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Methylmalonic Acidemia with Homocystinuria

What is methylmalonic acidemia with homocystinuria?

Methylmalonic acidemia with homocystinuria is a rare genetic disorder characterized by the body’s inability to properly breakdown and process certain amino acids, fats, and cholesterol for use. The symptoms of this disease usually appear during infancy but can appear at any age. It is estimated that methylmalonic acidemia with homocystinuria occurs in 1 in 200,000 births worldwide.

What are the symptoms of methylmalonic acidemia with homocystinuria?

The symptoms of methylmalonic acidemia with homocystinuria vary from individual to individual. Those that appear during infancy include:
  • Failure to grow or gain weight appropriately (failure to thrive)
  • Difficulty feeding
  • Weak muscle tone
  • Seizures
  • Abnormally small head (Microcephaly)
  • Developmental delays
  • Eye problems
  • Anemia
When methylmalonic acidemia with homocystinuria appears during adolescence or adulthood, symptoms include:
  • Psychiatric and behavioral problems
  • Hallucinations
  • Speech problems
  • Intellectual decline
  • Memory problems
  • Dementia
  • Extreme fatigue
  • Poor muscle and movement control
  • Difficulty walking
  • Numbness in legs
  • Weakness

What causes methylmalonic acidemia with homocystinuria?

Methylmalonic acidemia with homocystinuria is caused by an inherited defect in necessary enzymes needed for the proper breakdown and use of proteins and fats by the body. The defect of this enzyme leads to a buildup of harmful substances and toxins in the blood. This genetic defect must be passed by both the mother and father to their child.

Are there treatment options for methylmalonic acidemia with homocystinuria?

Treatment of methylmalonic acidemia with homocystinuria is directed at lessening the severity of symptoms and limiting damaging effects. Early intervention is vital to help avoid prolonged and serious health problems. Without treatment, methylmalonic acidemia with homocystinuria can be life-threatening. Treatment plans will vary from individual to individual and are usually developed with coordination between primary care doctors, metabolic doctors, and dieticians. Examples of treatment include:
  • Low protein, low fat, high carbohydrate diet
  • Frequent meals
  • Medically developed formulas for infants and foods for older individuals
  • Close monitoring and quick intervention during times of illness
  • Blood and urine tests
  • Hospitalization during times of prolonged illness and/or fatigue
  • Medications such as B12, L-carnitine, and Betaine

Where can I find more information about methylmalonic acidemia with homocystinuria?

Methylmalonic Acidemia with Homocystinuria Articles