Methylmalonic Acid Blood Test

A methylmalonic acid blood test measures the levels of methylmalonic acid in the blood. Methylmalonic acid is a substance that is normally present in very small amounts in the body. Elevated levels of methylmalonic acid in the blood can indicate a deficiency in vitamin B12 or a condition known as methylmalonic acidemia, which is an inherited metabolic disorder.

This test is often used to help diagnose and monitor vitamin B12 deficiency, which can lead to symptoms such as fatigue, weakness, numbness and tingling in the hands and feet, and difficulty walking. A methylmalonic acid test may be ordered along with other tests such as a complete blood count, vitamin B12 level, and homocysteine level to help make a diagnosis.

It is important to follow any pre-test instructions given by your test provider, as certain factors like diet or medications can affect the results of the test. Results are typically reported as a numerical value.