General Condition Information
- Carnitine palmitoyl transferase deficiency type 2
- Carnitine palmitoyl transferase deficiency type II
- Carnitine palmitoyl transferase deficiency, type II
- Carnitine palmitoyl transferase II deficiency
- Carnitine palmitoyl transferase type II deficiency
- Carnitine palmitoyltransferase 2 deficiency
- Carnitine palmitoyltransferase deficiency II
- Carnitine palmitoyltransferase deficiency type 2
- Carnitine palmitoyltransferase deficiency, type 2
- Carnitine palmitoyltransferase type 2
- Carnitine palmitoyltransferase type II
- Carnitine palmitoyltransferase type II deficiency
- Carnitine palmitoyltransferase, type II
- Carnitinepalmitoyl transferase deficiency type II
- CPT2 deficiency
- It is unknown how many babies are born with this rare condition each year in the United States.
- Visit GeneReviews to learn more about how often this condition occurs.
What is Carnitine palmitoyltransferase II deficiency
There are three different types of CPT II deficiency based on when signs of the condition appear:
- Newborn: Appears at birth.
- Infant: Appears within the first year of life.
- Myopathic: Appears later in life. This milder myopathic type is the most common type of CPT II deficiency.
“Carnitine palmitoyltransferase 2” is an enzyme that helps break down fats called “long chain fatty acids” so cells can process them properly.
If your baby does not have enough of this enzyme, their body has trouble using fats for energy. This condition can be more or less severe depending on how much of the enzyme your baby’s body can make.
Breaking down fat for energy allows your body to work properly. It is especially important after a long time without food (fasting) and during illness. If your body does not make enough energy from fat, blood sugar levels can become dangerously low.
When fats are not processed, waste builds up, including toxins. These toxins can damage your liver, heart, and muscles. If untreated, the lack of energy and increased toxins lead to the signs and symptoms of the condition.
Newborn Screening and Follow-Up
Newborn screening for CPT II 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 produces these substances when it makes energy from fats. Babies with high levels of these substances might have CPT II deficiency.
If your baby’s blood spot screening result for CPT II 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. 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
- Small skin sample
You should complete any recommended follow-up testing as soon as possible. Babies with this condition can have serious health problems soon after birth if they are not diagnosed and treated quickly.
False-positive newborn screening results for this condition are rare. However, some situations can affect screening results:
- Screening samples were collected too early (before the baby is 24 hours old)
- Babies who were given carnitine may have false positive results for this condition.
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 the condition appear at different times depending on the type of CPT II deficiency. The newborn type shows signs soon after birth. The infant type shows signs within the first year of life. The milder myopathic type doesn’t begin showing signs until early in childhood or in adulthood.
Symptoms of CPT II deficiency can be triggered by common illnesses (like a cold or flu) or a long time without food.
Signs of CPT II deficiency in babies who have the newborn or infant forms of CPT II deficiency may include the following:
The condition is caused by a change in the CPT2 gene. This gene gives the body instructions for making “carnitine palmitoyltransferase 2.” Carnitine palmitoyltransferase 2 is an enzyme that helps in the process of breaking down a certain type of fat, called “long-chain fatty acids.” Long-chain fatty acids are important sources of energy for the heart and muscles.
When a change in the CPT2 gene causes it not to work properly, your baby cannot make enough normal copies of carnitine palmitoyltransferase 2. As a result, your baby cannot properly break down fats to make energy and get rid of toxins.
- CPT II deficiency is an autosomal recessive condition. Babies inherit the condition when each parent passes down a nonworking CPT2 gene to their baby. Only babies with two nonworking CPT2 genes—one from the mom and one from the dad—have this condition.
- People with one working copy and one nonworking copy of the CPT2 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 CPT2 gene, they have a 1 in 4 chance of having a child with CPT II deficiency.
- Carriers for CPT II 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 CPT II deficiency.
- Parents who already have a child with CPT II deficiency still have a 1 in 4 chance of having another child with CPT II 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:
- Regular and frequent meals and snacks
- Diet high in carbohydrates and low in fat
- Medium chain triglyceride (MCT) oil supplements to provide fats the body can break down
- L-carnitine supplements to help the body break down fats (in some cases)
- Avoiding cold weather (in some cases)
Children who receive early and ongoing treatment for CPT II deficiency can have healthy growth and development. Some children will develop issues with their heart, lungs, or liver even with treatment.