SerumMethylmalonsäure

SerumMethylmalonsäure refers to the concentration of methylmalonic acid (MMA) in the blood serum. Methylmalonic acid is a small molecule produced during the metabolism of certain amino acids, specifically valine, isoleucine, threonine, and methionine. It is also a byproduct of the breakdown of odd-chain fatty acids. In the body, MMA is normally converted into succinyl-CoA, an intermediate in the citric acid cycle, with the help of vitamin B12 (cobalamin) as a cofactor.

Elevated levels of serum methylmalonic acid are a sensitive indicator of vitamin B12 deficiency. When vitamin B12 is deficient, the conversion of MMA to succinyl-CoA is impaired, leading to its accumulation in the blood. This elevation can be detected even before overt clinical signs of B12 deficiency become apparent. Therefore, serum MMA measurement is a valuable diagnostic tool for assessing vitamin B12 status.

Besides vitamin B12 deficiency, increased serum MMA levels can also be observed in other conditions, although less commonly. These include certain metabolic disorders, kidney disease, and in some cases, pregnancy. However, vitamin B12 deficiency remains the primary cause for clinically significant elevations in serum methylmalonic acid. The measurement of serum MMA is typically performed using chromatographic techniques.