Argininemia: Description, Causes and Risk Factors:
Argininemia is one type of amino acid disorder. People with this condition have problems removing ammonia from the body. Ammonia is a harmful substance. It is made when protein and its building blocks, amino acids, are broken down for use by the body.
Argininemia affects an enzyme needed to break down certain proteins and remove waste ammonia from the body. A person with argininemia doesn’t have enough enzyme to break down protein and remove ammonia from the body. Ammonia is very harmful to the body and can cause health problems if not removed. Argininemia is a genetic disorder that is passed on (inherited) from parents to a child. The mother and father of an affected child carry a gene change that can cause argininemia. Parents usually do not have signs or symptoms, or even know they carry the gene change.
It occurs when an enzyme called “arginase” is either missing or not working properly. This enzyme’s job is to help break down the amino acid arginine and to help remove ammonia from the body. When arginase is not working, arginine, along with ammonia, can build up in the blood. This can cause serious effects on growth, learning and health.
Argininemia is inherited in an autosomal recessive manner. It affects both boys and girls equally. Everyone has a pair of genes that make the arginase enzyme. In children with this disease, neither of these genes works correctly. These children inherit one nonworking gene for the condition from each parent. Parents of children with argininemia rarely have the disorder. Instead, each parent has a single non-working gene for argininemia. They are called carriers. Carriers do not have the condition because the other gene of this pair is working correctly. When both parents are carriers, there is a 25% chance in each pregnancy for the child to have this disease. There is a 50% chance for the child to be a carrier, just like the parents. And, there is a 25% chance for the child to have two working genes.
About one in every 300,000 babies in the United States is born with this condition.
Symptoms:
Initial symptoms:
Poor appetite.
- Excess sleepiness or lack of energy.
- Irritability.
- Vomiting.
Next stage symptoms:
Muscle weakness.
- Decreased or increased muscle tone.
- Breathing problems.
- Problems staying warm.
- Seizures.
- Swelling of the brain.
- Hyperactivity.
- Behavior problems.
- Learning delays.
- Coma.
Diagnosis:
Genetic testing for argininemia is available. Genetic testing, also called DNA testing, looks for changes in the pair of genes that cause the condition. Ask your metabolic doctor or genetic counselor whether DNA testing is available to your family.DNA testing is not necessary to diagnose your child. However, it can be helpful for carrier testing or prenatal diagnosis, discussed below.
Special blood and urine tests can be done to confirm argininemia. Talk to your metabolic doctor if you have about this type of testing.
Treatment:
Argininemia can be treated. Treatment is lifelong and include:
- Low protein diet – a dietician will help you set up the best diet for your child.
- Special formula low in protein.
- Medications to help prevequestions nt high ammonia.
- Children with argininemia should see their regular doctor, a doctor who specializes in this disease, and a dietician. Prompt and careful treatment helps children with argininemia live the healthiest lives possible.
With prompt and lifelong treatment, children with this disease may be able to live healthy lives with typical growth and learning.
NOTE: The above information is educational purpose. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition.
DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.