What is Glutaric Aciduria Type 1 (GA1)?
Glutaric aciduria type 1(GA1), pronounced glue-ta-ric acid-ur-ee-a, is a rare but treatable inherited disorder that prevents the normal breakdown of protein.
Babies with GA1 inherit two faulty copies of the gene for GA1, one from each parent.
When we eat, our body breaks down protein in food into smaller parts called amino acids. Special chemicals found naturally in our body, called enzymes, then make changes to the amino acids so our body can use them.
Babies with GA1 have problems breaking down three amino acids called lysine, hydroxylysine and tryptophan because an enzyme is missing. This causes harmful substances to build up in their blood and urine.
Babies with GA1 benefit significantly from early treatment and can live healthy and active lives.
Without early diagnosis and treatment they can develop serious illness and damage to the brain.
Symptoms of GA1
Babies with GA1 are at risk of developing the following symptoms:
- poor feeding
- sleepiness
- floppiness
- abnormal movements
- vomiting
- breathing difficulties and fast breathing
- coldness
These symptoms can be controlled with treatment. Left untreated, GA1 can cause long-term damage to the brain, affecting muscle movement and the ability to sit, walk, talk or swallow.
When babies with GA1 become ill, they might show symptoms of metabolic crisis. A metabolic crisis is a period of time when the effects of the condition make your child seriously ill.
Some children with GA1 have been known to bleed around their brain (subdural haemorrhage). In rare cases they can develop bleeds in the back of the eyes (retinal haemorrhages).
Treatment
Treatment for GA1 involves a special low protein diet and medication.
Diet
The aim of the diet is to reduce the build-up of toxins. These toxins – glutaric acid and 3 hydroxyglutaric acid, formed from lysine, hydroxylysine and tryptophan – can cause metabolic crisis and brain injury. However, babies need a small amount of these amino acids to grow and develop. Your specialist metabolic dietitian will teach you how to measure and control the amount of protein you give to your baby, including breast milk feeds.
High protein foods and milk, including breast milk and normal infant formula, have to be limited. A special infant formula, which does not contain lysine and is low in tryptophan, is given to meet all nutritional needs.
This special infant formula is very important. It allows normal growth and development and helps reduce the build-up of the harmful toxins in the brain.
Medication
L-Carnitine helps clear some of the body’s toxins. It is taken by mouth and obtained on prescription through your doctor. It should be taken regularly even when your baby is ill.