Causes
The main cause of methylmalonic acidemia (MMA) is a deficiency in methylmalonyl-CoA mutase, an enzyme involved in the metabolism of certain amino acids and fats.
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Mutations in genes responsible for the production of enzymes that process methylmalonic acid are inherited.
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Some forms of MMA are associated with vitamin B12 deficiencies, which are essential for the proper functioning of enzymes involved.
Symptoms
Symptoms of methylmalonic acidemia can vary in severity and present soon after birth or later in life.
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Infants may experience frequent vomiting and feeding difficulties.
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An overall feeling of drowsiness and lethargy.
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A developmental delay is a delay in reaching developmental milestones.
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Weakness and reduced muscle tone.
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Breathing problems: Difficulty breathing and rapid breathing.
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When untreated, metabolic acidosis can lead to lethargy, respiratory distress, and coma.
Diagnosis
There are several steps involved in diagnosing methylmalonic acidemia:
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MMA is often included in newborn screening programs, which test blood samples for elevated levels of methylmalonic acid.
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Methylmalonic acid levels in the blood and urine may indicate MMA.
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Testing for genetic mutations associated with MMA to confirm the diagnosis.
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Measuring the activity of methylmalonyl-CoA mutase in cultured fibroblasts or blood cells.
Treatment
Methylmalonic acidemia is treated by managing symptoms and preventing metabolic crises:
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A low-protein diet to reduce the intake of amino acids that cannot be properly processed. Special medical foods and formulas may be necessary.
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Some forms of MMA respond to vitamin B12 supplements.
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To help the body remove harmful substances, medications like carnitine may be prescribed.
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Metabolic crises require immediate medical attention, including intravenous fluids, glucose, and other treatments to correct metabolic imbalances.
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To improve metabolic function in severe cases, liver or kidney transplantation may be considered.
Prevention
Genetic counseling and early intervention are key to preventing methylmalonic acidemia:
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A genetic counselor can help parents with a family history of MMA understand their risk of having a child with the disorder.
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MMA can be detected before birth in families with a history of the disorder.
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Detection of newborn complications through newborn screening programs allows for prompt treatment and management.
Conclusion
Early diagnosis and treatment of methylmalonic acidemia are crucial to managing symptoms and preventing metabolic crises. It is a genetic disorder that affects the body's ability to process fats and proteins. To manage this condition effectively, ongoing medical care, dietary management, and genetic counseling are essential components.
