Tags

Type your tag names separated by a space and hit enter

The usefulness of holotranscobalamin in predicting vitamin B12 status in different clinical settings.
Curr Drug Metab. 2005 Feb; 6(1):47-53.CD

Abstract

Serum concentrations of homocysteine (Hcy) and methylmalonic acid (MMA) become increased in B12-deficient subjects and are therefore, considered specific markers of B12 deficiency. Serum level of holotranscobalamin (holoTC) becomes decreased before the development of the metabolic dysfunction. We investigated the usefulness of holoTC in diagnosing B12 deficiency in some clinical settings. We measured serum concentrations of holoTC, MMA, Hcy and total B12 in omnivores, vegetarians, elderly people and haemodialysis patients. Our results indicated that the incidence of holoTC <35 pmol/L was highest in the vegans (76%). Low holoTC and elevated MMA were detected in 64% of the vegans and 43% of the lacto- and lacto-ovovegetarians. An elevated MMA and a low holoTC were found in subjects with total serum B12 as high as 300 pmol/L. The distribution of holoTC in elderly people was similar to that in younger adults (median holoTC 55 pmol/L in both groups). A low holoTC and an elevated MMA were found in 16% of the elderly group. An elevated MMA and a normal holoTC were found in 20% of the elderly group who had a relatively high median serum concentration of creatinine (106.1 micromol/L). Serum concentrations of holoTC in dialysis patients were considerably higher than all other groups (median 100 pmol/L). This was also associated with severely increased serum levels of MMA (median 987 nmol/L). From these results it can be concluded that serum concentration of holoTC is a much better predictor of B12 status than total B12. This was particularly evident in case of dietary B12 deficiency. Serum concentrations of holoTC as well as MMA can be affected by renal dysfunction. Elevated MMA and normal holoTC in patients with renal insufficiency may not exclude vitamin B12 deficiency. HoloTC seems not to be a promising marker in predicting B12 status in renal patients.

Authors+Show Affiliations

Herrmann W
Department of Clinical Chemistry, University Hospital of Saarland, 66421 Homburg, Germany. kchwher@uniklinik-saarland.de
Obeid R
No affiliation info available
Schorr H
No affiliation info available
Geisel J
No affiliation info available

MeSH

AdultAge FactorsAgedBiomarkersFemaleHumansKidney Failure, ChronicMaleMethylmalonic AcidMiddle AgedNutritional StatusRenal DialysisTranscobalaminsVitamin B 12Vitamin B 12 Deficiency

Pub Type(s)

Journal Article

Language

eng

PubMed ID

15720207

Citation

Herrmann, Wolfgang, et al. "The Usefulness of Holotranscobalamin in Predicting Vitamin B12 Status in Different Clinical Settings." Current Drug Metabolism, vol. 6, no. 1, 2005, pp. 47-53.
Herrmann W, Obeid R, Schorr H, et al. The usefulness of holotranscobalamin in predicting vitamin B12 status in different clinical settings. Curr Drug Metab. 2005;6(1):47-53.
Herrmann, W., Obeid, R., Schorr, H., & Geisel, J. (2005). The usefulness of holotranscobalamin in predicting vitamin B12 status in different clinical settings. Current Drug Metabolism, 6(1), 47-53.
Herrmann W, et al. The Usefulness of Holotranscobalamin in Predicting Vitamin B12 Status in Different Clinical Settings. Curr Drug Metab. 2005;6(1):47-53. PubMed PMID: 15720207.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - The usefulness of holotranscobalamin in predicting vitamin B12 status in different clinical settings. AU - Herrmann,Wolfgang, AU - Obeid,Rima, AU - Schorr,Heike, AU - Geisel,Jürgen, PY - 2005/2/22/pubmed PY - 2005/3/25/medline PY - 2005/2/22/entrez SP - 47 EP - 53 JF - Current drug metabolism JO - Curr Drug Metab VL - 6 IS - 1 N2 - Serum concentrations of homocysteine (Hcy) and methylmalonic acid (MMA) become increased in B12-deficient subjects and are therefore, considered specific markers of B12 deficiency. Serum level of holotranscobalamin (holoTC) becomes decreased before the development of the metabolic dysfunction. We investigated the usefulness of holoTC in diagnosing B12 deficiency in some clinical settings. We measured serum concentrations of holoTC, MMA, Hcy and total B12 in omnivores, vegetarians, elderly people and haemodialysis patients. Our results indicated that the incidence of holoTC <35 pmol/L was highest in the vegans (76%). Low holoTC and elevated MMA were detected in 64% of the vegans and 43% of the lacto- and lacto-ovovegetarians. An elevated MMA and a low holoTC were found in subjects with total serum B12 as high as 300 pmol/L. The distribution of holoTC in elderly people was similar to that in younger adults (median holoTC 55 pmol/L in both groups). A low holoTC and an elevated MMA were found in 16% of the elderly group. An elevated MMA and a normal holoTC were found in 20% of the elderly group who had a relatively high median serum concentration of creatinine (106.1 micromol/L). Serum concentrations of holoTC in dialysis patients were considerably higher than all other groups (median 100 pmol/L). This was also associated with severely increased serum levels of MMA (median 987 nmol/L). From these results it can be concluded that serum concentration of holoTC is a much better predictor of B12 status than total B12. This was particularly evident in case of dietary B12 deficiency. Serum concentrations of holoTC as well as MMA can be affected by renal dysfunction. Elevated MMA and normal holoTC in patients with renal insufficiency may not exclude vitamin B12 deficiency. HoloTC seems not to be a promising marker in predicting B12 status in renal patients. SN - 1389-2002 UR - https://www.unboundmedicine.com/medline/citation/15720207/The_usefulness_of_holotranscobalamin_in_predicting_vitamin_B12_status_in_different_clinical_settings_ DB - PRIME DP - Unbound Medicine ER -