When you purchase the B12 Vitamin Deficiency Testing Service, you will receive a sample collection kit that includes a sealable cup for urine collection and transportation, a plastic sleeve to keep the sample cup in during shipping, a prepaid, pre-addressed mailing envelope and a chain of custody form. The sample will be analyzed at a laboratory.
Early signs and symptoms of B12 deficiency may include loss of appetite, diarrhea, numbness and tingling of hands and feet, paleness, tiredness and decreased concentration and memory. So, if you have a vitamin B12 concentration in the low end of the normal range or if you have any of the aforementioned symptoms, you should consider getting yourself tested for B12 deficiency.
The uMMA-based Vitamin B12 Deficiency Detection service is an accurate, specific/sensitive, cost-effective and easy-to-use screening that can be used in the convenience of your home to screen samples for Vitamin B12 (cobalamin) deficiency.
This service measures methylmalonic acid (MMA) in urine samples. MMA is a compound produced in very small amounts during amino acid metabolism. Increased amounts of MMA in urine serves as a sensitive and early indicator of vitamin B12 deficiency (See "Biology Behind the Test" for more details).
This test is potentially beneficial for physicians and hospitals to make a judgment diagnosis for symptoms associated with vitamin B12 deficiency, ideally if done along with a homocysteine test. It is also very useful for individuals desiring to be tested by mail from the privacy of their home and investigators or research students seeking to screen a large number of samples for Vitamin B12 deficiency. The Vitamin B12 Deficiency Detection Service employs highly selected ion monitoring isotope dilution gas chromatography coupled with mass spectrometry (GC/MS) in a random spot urine specimen.
Biology Behind the Test:
Urine MMA levels are directly related to a B12-dependent metabolic pathway. Normally, vitamin B12 acts as a coenzyme, promoting the conversion of methylmalonyl CoA to succinic acid in a metabolic pathway: MMCoA (coenzyme B12) succinic acid. If there is not enough B12 available to act as a coenzyme, then methylmalonyl CoA concentrations begin to rise, and the body converts the methylmalonyl CoA to MMA instead. Decreased availability of B12 leads to increases in blood and urine MMA levels.
Blood/serum MMA-based tests are falsely high in renal insufficiency and intravascular volume depletion while blood/serum B12 tests are mere indicators of the amount of circulating B12 in serum. On the other hand, urinary MMA (uMMA) based test is a functional test as it is an indicator of the amount of tissue or cellular B12 available for physiological activity and thus gives biologically more relevant results. This test is also better than the Schilling Test, which is falsely normal in individuals who are unable to absorb food-bound B12 but can absorb crystalline B12.
Note to New York State Residents
New York State health law prohibits the testing of specimens collected in or mailed from New York, and prohibits the transmission of data from the laboratory to NY physicians or residents. Therefore, direct receipt of lab results for NY residents is not possible.
B12 Vitamin Testing Methodology
The laboratory analyzes the sample with urinary methylmalonic acid (uMMA) by gas chromatography - mass spectrometry (GC-MS) using the selected ion monitoring mode with deuterated MMA as an internal standard. The normal value is less than 3.8 micrograms of MMA per milligram creatinine.
- It is important to note that the use MMA testing may not be suitable for periodic monitoring purposes because it is subject to variation and results may not reliably trend up or down in response to B12 treatment.
- SPECIAL NOTICE This is a pre-paid test, if you lose any portion of this test we are unable to replace it.
- You are responsible for all shipping fees to send the sample to the laboratory. We highly suggest using a traceable method to ensure the sample does not get lost.
- It is important to note that MMA based B12 deficiency tests may be sensitive without being specific in certain cases. It has been found in certain studies that 20-25% of patients over the age of 70 have elevated levels of MMA, but 25-33% of them do not have B12 deficiency! For this reason, MMA is not routinely recommended in the elderly.
- An elevated MMA test may indicate a B12 deficiency, but the amount of MMA measured does not necessarily reflect the severity of the deficiency, its likelihood of progressing or the presence or severity of any symptoms.
- This test is not intended to make diagnosis or replace the medical advice and/or treatment obtained from a qualified healthcare practitioner. Please see your doctor with your results.
The Chain of Custody Form is valid for one year after the date of purchase.