Diagnostic Performances of Urinary Methylmalonic Acid/Creatinine Ratio in Vitamin B12 Deficiency

Supakul, Sopak; Chabrun, Floris; Genebrier, Steve; M, N'Guyen; Valarche, Guillaume; Derieppe, A.; Villoteau, Adeline; Lacombe, Victor G.; Urbanski, G.

doi:10.3390/jcm9082335

Cited by 17 publications

(4 citation statements)

References 51 publications

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“…Measurements of plasma B12, plasma folate, and ferritin were systematically performed, and measurements of the other biomarkers of B12 deficiency (plasma homocysteine, plasma methylmalonic acid) were performed in case of plasma B12 between 201 and 350 ng/L. Indeed, where plasma B12 is in the low normal range, B12 deficiency must be assessed by measurements of other biomarkers because measuring plasma vitamin B12 alone is not enough to identify B12 deficiency [ 11 , 20 , 21 ].…”

Section: Methodsmentioning

confidence: 99%

Association of Primary Sjögren’s Syndrome and Vitamin B12 Deficiency: A Cross-Sectional Case-Control Study

Urbanski

Chabrun

Schaepelynck

et al. 2020

JCM

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Descriptive and retrospective studies without control groups have suggested a possible association between primary Sjögren’s syndrome (pSS) and vitamin B12 (B12) deficiency. This is of importance because several mucosal and neurological features are common to these two conditions and could be prevented or reversed in case of B12 deficiency. We aimed to evaluate the association between pSS and B12 deficiency. We prospectively assessed the B12 status of 490 patients hospitalized in an internal medicine department over a 15-week period. Patients with pernicious anemia were excluded. We extracted patients with pSS and paired them with controls according to age and sex, with a 1:5 ratio. Twenty-one pSS patients were paired with 105 control patients. The median age was 70 years old (51–75) and 95.2% of patients were women. The plasma B12 level was lower in pSS patients (329 (293–521) ng/L vs. 456 (341–587) ng/L, p < 0.0001). B12 deficiency was associated with pSS (42.9% among pSS patients vs. 11.4% among controls), even after adjustment for other causes of B12 deficiency (OR 6.45 (95%CI: 2.08–20.0)). In conclusion, pSS appeared to be associated with B12 deficiency, even after the exclusion of pernicious anemia. This justifies screening and treating B12 deficiency in pSS patients.

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Section: Methodsmentioning

confidence: 99%

Association of Primary Sjögren’s Syndrome and Vitamin B12 Deficiency: A Cross-Sectional Case-Control Study

Urbanski

Chabrun

Schaepelynck

et al. 2020

JCM

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“…52 Some authors have suggested replacing serum MMA with urinary MMA measurement, but in one study the number of individuals with zero urinary MMA was 30%, rendering this assay unreliable. 53 Serum tHcy is an alternative functional biomarker of B12 status but is also elevated in folate deficiency, vitamin B6 deficiency, impaired renal function, hypothyroidism, and by certain medications. 54 Thus, elevated serum MMA and/or tHcy may confirm the diagnosis of B12 deficiency, but in people with symptoms, normal concentrations of these biomarkers do not exclude this diagnosis.…”

Section: Holo-transcobalamin Mma And/or Homocysteinementioning

confidence: 99%

Section: Biochemical Diagnosis Of B12 Deficiencymentioning

confidence: 99%

A Brief Overview of the Diagnosis and Treatment of Cobalamin (B12) Deficiency

Wolffenbuttel,

McCaddon,

Ahmadi

et al. 2024

Food Nutr Bull

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Background: An increasing number of adult individuals are at risk of vitamin B12 deficiency, either from reduced nutritional intake or impaired gastrointestinal B12 absorption. Objective: This study aims to review the current best practices for the diagnosis and treatment of individuals with vitamin B12 deficiency. Methods: A narrative literature review of the diagnosis and treatment of vitamin B12 deficiency. Results: Prevention and early treatment of B12 deficiency is essential to avoid irreversible neurological consequences. Diagnosis is often difficult due to diverse symptoms, marked differences in diagnostic assays' performance and the unreliability of second-line biomarkers, including holo-transcobalamin, methylmalonic acid and total homocysteine. Reduced dietary intake of B12 requires oral supplementation. In B12 malabsorption, oral supplementation is likely insufficient, and parenteral (i.e. intramuscular) supplementation is preferred. There is no consensus on the optimal long-term management of B12 deficiency with intramuscular therapy. According to the British National Formulary guidelines, many individuals with B12 deficiency due to malabsorption can be managed with 1000 µg intramuscular hydroxocobalamin once every two months after the initial loading. Long-term B12 supplementation is effective and safe, but responses to treatment may vary considerably. Clinical and patient experience strongly suggests that up to 50% of individuals require individualized injection regimens with more frequent administration, ranging from daily or twice weekly to every 2-4 weeks, to remain symptom-free and maintain a normal quality of life. ‘Titration’ of injection frequency based on measuring biomarkers such as serum B12 or MMA should not be practiced. There is currently no evidence to support that oral/sublingual supplementation can safely and effectively replace injections. Conclusions: This study highlights the interindividual differences in symptomatology and treatment of people with B12 deficiency. Treatment follows an individualized approach, based on the cause of the deficiency, and tailored to help someone to become and remain symptom-free.

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“…Urinary MMA/creatinine ratio (uMMA/ C) may have diagnostic utility, due to the stable urinary excretion of MMA before severe renal failure [126]. With a threshold of 1.45 mmol/mmol, the uMMA/C ratio has been associated with good diagnostic performance for B 12 deficiency as a second line assay [127].…”

Section: Holotranscobalamin Testingmentioning

confidence: 99%

Vitamin B₁₂status in health and disease: a critical review. Diagnosis of deficiency and insufficiency – clinical and laboratory pitfalls

Sobczyńska‐Malefora

Delvin

McCaddon

et al. 2021

Critical Reviews in Clinical Laboratory Sciences

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Vitamin B 12 (cobalamin) is an essential cofactor for two metabolic pathways. It is obtained principally from food of animal origin. Cobalamin becomes bioavailable through a series of steps pertaining to its release from dietary protein, intrinsic factor-mediated absorption, haptocorrin or transcobalamin-mediated transport, cellular uptake, and two enzymatic conversions (via methionine synthase and methylmalonyl-CoA-mutase) into cofactor forms: methylcobalamin and adenosylcobalamin. Vitamin B 12 deficiency can masquerade as a multitude of illnesses, presenting different perspectives from the point of view of the hematologist, neurologist, gastroenterologist, general physician, or dietician. Increased physician vigilance and heightened patient awareness often account for its early presentation, and testing sometimes occurs during a phase of vitamin B 12 insufficiency before the main onset of the disease. The chosen test often depends on its availability rather than on the diagnostic performance and sensitivity to irrelevant factors interfering with vitamin B 12 markers. Although serum B 12 is still the most commonly used and widely available test, diagnostics by holotranscobalamin, serum methylmalonic acid, and plasma homocysteine measurements have grown in the last several years in routine practice. The lack of a robust absorption test, coupled with compromised sensitivity and specificity of other tests (intrinsic factor and gastric parietal cell antibodies), hinders determination of the cause for depleted B 12 status. This can lead to incorrect supplementation regimes and uncertainty regarding later treatment. This review discusses currently available knowledge on vitamin B 12 , informs the reader about the pitfalls of tests for assessing its deficiency, reviews B 12 status in various populations at different disease stages, and provides recommendations for interpretation, treatment, and associated risks. Future directions for diagnostics of B 12 status and health interventions are also discussed.

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Diagnostic Performances of Urinary Methylmalonic Acid/Creatinine Ratio in Vitamin B12 Deficiency

Cited by 17 publications

References 51 publications

Association of Primary Sjögren’s Syndrome and Vitamin B12 Deficiency: A Cross-Sectional Case-Control Study

Association of Primary Sjögren’s Syndrome and Vitamin B12 Deficiency: A Cross-Sectional Case-Control Study

A Brief Overview of the Diagnosis and Treatment of Cobalamin (B12) Deficiency

Vitamin B₁₂status in health and disease: a critical review. Diagnosis of deficiency and insufficiency – clinical and laboratory pitfalls

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Diagnostic Performances of Urinary Methylmalonic Acid/Creatinine Ratio in Vitamin B12 Deficiency

Cited by 17 publications

References 51 publications

Association of Primary Sjögren’s Syndrome and Vitamin B12 Deficiency: A Cross-Sectional Case-Control Study

Association of Primary Sjögren’s Syndrome and Vitamin B12 Deficiency: A Cross-Sectional Case-Control Study

A Brief Overview of the Diagnosis and Treatment of Cobalamin (B12) Deficiency

Vitamin B12status in health and disease: a critical review. Diagnosis of deficiency and insufficiency – clinical and laboratory pitfalls

Contact Info

Product

Resources

About

Vitamin B₁₂status in health and disease: a critical review. Diagnosis of deficiency and insufficiency – clinical and laboratory pitfalls