General Condition Information
- 3 hydroxy 3 methylglutaryl CoA lyase deficiency
- 3 hydroxy 3 methylglutaryl-CoA lyase deficiency
- 3-hydroxy 3-methyglutaric aciduria
- 3-hydroxy-3-methyglutaric aciduria
- 3-hydroxy-3-methylglutaric aciduria
- 3-hydroxy-3-methylglutaric aciduria (3-hydrox 3-methylglutaryl-CoA lyase)
- 3-hydroxy-3-methylglutaryl CoA lyase deficiency
- 3-hydroxy-3-methylglutaryl-CoA (HMG CoA) lyase deficiency
- 3-hydroxy-3-methylglutaryl-CoA lyase aciduria
- 3-hydroxy-3-methylglutaryl-CoA reductase deficiency
- 3-methyl-3-OH-glutaryl coA lyase deficiency
- 3-OH 3-CH glutaric aciduria
- 3-OH 3-CH3 glutaric aciduria
- Hydroxy 3 methylglutaric-CoA lyase
- Hydroxymethylglutaric aciduria
- Hydroxymethylglutaric aciduria, HMG-CoA lyase deficiency, or 3-OH 3-CH3 glutaric aciduria
- Hydroxymethylglutaric aciduria/HMG-CoA lyase deficiency
- Methylglutaric aciduria
- The number of babies born each year with this very rare condition is currently unknown.
- Most people with this condition are from Saudi Arabia, Portugal, or Spain
What is 3-hydroxy-3-methylglutaryl-CoA lyase deficiency
“HMG-CoA lyase” is the name of an enzyme in your body that helps you digest a part of some proteins called leucine. This enzyme breaks leucine into smaller pieces that your body can either use or remove. It also helps you break down fats into ketones, which your body uses to store energy.
If your baby’s HMG-CoA lyase enzyme does not work well, their body has trouble breaking down leucine and making energy. Waste (including toxins) can build up, and parts of your baby’s body might not make enough energy to work properly. Both of these things can damage your baby’s body.
Newborn Screening and Follow-Up
Newborn screening for HMG-CoA lyase deficiency is done using a small amount of blood collected from your baby’s heel. To learn more about this process, visit the Blood Spot Screening page.
During screening, a special machine measures how much of certain substances (called acylcarnitines) are in your baby’s blood. The body makes these substances when it breaks down food. Babies with high levels of these substances might have HMG-CoA lyase deficiency.
If your baby’s blood spot screening result for HMG-CoA lyase deficiency is out-of-range, your baby’s health care provider will contact you. Together, you will discuss next steps and follow-up plans.
An out-of-range screening result does not mean that your baby definitely has the condition. It does mean that your baby needs more follow-up testing. An out-of-range result can mean that your baby has one of several possible conditions. It is important to do follow-up testing to correctly identify the condition causing your baby’s result. To learn more about screening results, visit the Blood Spot Screening Results page.
Your baby may need the following tests after an out-of-range screening result:
- Blood and/or urine tests
- Genetic testing using a blood sample
You should complete any recommended follow-up testing as soon as possible. Babies with this condition can have serious health problems if they are not diagnosed and treated quickly.
False-positive newborn screening results for this condition may happen. Screening samples collected too early (before your baby is 24 hours old) may affect the results of screening.
Some babies may have a false-positive result for HMG-CoA lyase deficiency because their mother has high acylcarnitine levels. These babies do not have and will not develop HMG-CoA lyase deficiency. More testing on both mom and baby will determine who has high acylcarnitine levels.
Newborn screening helps babies lead healthier lives. If your baby has an out-of-range result, follow up with your health care provider quickly. It is important to follow their instructions. Your baby may need to get treatment right away, even if they are not showing signs or symptoms. In some cases, your baby’s health care provider may decide it is best to watch (monitor) your baby to decide next steps. Careful monitoring and early treatment will help your baby stay as healthy as possible.
Signs of HMG-CoA lyase deficiency vary widely. They often appear within the first few days or months of life. They may also appear later in childhood.
Signs of the condition may include the following:
The condition is caused by a change in the HMGCL gene. This gene gives your body instructions for making HMG-CoA lyase. HMG-CoA lyase is an enzyme that helps you digest proteins and fats from food.
Without a working HMGCL gene, your baby’s body cannot make enough normal copies of HMG-CoA lyase to properly break down leucine (from proteins) and make energy (from fats). As a result, your baby’s body gets damaged.
- HMG-CoA lyase deficiency is an autosomal recessive condition. Babies inherit the condition when each parent passes down a nonworking HMGCL gene to their baby. Only babies with two nonworking HMGCL genes—one from the mom and one from the dad—have this condition.
- People with one working copy and one nonworking copy of the HMGCL gene are called carriers.
- Carriers do not have or develop the condition. However, they may pass down a nonworking copy of the gene to their children.
- If two parents are carriers of a nonworking copy of the HMGCL gene, they have a 1 in 4 chance of having a child with HMG-CoA lyase deficiency.
- Carriers for HMG-CoA lyase deficiency often do not know they are carriers before having a child with the condition. In most cases, families have no history of the condition until the birth of a child with HMG-CoA lyase deficiency.
- Parents who already have a child with HMG-CoA lyase deficiency still have a 1 in 4 chance of having another child with HMG-CoA lyase deficiency. This 1 in 4 chance stays the same for all future children.
- Genetic counselors and medical geneticists can help families learn about this condition and the chance of having children with it. Visit the National Society of Genetic Counselors to find a genetic counselor and the American College of Medical Genetics and Genomics to find a medical geneticist.
Treatment and Management
It is important to talk to your health care provider about which treatment(s) are best for your baby. The goal of treatment is to prevent the health problems caused by this condition.
Treatments may include the following:
- Frequent feedings to avoid long periods without food
- Following strict emergency guidelines when sick
- L-carnitine supplements
- Special diet in some cases
Children who receive early and ongoing treatment for HMG-CoA lyase deficiency can have healthy growth and development.