| Coverage Policy Manual | |
| Policy #: | 2024023 |
| Category: | Laboratory |
| Initiated: | November 2024 |
| Last Review: | January 2025 |
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| Vitamin B12 and Methylmalonic Acid Testing | |
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| Description: |
Vitamin B12, also known as cobalamin, is a water-soluble vitamin required for proper red blood cell formation, key metabolic processes, neurological function, and DNA regulation and synthesis. Hematologic and neuropsychiatric disorders caused by a deficiency in B12 can often be reversed by early diagnosis and prompt treatment (Oh, 2003).
Methylmalonic acid (MMA) is produced from excess methylmalonyl-CoA that accumulates when Vitamin B12 is unavailable and is considered an indicator of functional B12 deficiency (Sobczynska-Malefora, 2014).
Holotranscobalamin (holoTC) is the metabolically active fraction of B12 and is an emerging marker of impaired vitamin B12 status (Langan, 2017).
RegulatoryStatus
The FDA has cleared numerous devices including needles, reagents, instrumentation, and imaging systems for use in prostate biopsy. Many labs have developed specific tests that they must validate and perform in house. These laboratory-developed tests (LDTs) are regulated by the Centers for Medicare and Medicaid (CMS) as high-complexity tests under the Clinical Laboratory Improvement Amendments of 1988 (CLIA ’88). LDTs are not approved or cleared by the U. S. Food and Drug Administration; however, FDA clearance or approval is not currently required for clinical use.
Coding
See CPT/HCPCS Code section below.
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Policy/ Coverage: |
This policy applies to health plans that utilize a routine laboratory management vendor, which include Arkansas Blue Cross and Blue Shield, Federal Employee Health Benefit Plan and Postal Service Health Benefit Plan, Health Advantage, and Octave Blue Cross and Blue Shield fully insured plans, including the Metallic and ARHOME plans and Complete/Complete Plus plans. Additionally, this policy will apply to the Farm Bureau and Level Funded plans.
Meets Primary Coverage Criteria Or Is Covered For Contracts Without Primary Coverage Criteria
Total vitamin B12 testing or methylmalonic acid testing meets member benefit certificate primary coverage criteria that there be scientific evidence of effectiveness in improving health outcomes once every 3 months when the following criteria are met:
Does Not Meet Primary Coverage Criteria Or Is Investigational For Contracts Without Primary Coverage Criteria
Screening for vitamin B12 deficiency, for any indication or circumstance not described above, does not meet member benefit certificate primary coverage criteria that there be scientific evidence of effectiveness in improving health outcomes including but not limited to screening in asymptomatic individuals.
For members with contracts without primary coverage criteria, screening for vitamin B12 deficiency, for any indication or circumstance not described above, including but not limited to, screening in asymptomatic individuals, is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Homocysteine testing for the confirmation of vitamin B12 deficiency does not meet member benefit certificate primary coverage criteria that there be scientific evidence of effectiveness in improving health outcomes.
For members with contracts without primary coverage criteria, homocysteine testing for the confirmation of vitamin B12 deficiency is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Holotranscobalamin testing for screening, testing, or confirmation of vitamin B12 deficiency does not meet member benefit certificate primary coverage criteria that there be scientific evidence of effectiveness in improving health outcomes.
For members with contracts without primary coverage criteria, holotranscobalamin testing for screening, testing or confirmation of vitamin B12 deficiency is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Total vitamin B12 (serum cobalamin) testing, for any indication or circumstance not described above, does not meet member benefit certificate primary coverage criteria that there be scientific evidence of effectiveness in improving health outcomes.
For members with contracts without primary coverage criteria, total vitamin B12 (serum cobalamin) testing, for any indication or circumstance not described above, is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
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| Rationale: |
Vitamin B12 cannot be synthesized by human cells (Means Jr, 2023); rather, it is obtained from animal-derived dietary sources, such as meat, eggs, and dairy products (Hunt, 2014), as well as fortified cereals and supplements (Zeuschner, 2013). Vitamin B12 deficiency is classically caused by pernicious anemia; however, with modern fortification of western diets, this condition now accounts for only a minority of cases and currently occurs most often due to malabsorption (Means Jr, 2023).
The prevalence of vitamin B12 deficiency in the United States and United Kingdom is approximately 6% in persons younger than 60 years, reaching 20% in those older than 60 years. On the contrary, the prevalence is approximately 40% in Latin America, 70% in Kenyan school children, 80% in East Indian preschool-aged children, and 70% in East Indian adults (Hunt, 2014). Risk factors for deficiency include: decreased ileal absorption (Crohn disease, ileal resection, tapeworm infection), decreased intrinsic factor (atrophic gastritis, pernicious anemia, post-gastrectomy syndrome), genetic defects (transcobalamin II deficiency), inadequate intake (alcohol abuse, patients older than 75 years, vegans, or strict vegetarians), prolonged medication use (histamine H2 blocker use for more than 12 months, metformin use for more than four months, proton pump inhibitor use for more than 12 months) (Langan, 2017).
Vitamin B12 plays an essential role in nucleic acid synthesis. Deficiency can result in cell cycle arrest in the S phase or cause apoptosis (Green, 2017) and ultimately bone marrow failure and demyelinating nervous system disease (Stabler, 2013). Vitamin B12 is also critical in the remethylation of homocysteine (Hcy), and deficiency in Vitamin B12 can lead to hyperhomocysteinemia, a condition that has been associated with various cancers, such as breast and ovarian cancers, as well as Parkinson disease (Fan, 2020; Hama, 2020).
Clinical manifestations of Vitamin B12 deficiency vary in their presence and severity from mild fatigue to severe neurologic impairment (Langan, 2017). Mild deficiency can present as fatigue and anemia with an absence of neurological features. Moderate deficiency may include obvious macrocytic anemia with some mild or subtle neurological features. Severe deficiency shows evidence of bone marrow suppression, clear evidence of neurological features, and risk of cardiomyopathy. Recent literature also suggests a relationship between Vitamin B12 and depression (Sangle, 2020).
Vitamin B12 deficiency can cause glossitis and other gastrointestinal symptoms that vary with underlying diseases, such as inflammatory bowel disease or celiac disease (Means Jr, 2023). Early detection and correction of vitamin B12 deficiency with supplementation prevents progression to macrocytic anemia, elevated homocysteine (Hcy), potentially irreversible peripheral neuropathy, memory loss, and other cognitive deficits (Sobczynska-Malefora, 2014).
Analytical Validity
Both the clinical recognition of vitamin B12 deficiency and confirmation of the diagnosis by means of testing can be difficult. Several laboratory measures reflecting physiological, static, and functional B12 status have been developed (Hunt, 2014); however, there is no universally agreed upon gold standard assay for determining cobalamin levels in humans. The current convention is to estimate the abundance of vitamin B12 using total serum vitamin B12, despite the low sensitivity of this test (Sobczynska-Malefora, 2014). Two reportedly highly sensitive vitamin B12 deficiency markers are elevated levels of serum homocysteine and methylmalonic acid, but testing is expensive, and many other conditions may cause an elevation in these markers, including familial hyperhomocysteinemia, folate deficiency, levodopa therapy, and renal insufficiency (Langan, 2011). Serum methylmalonic acid levels tend to be just as sensitive but more specific than serum homocysteine levels in regards to vitamin B12 deficiency testing, highlighting the former as the preferred testing method by many (Langan, 2011).
An in-depth meta-analysis by Willis et al. (2011) of serum cobalamin testing included data from 54 different studies. The variability for sensitivity and specificity across the different studies ranged from 13% to 75% for sensitivity and 45% to 100% for specificity, depending on the reference standard used. Researchers conclude that “from the available evidence, diagnosis of conditions amenable to cbl [vitamin B12] supplementation on the basis of cbl [vitamin B12] level alone cannot be considered a reliable approach to investigating suspected vitamin deficiency” (Willis, 2011). The test measures total serum cobalamin including both serum holohaptocorrin and serum holotranscobalamin, which may mask true deficiency or falsely imply a deficient state (Hunt, 2014).
Vitamin B12 deficiency is present in both infant and pregnant individuals, and monitoring vitamin B12 levels is important in determining maternal and fetal health and growth. Low vitamin B12 levels during pregnancy are associated with a greater risk of preterm birth (Rogne, 2017). It seems that current pregnancy-specific cutoffs for vitamin B12 biomarkers are inadequate in the medical field (Schroder, 2019). Recently, a new study has identified a novel cutoff value in the vitamin B12 serum of newborns; the B12-related metabolite known as homocysteine (Hcy) is now recommended to have a cutoff value at “4.77 µmol/L (68.4% sensitivity, 58.3% specificity, p = .012) for the detection of vit-B12 deficiency” (Yetim, 2019). Other pregnancy specific B12 biomarkers have been published. According to another study, “The central 95% reference interval limits indicated that serum total B-12 <89.9 and <84.0 pmol/L, holoTC <29.5 and <26.0 pmol/L and MMA >371 and >374 nmol/L, in the first and second trimesters, respectively, may indicate B-12 deficiency in pregnant women. The lower limits of total B-12 and holoTC and the upper limits of MMA significantly differed by ethnicity in both trimesters. According to the change point analysis, total B-12 <186 and <180 pmol/L and holoTC <62.2 and <67.5 pmol/L in the first and second trimesters, respectively, suggested an increased probability of impaired intracellular B-12 status, with no difference between ethnicities” (Schroder, 2019).
Elevated levels of downstream metabolites, MMA and Hcy, are commonly used as adjuvant diagnostics to confirm a suspected diagnosis of cobalamin deficiency (Berg, 2013). The sensitivity of elevated serum MMA measurements in detecting patients with overt cobalamin deficiency is reported to be >95%; however, the specificity of this test has not been determined (Hunt, 2014). In a 2020 study to evaluate targeted newborn screening, the cutoff for MMA as an indicator of B12 deficiency was 0.423 µM with a specificity of 0.90 and sensitivity of 0.91 in newborns; “applying a screening algorithm including only tHCy [total homocysteine] as a second-tier test that may be feasible for many newborn screening labs, newborns with low VitB12, low HoloTC, or elevated MMA can be identified with a positive predictive value between 59% and 87%” (Rozmarič, 2020).
Serum holoTC may be a better indicator of B12-deficiency than serum cobalamin because it represents the biologically active fraction of cobalamin in humans and may be depleted first in subclinical cobalamin deficiency. HoloTC measurements appear to have slighter better sensitivity; however, the specificity of this assay remains to be determined (Oberley, 2013). It also is not yet clinically validated or available for widespread use (Langan, 2017).
Mak and others developed a targeted metabolite panel aiming to improve second-tier newborn screening for four inherited metabolic disorders: glutaric acidemia type I, methylmalonic acidemia, ornithine transcarbamylase deficiency, and very long-chain acyl-CoA dehydrogenase deficiency. The panel was assembled from “known disease markers and new features discovered by untargeted metabolomics” and is used to test dried blood samples. The authors completed a validation study on 883 infants. As a second-tier analysis method, the test had 100% screening sensitivity and an 84.5% reduction rate of MMA false positives. The authors conclude that “these findings establish the effectiveness of this second-tier test to improve screening for these four conditions” (Mak, 2023).
Clinical Utility and Validity
Health Quality Ontario (HQO) performed an extensive meta-analysis of the clinical utility of B12 testing in patients with suspected dementia or cognitive decline because more than 2.9 million serum B12 tests were performed in Ontario alone in 2010 (HQO, 2013). HQO included data from eighteen different studies to address three questions:
They concluded that “This evidence-based analysis assessed the usefulness of serum vitamin B12 testing as it relates to brain function. This review found very low-quality evidence that suggests a connection between high plasma homocysteine levels (a by-product of B vitamin metabolism in the body) and the onset of dementia. Moderate quality of evidence indicates treatment with vitamin B12 does not improve brain function. Moderate quality of evidence also indicates treatment using oral vitamin B12 supplements is as effective as injections of vitamin B12” (HQO, 2013).
Another meta-analysis, completed in 2015, utilized data from 12 studies and a total of 34,481 patients to determine if vitamin B12, vitamin B6, and folic acid supplementation affected homocysteine levels and/or reduced the risk of cardiovascular disease (Li et al., 2015). A combination of vitamin B12, vitamin B6, and folic acid was found to significantly reduce plasma homocysteine levels, but it did not seem to impact cardiovascular disease risk (Li et al., 2015). Therefore, it was concluded that vitamin B12 should not be utilized as a cardiovascular disease prevention method. Additional research has also concluded that the “Use of vitamin B12 in patients with elevated serum homocysteine levels and cardiovascular disease does not reduce the risk of myocardial infarction or stroke, or alter cognitive decline” (Langan, 2017).
In other indications, vitamin B12 has recently been utilized as a biomarker for patients undergoing therapeutic treatment for tuberculosis (TB); vitamin B12 serum concentrations were observed to have significant differences in TB patients between baseline and six months after anti-TB treatment (ATT), attributing the decrements in vitamin B12 to the body “reclaiming normal physiological function of the affected organs and immune function improv[ing] by cleaning or a rapid drop in bacterial load” (Gebremicael, 2019). Gebremicael and colleagues (2019) also found that HIV (Human Immunodeficiency Virus) and HAART (Highly active antiretroviral therapy) status of TB patients at baseline had “no effect on the concentration levels of vitamin B12 and vitamin A,” and HAART treatment did not affect vitamin B12 serum concentration in ATT treated HIV+/TB+ patients.
Wolffenbuttel and others, conducted a study obtaining data from the general population of National Health and Nutrition Examination Survey (NHANES). A total of 24462 patients were included. The authors found a positive association between low serum B12 concentration and all-cause mortality (hazard ratio [HR] = 1.39), as well as between low serum B12 concentration and cardiovascular mortality (HR = 1.64). The authors also found a positive association of high serum B12 concentration and cardiovascular mortality (HR = 1.45), although the authors noted that participants with diagnoses such as hyperlipidemia and CVD tended to use vitamin B12-containing supplements more often than those without such diagnoses. However, the authors did not find an association between vitamin B12 supplement intake and mortality. This demonstrates the importance of testing for B12 in the long run to adjust dietary intake and reduce mortality (Wolffenbuttel, 2020).
Sasaki et al. (2023) studied the usefulness of the one-hour ¹³C-propionate breath test in detecting Vitamin B12. The ¹³C-propionate breath test can use vitamin B12 as a coenzyme of methylmalonyl-CoA in propionate metabolism to measure vitamin B12 deficiency. The authors collected samples from 49 patients in Japan with clinically suspected vitamin B12 deficiency and compared results between patients with or without low serum vitamin B12 levels, macrocytosis, and vitamin B12 supplementation. The results have no significant difference between the patients with or without low serum VB12 levels. The results did have significant differences between patients with and without macrocytosis and between patients before and after vitamin B12 supplementation (Sasaki, 2023).
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| References: |
American Diabetes Assoc Professional Practice, C(2023a)(2024) Prevention or Dealy of Diab and Associated Comorbidities: Standards of Care in Diab. Diabetes Care, 47(Supplement_1), S43-S51. https://doi.org/10.2337/dc24-S003 APA(2023) Practice Guideline for the Treatment of Patients With Eating Disorders. Fourth Edition. https://psychiatryonline.org/doi/book/10.1176/appi.books.9780890424865 BCMA(2023) Cobalamin (vitamin B12) and Folate Deficiency. British Columbia Medical Association. Retrieved October 26 https://www2.gov.bc.ca/gov/content/health/practitioner-professional-resources/bc-guidelines/vitamin-b12 Berg, R. L., Shaw, G. R.(2013) Laboratory evaluation for vitamin B12 deficiency: the case for cascade testing. Clin Med Res, 11(1), 7-15. https://doi.org/10.3121/cmr.2012.1112 Devalia,V, Hamilton, MS, Molloy, AM(2014) Guidelines for the diagnosis and treatment of cobalamin and folate disorders. Br J Haematol, 166(4), 496-513. https://doi.org/10.1111/bjh.12959 Fan,X, Zhang,L, Li,H, et al.(2020) Role of homocysteine in the development and progression of Parkinson's disease. Ann Clin Transl Neurol. https://doi.org/10.1002/acn3.51227 Garber AJ, HandelsmanY, Grunberger G, et al.(2020) Consensus Statement by the AA of Clinical Endocrinologists and AC of Endocrinology on the Comprehensive Type 2 Diabetes Management Algorithm Executive Summary. Endocr Pract, 26(1), 107-139. https://doi.org/10.4158/CS-2019-0472 Gebremicael,G, Alemayehu,M, Sileshi,M, et al.(2019) The serum concentration of vitamin B12 as a biomarker of therapeutic response in tuberculosis patients with and without human immunodeficiency virus (HIV) infection. Int J Gen Med, 12, 353-361. https://doi.org/10.2147/ijgm.S218799 Gonzalez-Campoy JM, St Jeor ST,Castorino K, et al.(2013) Clinical practice guidelines for healthy eating for the prevention and treatment of metabolic and endocrine diseases in adults: cosponsored by the AA of Clinical Endocrinologists/the AC of Endocrinology and the Obesity Society. Endocr Pract, 19 Suppl 3, 1-82. https://doi.org/10.4158/ep13155.gl Green, R.(2017) Vitamin B12 deficiency from the perspective of a practicing hematologist. Blood, 129(19), 2603-2611. https://doi.org/10.1182/blood-2016-10-569186 Hama Y, Hamano T, Shirafuji N, et al.(2020) Influences of Folate Supplementation on Homocysteine and Cognition in Patients with Folate Deficiency and Cognitive Impairment. Nutrients, 12(10). https://doi.org/10.3390/nu12103138 HQO(2013) Vitamin B12 and cognitive function: an evidence-based analysis. Ont Health Technol Assess Ser, 13(23), 1-45. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3874776/ Huemer M, Diodato D, Schwahn B, et al.(2017) Guidelines for diagnosis and management of the cobalamin-related remethylation disorders cblC, cblD, cblE, cblF, cblG, cblJ and MTHFR deficiency. J Inherit Metab Dis, 40(1), 21-48. https://doi.org/10.1007/s10545-016-9991-4 Hunt, A., Harrington, D., & Robinson, S. (2014). Vitamin B12 deficiency. Bmj, 349, g5226. https://doi.org/10.1136/bmj.g5226 Langan R C, Zawistoski K J.(2011) Update on vitamin B12 deficiency. Am Fam Physician, 83(12), 1425-1430. https://pubmed.ncbi.nlm.nih.gov/21671542/ Langan, R C, Goodbred A J.(2017) Vitamin B12 Deficiency: Recognition and Management. Am Fam Physician, 96(6), 384-389. https://pubmed.ncbi.nlm.nih.gov/28925645 Li J, Li B, Qi J, Shen B.(2015) Meta-analysis of clinical trials of folic acid, vitamin B12 and B6 supplementation on plasma homocysteine level and risk of cardiovascular disease Zhonghua Xin Xue Guan Bing Za Zhi, 43(6), 554-561 Mak J, Peng G, Le A, et al.(2023) Validation of a targeted metabolomics panel for improved second-tier newborn screening. J Inherit Metab Dis, 46(2), 194-205. https://doi.org/10.1002/jimd.12591 Means Jr RT, Fairfield, KM.(2023) Causes and pathophysiology of vitamin B12 and folate deficiencies. Retrieved October 20 https://www.uptodate.com/contents/causes-and-pathophysiology-of-vitamin-b12-and-folate-deficiencies?source=see_link Mechanick JI, Apovian C, Brethauer S, et al.(2019) Clinical practice guidelines for the perioperative nutrition, metabolic, and nonsurgical support of patients undergoing bariatric procedures. Cosponsored by AA of Clin Endocrinologist/AC of Endocrinology, Obesity Society, AS for Metabolic & Bariatric Surg, Obesity Med Association and AS of Anesth. Ex Summary,EndocrPract, 25(12) 1346-1359, https://doi.org/10.4158/gl-2019-0406 O'Kane M, Parretti HM, Pinkney J, et al.(2020) British Obesity and Metabolic Surgery Society Guidelines on perioperative and postoperative biochemical monitoring and micronutrient replacement for patients undergoing bariatric surgery Obesity Reviews, 21(11), e13087. https://doi.org/10.1111/obr.13087 Oberley MJ, Yang D T(2013) Laboratory testing for cobalamin deficiency in megaloblastic anemia. Am J Hematol, 88(6), 522-526. https://doi.org/10.1002/ajh.23421 Oh R, Brown DL.(2003) Vitamin B12 deficiency. Am Fam Physician, 67(5), 979-986. https://pubmed.ncbi.nlm.nih.gov/12643357 Parrott J, Frank L, Rabena R, Craggs-Dino L, Isom K, Greiman L.(2017) AS for Metabolic and Bariatric Surgery Integrated Health Nutritional Guidelines for the Surgical Weight Loss Patient 2016 Update: Micronutrients. Surg Obes Relat Dis, 13(5), 727-741. Patient 2016 Update.(2016) Micronutrients Surg Obes Relat Dis, 13(5), 727-741. https://doi.org/10.1016/j.soard.2016.12.018 Pratt JSA, Browne A, Browne NT, et al.(2018) ASMBS pediatric metabolic and bariatric surgery guidelines. Surg Obes Relat Dis, 14(7), 882-901. https://doi.org/10.1016/j.soard.2018.03.019 Rogne T, Tielemans MJ, Chong MF, et al.(2017) Assoc of Maternal Vitamin B12 Concentration in Pregnancy With the Risks of Preterm Birth and Low Birth Weight: A Systematic Review and Meta-Analysis of Individual Participant Data. Am J Epidemiol, 185(3), 212-223. https://doi.org/10.1093/aje/kww212 Rozmaric T, Mitulovic G, Konstantopoulou V, et al.(2020) Elevated Homocysteine after Elevated Propionylcarnitine or Low Methionine in Newborn Screening Is Highly Predictive for Low Vitamin B12 and Holo-Transcobalamin Levels in Newborns. Diagnostics (Basel), 10(9). https://doi.org/10.3390/diagnostics10090626 Rubio-Tapia A, Hill ID, Kelly CP, Calderwood AH, Murray JA.(2013) ACG clinical guidelines: diagnosis and management of celiac disease. Am J Gastroenterol, 108(5), 656-676; quiz 677. https://doi.org/10.1038/ajg.2013.79 Sangle P, Sandhu O, Aftab Z, Anthony AT, Khan S.(2020) Vitamin B12 Supplementation: Preventing Onset and Improving Prognosis of Depression. Cureus, 12(10), e11169. https://doi.org/10.7759/cureus.11169 Sasaki Y, Sato T, Maeda T, et.al.(2023) Evaluation of the One-Hour C-Propionate Breath Test in 49 Patients from a Single Center in Japan to Detect Vitamin B12 Deficiency. Med Sci Monit, 29, e940238. https://doi.org/10.12659/msm.940238 Schroder TH, Tan A, Mattman A, et al.(2019) Reference intervals for serum total vitamin B12 and holotranscobalamin concentrations and their change points with methylmalonic acid concentration to assess vitamin B12 status during early and mid-pregnancy. Clin Chem Lab Med. https://doi.org/10.1515/cclm-2018-1337 Sobczynska-Malefora A, Gorska R, Pelisser M, et al.(2014) An audit of holotranscobalamin ("Active" B12) and methylmalonic acid assays for the assessment of vitamin B12 status: application in a mixed patient population. Clin Biochem, 47(1-2), 82-86. https://doi.org/10.1016/j.clinbiochem.2013.08.006 Stabler SP.(2013) Clinical practice. Vitamin B12 deficiency. N Engl J Med, 368(2), 149-160. https://doi.org/10.1056/NEJMcp1113996 Willis CD, Elshaug AG, Milverton JL, et al.(2011) Diagnostic performance of serum cobalamin tests: a systematic review and meta-analysis. Pathology, 43(5), 472-481. https://doi.org/10.1097/PAT.0b013e3283486435 Wolffenbuttel BHR, Heiner-Fokkema MR, Green R, Gans ROB.(2020) Relationship between serum B12 concentrations and mortality: experience in NHANES. BMC Medicine, 18(1), 307. https://doi.org/10.1186/s12916-020-01771-y Yetim A, Aygun E, Yetim C, et al.(2019) Measurement of serum vitamin B12-related metabolites in newborns: implications for new cutoff values to detect B12 deficiency. J Matern Fetal Neonatal Med, 1-9. https://doi.org/10.1080/14767058.2019.1633301 Zeuschner CL, Hokin BD, Marsh KA, Saunders AV, Reid MA, Ramsay MR.(2013) Vitamin B(1)(2) and vegetarian diets. Med J Aust, 199(4 Suppl), S27-32. https://pubmed.ncbi.nlm.nih.gov/25369926/ |
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Group specific policy will supersede this policy when applicable. This policy does not apply to the Wal-Mart Associates Group Health Plan participants or to the Tyson Group Health Plan participants.
CPT Codes Copyright © 2025 American Medical Association. |
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