What is homocystinuria?
Homocystinuria is a rare inherited metabolic condition that affects how the body processes certain proteins. People with this condition can’t break down the chemical homocysteine, which builds up in the blood and urine over time.
This build up can affect several parts of the body, including the eyes, bones, brain and blood vessels. Symptoms often begin in childhood, but the condition can look different from person to person.
Although homocystinuria is lifelong, early diagnosis and treatment can help a child live life well.
What causes homocystinuria?
Homocystinuria is caused by a build up of homocysteine. This happens because of a changed gene that doesn’t carry the right instructions to make the enzyme needed to help break it down. When the enzyme doesn’t work fully, homocysteine stays in the body instead of being cleared.
The condition is inherited and the genetic change will be present from birth. Family members can carry the gene without having symptoms themselves.
Treatments help to manage homocysteine levels, keeping the body in balance.
What are the symptoms of homocystinuria?
The symptoms of homocystinuria usually begin in childhood and may include:
- Vision problems – including lens dislocation or severe short-sightedness
- Tall, thin build – with long limbs and fingers.
- Fragile bones – bones may break more easily
- Developmental delays – including learning difficulties
- Behavioural or emotional changes – such as anxiety or mood changes
- Blood clotting problems – which can become serious if untreated
Symptoms usually develop slowly and can be difficult to spot, so recognising these changes can help doctors start the right treatment as soon as possible.
