Skip to Content

Homocystinuria

Topic Overview

Homocystinuria is a rare inherited disease that causes a deficiency of one of several enzymes needed for the breakdown of food (metabolism). This enzyme deficiency may cause a buildup of homocysteine in the blood. Excess homocysteine may be released in the urine.

Babies born with homocystinuria may fail to grow and gain weight (failure to thrive) and may experience developmental delays. People with homocystinuria may develop diseases of the heart and blood vessels at a young age. If homocystinuria is not diagnosed in infancy, other problems may develop, including:

  • Partial dislocation of the lens of the eyes (ectopia lentis).
  • Severe nearsightedness (myopia).
  • Progressive intellectual disability.
  • Seizures.
  • Psychiatric problems.
  • Skeletal problems (such as scoliosis, osteoporosis, or protrusion or depression of the breastbone).
  • Formation of blood clots in deep veins (deep venous thrombosis, or DVT).
  • Stroke.

People with homocystinuria may have a thin appearance, with long, slender arms, legs, fingers, and toes. These features have been described as "marfanoid" because of the similarity to Marfan's syndrome.

Treatment for homocystinuria may include eating foods low in certain amino acids and taking vitamin supplements and medicine to enhance the breakdown of homocysteine.

Related Information

References

Other Works Consulted

  • Rezvani I, Rosenblatt DS (2011). Methionine section of Defects in metabolism of amino acids. In RM Kliegman et al., eds., Nelson Textbook of Pediatrics, 19th ed., pp. 425–429. Philadelphia: Saunders.

Credits

By Healthwise Staff
Primary Medical Reviewer E. Gregory Thompson, MD - Internal Medicine
Specialist Medical Reviewer George Philippides, MD - Cardiology
Current as of March 12, 2014

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.

© 1995-2014 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.

Symptom Checker

Feeling under the weather?

Use our interactive symptom checker to evaluate your symptoms and determine appropriate action or treatment.

Decision Points

Our interactive Decision Points guide you through making key health decisions by combining medical information with your personal information.

You'll find Decision Points to help you answer questions about: