This blood test measures methylmalonic acid levels to help diagnose vitamin B12 deficiency after a B12 test is low or at the lower end of normal.
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Vitamins
Methylmalonic acid - serum
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Vitamin B12 is needed to convert methylmalonic acid to coenzyme A. In vitamin B12 deficiency methylmalonic acid will accumulate in the body rather than being converted to coenzyme A. Both active vitamin B12 and serum B12 levels can be normal in people with the symptoms and biochemical signs of vitamin B12 deficiency, particularly when B12 levels are towards the lower end of the normal range. Measuring blood levels of methylmalonic acid can help to establish whether there is an underlying B12 deficiency.
Special instructions
How to prepare for your test
Prepare for your Methylmalonic Acid (MMA) Blood Test by following these instructions. Do not take vitamin B12 for two weeks prior to this test. If your B12 is prescribed ask your doctor whether to stop.
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FAQs
Why measure methylmalonic acid?
Measuring raised methylmalonic acid levels in your blood or urine is a sensitive early indicator of a vitamin B12 deficiency. Vitamin B12 deficiency symptoms usually develop gradually but can worsen if the condition goes untreated. Symptoms of vitamin B12 deficiency include feeling faint, pale skin, and heart palpitations.
What is a Methylmalonic Acid Blood Test?
Our Methylmalonic Acid (MMA) Blood Test measures the level of methylmalonic acid in your blood, which may be helpful if you want an early indicator of a vitamin B12 deficiency.
What is methylmalonic acid?
Methylmalonic acid is produced in small amounts in the body and is necessary for metabolism and energy production. Vitamin B12 promotes the conversion of methylmalonyl CoA to succinyl Coenzyme A. If there is not enough vitamin B12 available in your body, then the concentration of methylmalonic acid begins to rise, increasing in the blood and urine.