methylmalonic acidemia

pathology

Also known as: MMA

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Last updated

July 16, 2026

Quick Summary

Methylmalonic acidemia (MMA) is an organic acidemia, a group of inherited metabolic disorders characterized by the accumulation of organic acids in the body due to blocked metabolic pathways involving specific enzymes. In MMA, this blockage is due to a defect in the enzyme methylmalonyl-CoA mutase.1

This condition can lead to symptoms similar to propionic acidemia, including potential kidney failure. Some forms of MMA respond to vitamin B12 treatment, while rarer forms, caused by issues with vitamin B12 processing, may appear later in childhood with neurological problems. MMA is an autosomal recessive condition, meaning it is inherited from both parents.12

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metabolic disease
Organic acidemias
…with the classic form of methylmalonic acidemia (MMA), caused by a defect in the enzyme methylmalonyl-CoA mutase, have symptoms similar to individuals with propionic acidemia but may also develop the long-term complication of kidney failure. A combined liver-kidney transplant may be beneficial in some patients with severe kidney disease. One…
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…with the classic form of methylmalonic acidemia (MMA), caused by a defect in the enzyme methylmalonyl-CoA mutase, have symptoms similar to individuals with propionic acidemia but may also develop the long-term complication of kidney failure. A combined liver-kidney transplant may be beneficial in some patients with severe kidney disease. One…
Read More