Methylmalonic Acid (Plasma)

Clinical Use: Increased levels support a diagnosis of Vitamin B12 deficiency.
Background: The concentration of plasma MMA is elevated primarily in patients affected with methylmalonicacidaemia and patients with a nutritional deficiency of Vitamin B12 and/or folate.Acquired causes of methylmalonic acidaemia are more common. Elevated MMA levels in plasma and urine are found in patients with cobalamin (Vitamin B12) deficiency as a consequence of intestinal malabsorption, impaired digestion, or poor diet. Other conditions such as renal insufficiency, hypovolemia, and bacterial overgrowth of the small intestine also contribute to the possible causes of mild methylmalonic acidemia and aciduria.

Elderly patients with cobalamin deficiency may present with peripheral neuropathy, ataxia, loss of position and vibration senses, memory impairment, depression, and dementia in the absence of anaemia.

Reference Ranges: 73 – 271 nmol/L
Associated Diseases:
Patient Preparation: None required
Specimen Requirements: EDTA plasma is required
Turnaround Time: 2 weeks
Additional Information: Increased levels support a diagnosis of Vitamin B12 deficiency.
Referred Test: Referred test
Location: Centre for Haemostasis and Thrombosis