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Published on: July 9, 2015
Relationship between methylmalonic acid and cobalamin in uremia
L Moelby1, K Rasmussen, T Ring
1Department of Nephro;ogy, Aalborg Hospital, Aalborg, Germany. moelby@dadlnet.dk
Kidney International
|January 5, 2000
Summary
In uremic patients, plasma methylmalonic acid levels inversely correlate with vitamin B12 (cobalamin) levels. Oral vitamin B12 supplementation effectively reduced methylmalonic acid, suggesting its utility in managing B12 depletion in dialysis patients.
Area of Science:
- Nephrology
- Nutritional Biochemistry
Background:
- Assessing the need for routine vitamin B12 supplementation in dialysis patients.
- Investigating the impact of switching from injectable to oral vitamin B12 therapy.
- Examining the relationship between cobalamin and methylmalonic acid in hemodialysis patients receiving regular intramuscular cobalamin injections.
Purpose of the Study:
- To evaluate the necessity of routine vitamin B12 supplementation.
- To study the effects of transitioning from injectable to oral vitamin B12 supplementation.
- To analyze the relationship between cobalamin and methylmalonic acid in uremic patients.
Main Methods:
- Monthly blood sampling over a nine-month period of cobalamin injection withdrawal.
- A subsequent three-month period of daily oral cyanocobalamin tablet administration (1 mg).
- Analysis of plasma cobalamin and methylmalonic acid concentrations.
Main Results:
- Plasma cobalamin levels decreased during the withdrawal period and rose significantly after oral supplementation.
- Methylmalonic acid concentrations increased during withdrawal and decreased significantly following oral cyanocobalamin.
- An inverse relationship was observed between plasma methylmalonic acid and cobalamin concentrations within patients.
Conclusions:
- A clear inverse relationship exists between methylmalonic acid and cobalamin in uremic patients.
- Vitamin B12 depletion occurred during the withdrawal period, despite most patients maintaining above-limit plasma cobalamin.
- Daily oral cyanocobalamin is effective, though higher doses might be beneficial.
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