Description

A Methylmalonic Acid (MMA) test measures the amount of MMA in your blood. MMA is a compound that accumulates when your body lacks vitamin B12, making this test a sensitive marker for detecting vitamin B12 deficiency, even before anemia develops.

Purpose of the Test

  • Detect early vitamin B12 deficiency: Helps diagnose deficiency before neurological symptoms appear.
  • Differentiate causes of anemia: Useful when combined with other tests like homocysteine or B12 levels.
  • Monitor treatment: Tracks the effectiveness of vitamin B12 supplementation.

Clinical Significance

  • Elevated MMA: Indicates vitamin B12 deficiency, which can result from poor dietary intake, malabsorption (e.g., pernicious anemia, gastrointestinal disorders), or certain medications.
  • Normal MMA: Suggests adequate vitamin B12 function; high homocysteine with normal MMA may indicate folate deficiency instead.

Test Details

  • Sample: Blood (serum)
  • Preparation: Fasting not required
  • Interpretation: Results are compared to reference ranges, with high MMA levels prompting evaluation for vitamin B12 deficiency and possible neurological assessment.

This test is especially valuable for identifying subclinical B12 deficiency, which can prevent irreversible nerve damage if treated early.