Methylmalonic Acid Qualitative Urine Test is for metabolic disorders. The assay is a specific diagnostic marker for methylmalonic acidemias which can be congenital or acquired. The acquired causes are more common and usually found in patients with cobalamine (Vitamin B12) deficiency as a consequence of intestinal malabsorption, impaired digestion or poor diet. Other causes are renal insufficiency, hypovolemia and bacterial overgrowth in small intestine.