The methylmalonic acid (MMA) blood test is generally used to help a medical provider determine if someone is suffering from a B12 deficiency. Although it isn’t a screening test to create a specific diagnosis, the medical community has suggested that in certain population demographics that it could be used as such. Seniors aged 65+ are the group most at-risk for having a Vitamin B12 deficiency, so frequent testing could help to uncover a health issue and treat is quickly. Not many doctors, however, use the MMA blood test for this purpose.
The MMA blood test is actually considered a fairly rare blood test, but not because of the fact that there is a rare or serious health issue that it detects. When paired with a homocysteine test, the MMA can help to explain certain physical symptoms that are associated with a B12 deficiency.
The methylmalonic acid blood test will also be ordered for newborns to determine if a rare metabolic order called methylmalonic acidemia is present. It is a mandatory screening test in all 50 states in the US.
When Is the MMA Blood Test Ordered?
The most common reason why the MMA blood test would be ordered in adults would be to measure the B12 levels in individuals who are taking long-term protein pump inhibiting medications. These medicines reduce stomach acid levels and help to prevent inflammation and irritation within the digestive tract, but they also limit the body’s ability to process B12. Since this vitamin helps to make red blood cells and works with DNA, it is necessary for proper health.
The most common symptom of a B12 deficiency is fatigue. There may also be a feeling of weakness or feeling light-headed. A sore tongue and pale skin are often noticed and a person may bruise or bleed easily. An occasional rapid heartbeat, trouble breathing, and changes in bowel movements may also be present. Some people complain of neuropathy symptoms, such as tingling sensations, pain or burning caused by the nerves, or even involuntary muscle spasms.
Because these symptoms are common to other health issues, frequent testing besides the MMA blood test will be ordered first as most people are able to get the right amount of this vitamin through their eating habits.
What Do My Test Results Mean?
The methylmalonic blood test will either come back as “normal” or show that there is a deficiency in the needed supplement. The deficiency that is indicated may be considered mild and indicate that there isn’t enough of the B12 being absorbed by the body, even if there are sufficient levels of the vitamin present in a person’s diet. It is not a common result, however, and is usually not even considered to be medically significant.
When the MMA blood test is ordered with the homocysteine blood test and it is the latter test that is positive, then this may indicate a folate deficiency instead. For women who are pregnant or expecting to become pregnant, this condition will be addressed by a medical provider immediately.
Newborns may have an MMA blood test that is severely elevated instead of there being the presence of a deficiency. The elevated results indicate the presence of an inherited metabolic condition that may require lifelong treatment. Elevated MMA tests in adults may also indicate that there is a deficiency in the B12 levels that may need to be addressed.
What Happens With Abnormal Results?
Many medical providers will take a wait and see approach with adults who have abnormal methylmalonic acid blood test results. Most results tend to be on the lower or higher end of the normal range, so there really aren’t any findings to suggest that a health problem exists. This is especially true if the homocysteine test was ordered as well and it’s results were normal.
If there are deficiencies found with the MMA, then B12 supplements may become necessary. Most people can take a standard over the counter supplement for this vitamin and have it stabilize levels. For those with severe deficiencies, however, a medical provider may order B12 shots to be given instead as this treatment instantly replenishes levels to their normal state.
For accurate results, a medical provider may ask that fasting occur for a specific amount of time before a blood sample is collected. This test may be uncommon, but the results can be profound for those who have bothersome physical symptoms with no explanation. Only a medical provider can interpret what any personal results are, so be sure to use this guide to ask questions about your methylmalonic blood test results and what they mean for you.