Vitamin B 12 Deficiency (Vitamin B12 Deficiency)

A nutritional condition produced by a deficiency of VITAMIN B 12 in the diet, characterized by megaloblastic anemia. Since vitamin B 12 is not present in plants, humans have obtained their supply from animal products, from multivitamin supplements in the form of pills, and as additives to food preparations. A wide variety of neuropsychiatric abnormalities is also seen in vitamin B 12 deficiency and appears to be due to an undefined defect involving myelin synthesis. (From Cecil Textbook of Medicine, 19th ed, p848)

Also Known As:

Networked: 1264 relevant articles (26 outcomes, 129 trials/studies)

Relationship Network

Disease Context: Research Results

Related Diseases

1.	Anemia
2.	Stomach Neoplasms (Stomach Cancer)
3.	Infection
4.	Peptic Ulcer (Peptic Ulcers)
5.	Tinnitus

Experts

1.	Herrmann, Wolfgang: 12 articles (03/2013 - 01/2002)
2.	Nexo, Ebba: 11 articles (03/2013 - 11/2003)
3.	Andrès, Emmanuel: 10 articles (01/2013 - 10/2002)
4.	Obeid, Rima: 9 articles (02/2014 - 11/2003)
5.	Allen, Lindsay H: 8 articles (06/2015 - 06/2004)
6.	Sun, Andy: 7 articles (09/2015 - 07/2012)
7.	Wang, Yi-Ping: 7 articles (09/2015 - 07/2012)
8.	Andrès, E: 7 articles (01/2009 - 07/2000)
9.	Chen, Hsin-Ming: 6 articles (09/2015 - 06/2013)
10.	Clarke, Robert: 6 articles (01/2011 - 01/2004)

Drugs and Biologics

Drugs and Important Biological Agents (IBA) related to Vitamin B 12 Deficiency:

1.	Vitamin B 12 (Cyanocobalamin)FDA LinkGeneric 09/01/2014 - "Oral vitamin B12 treatment is effective for children with nutritional vitamin B12 deficiency." 10/01/2010 - "Is oral vitamin B(12) therapy effective for vitamin B(12) deficiency in patients with prior ileocystoplasty?" 10/01/2000 - "Vitamin B12 deficiency is effectively treated with oral vitamin B12 supplementation. " 11/01/2013 - "Intramuscular vitamin B12 continues to be the gold standard of therapy for vitamin B12 deficiency, especially in symptomatic patients. " 01/01/2012 - "Testing the total concentration of vitamin B12 alone has insufficient diagnostic accuracy and no accepted gold standard is available for diagnosing vitamin B12 deficiency. "
2.	Folic Acid (Vitamin M)FDA LinkGeneric 10/01/1973 - "Urinary excretion of (14)C indicated that renal clearance of folate may have been impaired in very severe vitamin B(12) deficiency. " 10/01/1984 - "None of these individuals showed any clinical signs of folate and/or vitamin B12 deficiency, and mean corpuscular volumes were not significantly greater than those for the entire population (90.8 +/- 4.1 fl). " 03/01/1982 - "Methyl-FH4 was effective in folate deficiency but not in vitamin B12 deficiency. " 10/01/2015 - "The objectives of this study were to describe the prevalence of folate and vitamin B12 deficiencies among women of childbearing age (WCBA) in Guatemala and to identify vulnerable populations at greater risk for nutrient deficiency. " 10/01/2014 - "No folate or vitamin B12 deficiency was identified throughout the study. "
3.	HomocysteineIBA 01/01/2014 - "In conclusion, findings of this study suggest that some OCD patients might have vitamin B12 deficiency and higher homocysteine levels. " 07/01/2009 - "Elevated total homocysteine (tHcy) levels may be caused by vitamin B12 deficiency and are linked to Alzheimers disease (AD) in some studies, although the evidence is mixed. " 04/18/2001 - "In vivo studies show that Vitamin B12 deficiency and elevated plasma homocysteine are significantly correlated with increased micronucleus formation. " 01/01/2001 - "The present study provides indirect support to the hypothesis that defects in the trans-sulphuration and remethylation of homocysteine produce hyperhomocysteinaemia in vitamin B(12) deficiency in human subjects. " 01/01/1977 - "The results of the study support the "methyltetrahydrofolate-trap" hypothesis in vitamin B12 deficiency, in which decreased activity of the methylocobalamin-dependent methyltransferase enzyme is believed to lead to accumulation of methyltetrahydrofolate and homocysteine in the deficient cells. "
4.	CreatinineIBA 02/01/2001 - "Vitamin B12 deficiency, defined as an increase in the MMA/creatinine ratio and TH normalized with B12, is highly prevalent among elderly subjects and may occur in absence of clinical and/or analytical manifestations. " 01/01/2014 - "In multivariate analysis, HHC was associated with male gender, vitamin B12 deficiency, clearance of creatinine, alcohol consumption, and hyperuricemia. " 09/01/1999 - "Urinary methylmalonic acid/creatinine ratio: a gold standard test for tissue vitamin B12 deficiency." 01/01/2005 - "An additional 14 patients (27%) with elevated MMA and cystathionine levels also had slightly elevated concentrations of creatinine, pointing to the need for discrimination between renal dysfunction and vitamin B12 deficiency in this group. "
5.	Methylmalonic AcidIBA 12/01/2015 - "Seventeen vegan or vegetarian adults (26-57 years of age) with a known vitamin B12 deficiency, as evidenced by a baseline serum methylmalonic acid (MMA) level above 270 nmol/L at screening, but who otherwise appeared healthy were enrolled in the study. " 03/01/2012 - "Methylmalonic acid (MMA) is considered as the most representative indicator of metabolic vitamin B(12) deficiency and is used as such in this study. " 01/01/2008 - "Recent studies have not investigated functional markers of vitamin B12 deficiency, such as methylmalonic acid. " 05/01/1987 - "If the high sensitivity and specificity of the gas chromatography-mass spectrometry assay for urinary methylmalonic acid is supported by other clinical studies, the methylmalonic acid assay may become the reference standard for the diagnosis of vitamin B12 deficiency." 01/01/1971 - "Clinical aspect of the studies of metabolic precursors of methylmalonic acid in vitamin B 12 deficiency."
6.	IronIBA 01/01/2015 - "In contrast, long-term use of PPI has been suggested to be associated with iron or vitamin B12 deficiency. " 11/01/2014 - " optimized multivitamin supplement is safe and reduces the development of iron and vitamin B12 deficiencies after LRYGB." 01/01/2014 - "Young age (p = 0.0120), poor preoperative iron status (p = 0.0004), vitamin B12 deficiency (p = 0.0009), and increasing time after surgery (p < 0.0001) were also associated with iron deficiency. " 05/01/2013 - "GPCA-positive patients had a significantly higher frequency of Hb, iron, or vitamin B12 deficiency and of abnormally high MCV (all P-values < 0.001) than healthy controls. " 08/01/2012 - "Consistent data are still missing to correctly assess the risk of iron deficiency, vitamin B12 deficiency or hypomagnesaemia and the risk of digestive malignant diseases, despite the pathophysiological basis that exists concerning gastric malignancy. "
7.	Aspirin (Acetylsalicylic Acid)FDA LinkGeneric 10/01/2004 - "Association of aspirin use with vitamin B12 deficiency (results of the BACH study)." 10/01/2004 - "In almost half of the study population, vitamin B(12) deficiency was found; patients using acetylsalicylic acid were more frequently vitamin B(12) deficient in comparison to nonusers (p = 0.02). " 03/01/2013 - "pylori should be sought and eradicated before starting NSAIDs treatment, in aspirin users with a history of gastroduodenal ulcer, and in patients presenting with chronic dyspepsia, high risk factors of gastric cancer, unexplained iron deficiency anaemia, vitamin B12 deficiency, or immune (idiopathic) thrombocytopenic purpura. "
8.	AcidsIBA 08/01/1968 - "The excretion of methylmalonic and formininoglutamic acids during the induction and remission of vitamin B12 deficiency in sheep." 10/01/1966 - "Blood pyruvic and alpha-oxoglutaric acids in vitamin B12 deficiency." 08/01/2007 - "Vitamin B (12) deficiency can easily be diagnosed by detection of methylmalonic acid when measuring the organic acids in urine. " 01/01/1967 - "Vitamin B12 deficiency and the excretion of ether-soluble acids in the rat." 04/01/1965 - "Vitamin B(12) deficiency resulted in higher concentrations of palmitic acid in the liver triglycerides on days 15, 17 and 19, higher concentrations of C(18) polyunsaturated acids on days 13 and 15 and lower concentrations of oleic acid on days 13, 15, 17 and 19. "
9.	mecobalamin (methylcobalamin)IBA 01/01/2015 - "Treatment of vitamin B12 deficiency-methylcobalamine? " 09/01/2003 - "Under the diagnosis of subacute combined degeneration (SCD) due to possible vitamin B12 deficiency, the treatment with intravenous injections of 500 micrograms/day of mecobalamin was undertaken. " 09/01/2012 - "We report a case of middle-aged man presenting with OCD, low serum cobalamin and a positive family history of vitamin B12 deficiency who responded well to methylcobalamin replacement." 05/01/2002 - "To examine whether functional vitamin B12 deficiency exists even in HD patients with normal vitamin B12 concentrations, 15 HD patients (serum vitamin B12 concentrations, 250 to 2,100 pg/mL) were treated with vitamin B12 (mecobalamin, 1.5 mg/d) for 8 weeks. " 02/06/1981 - "The need for methylcobalamin for the conversion of homocysteine to methionine and the requirement that myelin basic protein may be methylated, offer a rational explanation for the myelin lesions observed in cases of vitamin B12 deficiency where there is increasing evidence that methyl-, rather than adenosylcobalamin is required to prevent dysmyelination."
10.	Vitamin B Complex (B Vitamins)IBA 01/01/2014 - "Intake of vitamin B complex and multivitamins seems to protect from vitamin B12 deficiency. " 04/01/1977 - "A 17-year-old boy with vitamin B12 deficiency that occurred after a small bowel resection developed bilateral centrocecal scotomas during folic acid therapy and improved on therapy including vitamin B complex."

Therapies and Procedures

1.	Gastrectomy 08/01/2000 - "To examine the development of chemical and clinical vitamin B12 deficiency after total gastrectomy, and to evaluate the efficacy of supplemental oral B12 administration. " 12/01/2013 - "However, the clinical pattern of vitamin B12 deficiency development after gastrectomy remains unclear. " 01/01/2012 - "And vitamin B12 deficiency due to gastrectomy is one of the risk factors for cellular immunity impairment and was possibly to the false negative QFT and development of TB." 12/01/2011 - "Vitamin B12 deficiency is a common long-term sequelae after total gastrectomy. " 10/01/2011 - "It is important to suspect vitamin B12 deficiency in mothers who have undergone gastrectomy. "
2.	Intramuscular Injections 01/01/2013 - "This economic analysis aimed to estimate the cost savings of switching from intramuscular injections to high-dose oral supplements for patients aged 18 years and older with confirmed vitamin B12 deficiency. " 01/01/2013 - "In Canada, patients with vitamin B12 deficiency are typically given intramuscular injections, which incur considerable cost and inconvenience. " 03/15/1999 - "Vitamin B12 deficiency has traditionally been treated with intramuscular injections, although oral and intranasal preparations are also available. " 05/23/2005 - "Supplementation with high doses of oral cobalamin is as effective as cobalamin administered by intramuscular injection to correct plasma markers of vitamin B(12) deficiency, but the effects of lower oral doses of cobalamin on such markers are uncertain. " 01/01/2013 - "We evaluated the utility of serum MMA and holoTC for its role in the detection of vitamin B12 deficiency in dialysis patients (n=17) by using the reduction of MMA concentrations as a marker of the response to vitamin B12 treatment (1 mg, intramuscular injections once per month for 3 months). "
3.	Vegetarian Diet (Vegetarianism) 02/15/2013 - "Thus, our study reveals that vegetarian diet along with polymorphism in the FUT2 gene may contribute significantly to the high prevalence of vitamin B(12) deficiency in India." 05/01/2014 - "Vegetarians, regardless of the type of vegetarian diet they adhere to, should be screened for vitamin B12 deficiency. " 05/01/2014 - "Individuals following vegetarian diets are at risk for developing vitamin B12 deficiency owing to suboptimal intake. " 01/01/2012 - "Vegetarianism and consequent vitamin B12 deficiency may be associated with IR. " 10/19/2009 - "Both children suffered form anaemia and delayed development due to vitamin B12 deficiency caused by strict maternal vegan diet during pregnancy and nursing. "
4.	Aftercare (After-Treatment) 12/01/2011 - "Mean DNA damage scores in children with vitamin B(12) deficiency and their mothers were significantly higher before treatment than those after treatment. " 09/01/2009 - "After treatment was initiated, laboratory analysis of pre-treatment blood samples confirmed the presence of vitamin B(12) deficiency. " 07/16/2015 - "We aimed to investigate the effects of iron deficiency anemia (IDA) and vitamin B12 deficiency coexisting with IDA which is called as mixed anemia (MA) on hemorheological parameters, to compare them with each other and healthy controls, and to assess the changes in hemorheological parameters after treatment. " 05/01/1977 - "Serum C3 and C4 levels have been determined in patients with Addisonian pernicious anaemia (PA) and megaloblastic anaemia due to vitamin B12 deficiency from other causes, before and after treatment, in order to study the interaction between vitamin B12 deficiency and complement and the role of complement in the pathogenesis of the gastric lesion of PA. " 02/01/1966 - "Anemia due to vitamin B12 deficiency after treatment with folic acid in tropical sprue."
5.	Injections 01/01/2013 - "The child was diagnosed with presumed vitamin B12 deficiency and was treated with intramuscular B12 injections. " 10/17/2011 - "In Denmark, patients with vitamin B12 deficiency are usually treated for life with either Betolvex or Vibeden given as injections every third month. " 07/01/2009 - "Although, the traditional treatment for vitamin B12 deficiency has been intramuscular cobalamin injections, recent studies have shown that oral cobalamin may be as efficacious." 11/01/2006 - "Once the diagnosis of vitamin B12 deficiency has been confirmed efficient treatment can be ensured either by injections every 2-3 month or by a daily dose of 1 mg vitamin B12." 12/01/1995 - "Vitamin B12 deficiency is treatable with monthly injections, large doses of daily oral supplement tablets, or an intranasal gel, which is far better absorbed than comparable oral supplements."