People

This study was aimed to investigate the vitamin B12 deficiency prevalence and symptoms in elderly people lived in a community of Shanghai, China. A total number of 962 elderly people resided in Shanghai community were recruited in the present study. They were 60 years and older, and the average age was 76.38 ± 13.68 years old. Information on previous and present diseases, currently prescribed and over-the-counter medication, and the presence or absence of symptoms relating to vitamin B12 deficiency were obtained by questionnaire. The levels of serum vitamin B12, folate and homocysteine (Hcy) were estimated. The patients with vitamin B12 deficiency were screened. The results of symptoms and positive signs of neurological examination were compared between subjects with or without vitamin B12 deficiency. The results showed that vitamin B12 deficiency was found in 130 persons (13.53% of the total subjects), with an increase in incidence with aging, only 10% of the vitamin B12 deficient subjects had megaloblastic anemia. The reported symptoms of vitamin B12 deficient subjects included fatigue, memory decline, dizziness, unsteadily walking in the darkness and hypopallesthesia. In conclusion, vitamin B12 deficiency was remarkably common in Chinese elderly people, with various and atypical clinical manifestations, and the neurological symptoms were more common than those of megaloblastic anemia.

Serum Vitamin B12 and Homocysteine Levels in Type 2 Diabetic Patients with and without Metformin Therapy

Background: Vitamin B12 (cobalamin) is an essential micronutrient necessary for DNA methylation and plays role in lipid metabolic reactions. Metformin is the first therapeutic choice for T2DM management. Prolonged use of metformin causes vitamin B12 deficiency due to poor absorption by interfering with calcium-based vitamin B12 absorption. Vitamin B12 deficiency leads to elevated homocysteine levels. The aim of this study was to evaluate serum vitamin B12 and homocysteine levels in type 2 diabetic patients with and without metformin therapy. Methods: A cross-sectional study was conducted on two hundred and thirty diabetic patients (180 males and 50 females). Their ages ranged from (30 - 60 years) living in Saudia Arabia at Al-Madinah Al-Monawarah. Patients were selected at outpatients clinics of Islamic University Medical Center during follow up at internal medicine and endocrinology clinic. The included patients were diagnosed with type 2 diabetes mellitus according to American Diabetes Association (ADA) Criteria. The included patients were categorized into two groups according to treatment with metformin drug. Laboratory measurements included serum level of vitamin B12, serum total homocysteine, serum fasting glucose and serum folate. Blood EDTA samples were used to measure HbA1c and MCV. Neurological examinations were performed to detect presence of peripheral neuropathy using Toronto Clinical Neuropathy Score (TCSS), which is a validated and reliable scale for the diagnosis and staging of diabetic polyneuropathy. Results: There were no statistical differences between the two groups as regard (age, sex, smoking, weight, BMI, systolic blood pressure, diastolic blood pressure, fasting blood glucose, Folate and MCV). There were statistical differences between the two groups as regard (duration of diabetes, duration of metformin therapy, dose of metformin, Serum homocystein and HbA1c). The mean of vitamin B12 (pg/mL) of group 1 (312.65 ± 92.28) was lower than that of group 2 (381.55 ± 88.04). In group 1 number of patients with normal vitamin B12 was 116 out of 150 (77.3%) and number of patients with deficient vitamin B12 was 34 out of 150 (22.7%). In group 2 number of patients with normal vitamin B12 was 72 out of 80 (90%) and number of patients with deficient vitamin B12 was 8 out of 80 (10%). Regarding neuropathy;in group 1 113 patients (75.3%) had no neuropathy, 24 patients (16%) had mild neuropathy and 13 patients (8.7%) had moderate neuropathy. In group 2, 71 patients (88.8%) had no neuropathy, 7 patients (8.7%) had mild neuropathy and 2 patients (2.5%) had moderate neuropathy. In conclusion, in our study, the prevalence of vitamin B12 deficiency was higher in metformin users than in non-metformin users. There was an association between vitamin B12 deficiency and the dose and duration of metformin use. There was also an increase in homocysteine level due to vitamin B12 deficiency. Therefore, we recommend routine screening for serum vitamin B12 and homocysteine in individuals with T2DM who take daily metformin doses higher than 2000 mg, or for a duration exceeding 4 years.

M.C.V. should not be the only criteria to order vitamin B12 for anemia under evaluation

Introduction: A strict vegetarian diet has been associated with increased risk of cobalamin deficiency therefore;one would expect a high prevalence of Cobalamin deficiency in India. Erythrocyte indices have been used in the initial evaluation of anemic patients;high Mean corpuscular volume (MCV) is a traditional criterion for folate and vitamin B12 deficiencies. There is no large study of the prevalence of B12 deficiency among patients with normocytosis or micro-cytosis. Method: We retrospectively analyzed the records of serum vitamin B12 and MCV of both inpatients and outpatients at Santokba Durlabhji Memorial Hospital & Research Institute, Jaipur (Rajasthan) during the period from August 2010-April 2011. The study was aimed at identifying the correlation between vitamin B12 level and MCV;and prevalence of vitamin B12 deficiency in this region. Result & Conclusion: Every third person is vitamin B12 deficient in the region. There is no correlation between vitamin B12 levels and MCV in majority of the cases. MCV should not be the only criteria for ordering vitamin B12 for patients with anemia under evaluation.