2,4-Dienoyl-CoA reductase deficiency (DE-RED) is an inherited (genetic) condition that prevents your baby’s body from breaking down certain fats and turning them into energy. If your baby does not make enough energy from fat, substances build up in the blood and can cause serious health problems. There have only been three reported cases of DE-RED.

The condition is thought to be caused by a change in the NADK2 genes. This gene gives the body instructions for making an enzyme that breaks down a certain type of fat, called “unsaturated fatty acids.”

When a change in the NADK2 gene causes it to not work, the body cannot properly break down fat to make energy. This leads to the signs and symptoms of the condition.

DE-RED is a genetic condition. Babies inherit it from their biological (birth) parents.

• DE-RED is thought to be an autosomal recessive condition. Babies inherit the condition when each parent passes down a nonworking NADK2 gene to their baby. Only babies with two nonworking NADK2 genes—one from the mom and one from the dad—have this condition.
  • People with one working copy and one nonworking copy of the NADK2 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 NADK2 gene, they have a 1 in 4 chance of having a child with DE-RED.
  • Carriers for DE-RED 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 DE-RED.
  • Parents who already have a child with DE-RED still have a 1 in 4 chance of having another child with DE-RED. 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.

There have only been three reported cases of DE-RED. In these cases, signs of the condition were present from birth.

Signs of the condition in the three known cases have included the following:

• Poor feeding
• Small head size (microcephaly)
• Weak muscle tone (hypotonia)
• Vomiting
• Gets upset easily
• Delays in weight gain
• Breathing problems
• Seizures
• Abnormal, involuntary eye movements (nystagmus)

Newborn screening for DE-RED is done using a small amount of blood collected from your baby’s heel. 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 DE-RED.

What Happens After an Out-of-Range Screening Result?

If your baby’s blood spot screening result for DE-RED 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.

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. This condition can cause serious health problems soon after birth.

There have only been three reported cases of this condition, so there is little information on false-positive newborn screening results. 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

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.

Because there have been only been two known cases of DE-RED, doctors are still learning how best to treat this condition. In the two cases, the children received the following treatments to try to prevent their health problems:

• Formula low in an amino acid called lysine
• Carnitine supplements