Disorders on the Newborn Blood Screening Panel

The following sections describe the disorders tested through newborn screening. A more in-depth description of each disorder can be found in the NBS Test Panel of Diseases in the Health Professionals section. If you have additional questions about these disorders, please ask your doctor.

Argininosuccinic Acidemia (ASA)

Babies with ASA cannot properly digest the protein in foods, causing ammonia to build up in the blood. If not treated, babies lose appetite, start vomiting, become listless, and often have seizures. A baby with ASA is given a special dietary formula and needs to receive regular medical care. Further special testing is needed to determine if a baby has ASA.

Biotinidase Deficiency

Babies with this problem do not have enough of the vitamin called biotin. Without this vitamin, the baby’s growth and development will not be normal. A baby with biotinidase deficiency needs a medicine containing biotin and regular medical care.

Related Link: Biotinidase Deficiency (eMedicine)

Citrullinemia (Types I & II)

Babies with citrullinemia can not properly digest the protein in foods, causing ammonia to build up in the blood. If not treated, babies lose appetite, start vomiting, become listless, and often have seizures. A baby with citrullinemia is given a special dietary formula and needs to receive regular medical care. Further special testing is needed to determine if a baby has citrullinemia.

Congenital Adrenal Hyperplasia (CAH)

Most babies with this problem do not have enough of the chemical 21-hydroxylase. Without 21-hydroxylase, a baby’s growth and development will not be normal. A baby with CAH is given medicine called hydrocortisone and needs regular medical care.

Congenital Hypothyroidism

A baby born with this problem does not make enough thyroid hormone. Thyroid hormone keeps a baby’s body growing strong and healthy. Without it, poor physical and mental development can occur. This problem is treated with a daily medicine to replace the hormone and regular medical care.

Cystic Fibrosis (CF)

Cystic fibrosis causes thick mucus to collect in the lungs which can lead to lung infections. In most people with cystic fibrosis, there is also difficulty in absorbing fat and protein. The lung and digestive problems are both treatable, and a baby with CF will need regular medical care and a good diet.

Related Link: Cystic Fibrosis Foundation

Fatty Acid Oxidation Disorders

Babies with one of these disorders have trouble burning fat for energy. This can lead to vomiting, low blood sugar or more serious problems such as coma. Treatment depends on the disorder a baby has but may include a special diet and medication. A baby with a fatty acid oxidation disorder must have regular medical care. The newborn screen tests for these 12 fatty acid oxidation disorders:

Medium Chain Acyl-CoA Dehydrogenase Deficiency (MCAD)
Long Chain 3-Hydroxyacyl CoA Dehydrogenase Deficiency (LCHAD)
Very Long Chain Acyl-CoA Dehydrogenase Deficiency (VLCAD)
Carnitine Palmitoyl Transferase Deficiency Type IA (CPT-IA)
Carnitine Palmitoyl Transferase Deficiency Type II (CPT-II)
Glutaryl CoA Dehydrogenase Deficiency Type II aka Glutaric Acidemia Type II (GA-II)
2,4-Dienoyl-CoA Reductase Deficiency (DE RED)
Trifunctional Protein Deficiency (TFP)
Carnitine/Acylcarnitine Translocase Deficiency (CACT)
Carnitine Uptake Defect (CUD)
Medium/Short Chain Hydroxyacyl-CoA Dehydrogenase Deficiency (M/SCHAD)
Medium Chain 3-Ketoacyl-CoA Thiolase Deficiency (MCKAT)

Galactosemia

A baby with this problem cannot digest the sugar galactose. If not treated, galactose will build up in the body causing damage to the eyes, liver and brain. Babies with galactosemia must not have foods containing galactose or lactose, including breast milk and some infant formulas. Treatment includes a special diet and regular medical care.

Homocystinuria

Babies with HCU are unable to digest a part of food called methionine. If not treated, HCU can lead to seizures, developmental delay, eye problems, mental retardation or failure to thrive. A baby with HCU is given a special formula with special vitamins and needs to receive regular medical care.

Hypermethioninemia

Babies with hypermethioninemia have slightly elevated methionine levels on newborn screening and subsequent blood tests. Dietary treatment may or may not be required depending upon the methionine level. These babies require ongoing blood tests to determine if dietary treatment will be necessary.

Hyperphenylalaninemia (PKU)

Babies with PKU have slightly elevated phenylalanine levels on newborn screening and subsequent blood tests. Dietary treatment may or may not be required depending upon the phenylalanine level. These babies require ongoing blood tests to determine if dietary treatment will be necessary.

Maple Syrup Urine Disease (MSUD)

Babies with MSUD are unable to digest leucine, isoleucine and valine. Leucine, isoleucine and valine are found in foods with protein. If not treated, MSUD can lead to poor feeding, vomiting, muscle weakness, and brain damage. A baby with MSUD is given a special formula and needs to receive regular medical care.

Mucopolysaccharidosis Type I (MPS I)

Mucopolysaccharidosis type I (MPS I) is one of a group of inherited (genetic) conditions that prevent the body from processing sugars properly.

Our body uses complicated sugars called glycosaminoglycans (GAGs) in several important processes. An enzyme called alpha-L-iduronidase (IDUA) breaks down GAGs so that the body can use them. This process occurs in special compartments inside your cells called lysosomes.

MPS I is a condition that occurs when IDUA is absent or present at low levels. The lysosomes then have trouble breaking down GAGs. This causes a buildup of GAGs in the tissues that can result in problems throughout the body. GAGs used to be called mucopolysaccharides, which is where the condition got its name.

There are two types of MPS I – severe and attenuated – that differ in signs, symptoms, and age of onset. The severity of the condition depends on how much IDUA activity is present. IDUA activity shows how well your baby can break down GAGs. High levels of GAGs can damage many parts of the body.

https://newbornscreening.hrsa.gov/conditions/mucopolysaccharidosis-type-i#condition-details

Organic Acidemias

Babies with one of these disorders cannot remove certain waste products from their blood. This can lead to vomiting, low blood sugar or more serious problems such as coma. Treatment depends on which disorder a baby has but may include a special diet and medication. A baby with an organic acidemia must have regular medical care. The newborn screen tests for these 12 organic acidemias:

Propionyl CoA Carboxylase Deficiency aka Propionic Acidemia (PA)
Glutaryl CoA Dehydrogenase Deficiency Type I aka Glutaric Acidemia Type I (GA-I)
Methylmalonic Acidemia (MMA) Mutase
Methylmalonic Acidemia (MMA) Cbl A and B
Methylmalonic Acidemia (MMA) Cbl C and D
Isovaleryl CoA Dehydrogenase Deficiency aka Isovaleric Acidemia (IVA)
3-Methylcrotonyl-CoA Carboxylase Deficiency (3-MCC)
Mitochondrial Acetoacetyl-CoA Thiolase Deficiency (ß -KetoThiolase)
3-Hydroxy-3-Methylglutaryl-CoA Lyase Deficiency (HMG)
Multiple CoA Carboxylase Deficiency (MCD)
2-Methyl-3-Hydroxybutyryl CoA Dehydrogenase Deficiency (2M3HBA)
3-Methylgutaconyl CoA Hydratase Deficiency (3MGA)

Related Link: Organic Acidemia Association

Phenylketonuria (PKU)

(Includes Biopterin Cofactor defects of regeneration and biosynthesis)

Babies with PKU do not have the chemical needed to digest phenylalanine. Phenylalanine is found in foods with protein. If not treated, PKU can lead to brain damage and learning problems. A baby with PKU is given a special formula and needs to receive regular medical care.

Related Link: PKU News

Pompe Disease

Pompe disease is an autosomal recessive disorder caused by a lack of function of the enzyme acid alpha-1, 4-glugosidase (GAA) or acid maltase. Pompe disease is also a lysosomal storage disorder. Without the proper function of GAA, glycogen that enters into the lysosome is not broken down, but continues to build up and disrupt the function of the lysosome. Since there is no (or little) enzyme to break down the glycogen, muscles accumulate large deposits of glycogen. The large deposits of glycogen cause lysosomes to grow larger until they will eventually breakdown and disrupt the function of the cell and the organs that the cell makes up-including the heart and skeletal muscles.

Severe Combined Immune Deficiency (SCID)

This is a group of inherited diseases that result in a lack of T-cells and severely reduced B-cell function. Babies with SCID are extremely susceptible to infection and die early in life unless treated with bone marrow transplantation.

Sickle Cell Disease, Hemoglobin S/C Disease, Hemoglobin S-Beta Thalassemia, Hemoglobin E-Beta Thalassemia

Healthy red blood cells are shaped like a donut. With sickle cell disease, some red blood cells are sickle shaped, like a banana. These cells can become trapped in blood vessels causing pain, discomfort, or damage. Babies with sickle cell disease are more likely to develop severe infections.

Treatment includes medications to lower this risk of infection, such as penicillin and special vaccines. If needed, treatment may also include medications for pain. Babies with sickle cell diseases also need regular medical care.

Trait and Variant Hemoglobins

The newborn screen for sickle cell diseases identifies those babies with hemoglobin traits (carriers) or other changes in red blood cells (variant hemoglobins). Babies with hemoglobin traits or variant hemoglobins for the most part require no treatment. Genetic counseling for the parents is recommended to determine the risk of having a future baby that may need treatment.

Related Links:

Spinal Muscular Atrophy (SMA)

SMA affects the nerves in the spinal cord that send signals to the muscles to tell them what to do. When these nerves are defective, muscles don’t know how to do their job and become very weak. People with SMA may have difficulty walking, eating, and breathing because of muscle weakness.

X-Linked Adrenoleukodystrophy (X-ALD)

X-linked adrenoleukodystrophy (X-ALD) is an inherited (genetic) condition that prevents the body from breaking down certain fats that are important in certain parts of the body like the brain, spinal cord, as well as the adrenal glands, which help produce certain hormones in the body.

The X-linked adrenoleukodystrophy protein (ALDP) is a transporter protein that brings a type of fat called very long-chain fatty acids (VLCFA) into peroxisomes to be processed. Peroxisomes are small areas inside your cells that perform important functions, including breaking down this type of fat.

In X-ALD, the protein ALDP is not made correctly, so these fats cannot enter peroxisomes to be processed. These VLCFA build up over time and damage the nervous system (including the brain and spinal cord) and the adrenal glands, which produce important hormones.

Damage caused by the buildup of VLCFA in the adrenal glands can prevent the adrenals from producing necessary hormones. This can make it harder to recover from infections or other stress. This damage, called adrenal insufficiency, is not ordinarily seen in babies but may develop as they get older. Adrenal insufficiency can be found with a blood test.

The VLCFA can also build up in the brain. About 35 percent of boys with this buildup develop the brain, or cerebral, form of X-ALD, which is the most severe. This condition usually occurs in boys 4 to 10 years old but can be earlier or later in life. There is also an adult form of the condition that affects the spinal cord, called adrenomyeloneuropathy (AMN). AMN is generally seen in young adults.

https://newbornscreening.hrsa.gov/conditions/x-linked-adrenoleukodystrophy

Newborn Point-of-Care Screening