Methylmalonic Acid (Serum)
Private serum Methylmalonic Acid testing in London for £268, measuring one functional Vitamin B12 marker with results expected in around 5 days.
Turnaround time
5 business days
Biomarkers count
1
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Overview of the Methylmalonic Acid (Serum) Test
The Methylmalonic Acid (Serum) blood test measures MMA circulating in serum, providing a sensitive functional marker of Vitamin B12-dependent metabolism.
The test assesses 1 specialist biochemical biomarker: Methylmalonic Acid - Serum.
Vitamin B12 is required by an enzyme involved in converting methylmalonyl-CoA into succinyl-CoA.
When Vitamin B12 availability is insufficient, Methylmalonic Acid accumulates.
A raised Serum MMA can therefore support evidence of functional B12 deficiency.
This can be particularly useful where Total Vitamin B12 is borderline or where symptoms remain suspicious despite an apparently inconclusive standard B12 result.
Serum MMA is not simply another measurement of the vitamin itself.
It assesses the biochemical consequence of inadequate cellular B12 activity.
MMA is relatively specific to Vitamin B12 compared with Homocysteine, which can also rise with Folate deficiency and several other conditions.
However, kidney function is an important limitation.
MMA is cleared partly through the kidneys.
Reduced renal function can therefore increase Serum MMA independently of Vitamin B12 deficiency.
Age and other metabolic factors can also influence concentrations.
For this reason, Creatinine and eGFR should be considered when an MMA result is elevated.
Vitamin B12 treatment can lower MMA relatively quickly.
A result obtained after injections or significant supplementation may therefore no longer reflect the untreated state.
The test is most valuable when interpreted with symptoms, B12, Folate, Homocysteine and kidney function.
What Does the Methylmalonic Acid (Serum) Test Check?
The test measures Serum Methylmalonic Acid, which can rise when Vitamin B12-dependent metabolism is impaired. This test measures 1 specialist biomarker.
Methylmalonic Acid - Serum
Measures circulating MMA, supporting assessment of functional Vitamin B12 deficiency when interpreted alongside kidney function and direct B12 measurement.
Who May Benefit From the Methylmalonic Acid (Serum) Test?
Serum MMA can be useful where direct Vitamin B12 results do not provide a clear answer.
People with borderline Vitamin B12 concentrations - MMA can provide additional functional evidence.
People with neurological symptoms and an inconclusive B12 result - Functional B12 deficiency can affect the nervous system.
People with macrocytosis of uncertain cause - B12 and Folate metabolism can be investigated.
People with gastrointestinal malabsorption - Coeliac disease, inflammatory bowel disease and gastric disorders can affect B12 absorption.
People following bariatric or gastric surgery - Anatomical changes can increase B12 deficiency risk.
People using Metformin long term - Metformin can contribute to lower Vitamin B12 in some patients.
People using long-term acid-suppressing medication - Reduced gastric acidity can affect dietary B12 absorption.
People with previous abnormal MMA - Repeat measurement can assess metabolic response to treatment.
How to Prepare
Do not stop prescribed Vitamin B12 treatment solely to increase MMA.
Kidney function is essential context when a Serum MMA result is elevated.
Symptoms and Reasons to Consider the Methylmalonic Acid (Serum) Test
Functional Vitamin B12 deficiency can produce neurological and haematological symptoms.
Numbness or tingling in the hands or feet - B12 deficiency can affect peripheral nerves.
Unexplained balance problems - Neurological involvement can occur with deficiency.
Macrocytosis - Enlarged red blood cells are a recognised finding.
Persistent fatigue with borderline B12 - Additional functional testing can help clarify status.
Glossitis or oral soreness - B12 deficiency can affect rapidly dividing mucosal cells.
Cognitive or neurological symptoms with nutritional risk - B12 status may warrant careful assessment.
Progressive neurological symptoms require timely medical assessment.
Treatment should not be delayed simply to obtain a pre-treatment MMA result when clinically significant Vitamin B12 deficiency is strongly suspected.
How to Book Your Methylmalonic Acid (Serum) Test
The Serum Methylmalonic Acid test can be booked privately for specialist assessment of Vitamin B12 metabolism.
Choose the Methylmalonic Acid (Serum)
Select the individual Serum MMA blood test online.
Select your sample collection option
Choose an in-clinic blood draw or professional home or hotel phlebotomy where suitable.
Attend your appointment
A trained healthcare professional collects the required venous blood sample.
Laboratory analysis
Your serum undergoes specialist measurement of Methylmalonic Acid - Serum.
Receive your results securely
Your authorised result is delivered securely and can be interpreted alongside Vitamin B12 and kidney-function markers.
When Will I Receive My Results?
The current specialist laboratory turnaround for Methylmalonic Acid - Serum is approximately 5 days after laboratory receipt.
The test requires specialist biochemical analysis.
The customer price currently listed by London Blood Tests is £268.
Understanding Your Results
A normal MMA result makes significant functional Vitamin B12 deficiency less likely.
A raised result can support impaired Vitamin B12-dependent metabolism.
The degree of elevation and clinical context matter.
Reduced kidney function can increase Serum MMA even when Vitamin B12 status is adequate.
Recent B12 supplementation or injections can lower MMA.
A raised MMA should therefore not automatically be interpreted as nutritional deficiency without considering eGFR and treatment history.
Homocysteine, direct Vitamin B12 measurement and the Full Blood Count can provide additional information.
Why Book With London Blood Tests?
London Blood Tests provides private Serum MMA testing for detailed assessment of Vitamin B12 metabolism.
Measures a sensitive functional marker - MMA can identify impaired B12-dependent metabolism.
Useful with borderline Vitamin B12 - Functional information can clarify an uncertain standard result.
Relevant to neurological symptoms - Vitamin B12 deficiency can affect the nervous system.
Can complement Homocysteine - The two metabolic markers provide different information.
Can complement kidney testing - Renal function is important when interpreting MMA.
Specialist laboratory analysis - Results are expected approximately 5 days after laboratory receipt.
Professional blood collection - Clinic and suitable home or hotel appointments are available.
Clear pricing - The Methylmalonic Acid (Serum) test costs £268.
Private Methylmalonic Acid (Serum) Blood Test in London
London Blood Tests provides private Serum Methylmalonic Acid testing for people requiring detailed assessment of functional Vitamin B12 status.
The test costs £268 and measures 1 specialist biochemical biomarker.
Results are expected approximately 5 days after laboratory receipt.
Kidney function and recent Vitamin B12 treatment should be considered when interpreting the result.