Methylmalonic acidemia
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:
Overview
Methylmalonic acidemia (MMA, also known as “methylmalonic aciduria”) is an inborn error of intermediary metabolism that may present in the early neonatal period with progressive encephalopathy and death due to a secondary hyperammonemia.
Methylmalonic acidemia does not always result in death, if it is diagnosed at an early age.
Historical Perspective
Classification
Types
- Online Mendelian Inheritance in Man (OMIM) 251100 – cblA type
- Online Mendelian Inheritance in Man (OMIM) 251110 – cblB type
- Online Mendelian Inheritance in Man (OMIM) 277400 – cblC type
- Online Mendelian Inheritance in Man (OMIM) 277410 – cblD type
- Online Mendelian Inheritance in Man (OMIM) 277380 – cblF type
- Online Mendelian Inheritance in Man (OMIM) 606169 – cblH type
- Online Mendelian Inheritance in Man (OMIM) 251000 – mut type
Cobalmin (vitamin B12) is also needed for the conversion of methylmalonyl-CoA to Succinyl-CoA. Mutations leading to defects in cobalmin or in its transport frequently result in the development of acidemia. The numerous pat
Pathophysiology
Causes
Methylmalonic acidemia is an inherited disorder in which the body is unable to process certain proteins and fats (lipids) properly. Methylmalonic acidemia is a disorder of amino acid metabolism, involving a defect in the conversion of methylmalonyl-coenzyme A (CoA) to succinyl-CoA by methylmalonyl-CoA mutase.
Differentiating Methylmalonic acidemia from Other Diseases
Epidemiology and Demographics
Risk Factors
Screening
Natural History, Complications, and Prognosis
Diagnosis
Diagnostic Criteria
History and Symptoms
Physical Examination
Laboratory Findings
Imaging Findings
Other Diagnostic Studies
Treatment
Medical Therapy
Surgery
Prevention
See also
References
- Organic Acidemia Association
- Methylmalonic acidemia at NLM Genetics Home Reference
- Washington Health Center
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