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Citrullinemia

What is Citrullinemia?

Every baby born in Texas gets two newborn screening blood tests that check for a number of rare disorders, including

The first test is done 24 to 48 hours after birth. The second one is done at the baby’s checkup at one to two weeks of age. Finding and treating these disorders early can prevent serious complications such as growth and developmental delays, deafness, blindness, intellectual disabilities, seizures, and sudden or early death.

The lists below describe the core and secondary conditions for which babies in Texas are tested and include fact sheets for each condition that can be shared with parents or non-health professionals. Secondary conditions are believed to be clinically significant, but some may have an unclear natural history or lack appropriate medical therapy that affects long-term outcome. They are detected during screening for core conditions. Some secondary conditions may be as severe and life threatening as core conditions. Learn more about the newborn screening tests.

In addition to the blood spot tests, newborns also receive the following two point-of-service screenings at the birthing facility:

Amino Acid Disorders

Amino acid disorders are rare health conditions that affect a body’s metabolism which is how the body changes food into the energy it needs to have normal physical and mental development. People who have an amino acid disorder cannot make or break down certain proteins. Treatment may include a low-protein diet and/or special medical foods and formula and medication.

Core Conditions

Argininosuccinic Acidemia (ASA) is a condition that causes dangerous amounts of ammonia to build up in the body. People with this condition cannot remove the waste product ammonia produced when the body breaks down amino acids. High ammonia in the body can cause muscle weakness, brain swelling, and coma that can lead to death if not treated. Fact Sheets: ASA English - ASA Spanish

Citrullinemia (CIT) is a condition that causes dangerous amounts of ammonia to build up in the body. It happens when an enzyme called “argininosuccinic acid synthetase” (ASAS) is either missing or doesn’t work right. ASAS helps break down amino acids and removes ammonia from the body. Too much ammonia can cause muscle weakness, breathing problems, seizures, brain damage, and death if untreated. Fact Sheets: CIT English - CIT Spanish 

Homocystinuria (HCY) is a condition in which the body is not able to break down certain proteins. Amino acids build up in the body and can cause serious health problems. If not treated, this condition can cause intellectual disability and growth delays. It also can affect the eyes, bones, heart, and blood vessels. Treatment may involve a special restricted protein diet and supplemental medicines. Fact Sheets: HCY English -  HCY Spanish

Maple Syrup Urine Disease (MSUD) is a condition in which the body cannot break down certain amino acids from protein in food. It is named for the sweet maple syrup smell of the urine in untreated babies. Early detection and treatment can prevent severe intellectual disability, blindness and death. There is an increased risk in Mennonites. Fact Sheets: MSUD English - MSUD Spanish

Phenylketonuria (PKU) is a condition in which the body cannot break down an amino acid called phenylalanine (Phe) from the protein in food. This amino acid is needed for brain development. Undetected and untreated with a special restricted protein diet, PKU leads to intellectual disability. Persons of European descent are at increased risk. Fact Sheets: PKU English - PKU Spanish

Tyrosinemia Type I (TYR 1) is a condition caused by a deficiency in the liver of one enzyme that breaks down tyrosine. If not treated, the condition causes severe liver disease and other serious health problems. Treatment consists of medication including vitamin D and nitisinone, and a special restricted protein diet. Fact Sheets: TYR 1 English - TYR 1 Spanish 

Secondary Conditions

 

Argininemia (ARG) is a condition that causes harmful amounts of ammonia and the amino acid arginine to build up in the body. If untreated, ARG can cause muscle problems and developmental delay. Fact Sheets: ARG English - ARG Spanish

Benign Hyperphenylalaninemia (H-PHE) is a mild form of phenylketonuria. People with H-PHE have problems breaking down an amino acid, a building block of proteins, known as phenylalanine (PKU). Most people with this condition experience mild symptoms or no symptoms. They can have healthy growth and development. However, some babies with H-PHE do have a small risk of brain damage without treatment. Fact Sheet: H-PHE English

Biopterin Defect in Cofactor Biosynthesis (BIOPT-BS) is a condition that causes high amounts of phenylalanine and other harmful substances to build up in the body. People with BIOPT-BS are unable to break down certain amino acids including phenylalanine. If not treated, a baby can have developmental delays, seizures, behavior troubles and weak muscle tone. Fact Sheet: BIOPT-BS English

Biopterin Defect in Cofactor Regeneration (BIOPT-REG) is a condition that causes high amounts of phenylalanine and other harmful substances to build up in the body. People with BIOPT-BS are unable to break down certain amino acids including phenylalanine. If not treated, a baby can have developmental delays, seizures, behavior troubles and weak muscle tone. Fact Sheet: BIOPT-REG English

Citrullinemia, Type II (CIT II) is a condition in which the body is unable to make citrin, a protein that helps move substances within the cells. When citrin does not work properly, the body cannot break down carbohydrates correctly. It causes low sugar levels, high amino acid levels, and high amounts of ammonia in the blood. Fact Sheets: CIT II English - CIT II Spanish

Hypermethioninemia (MET) is a condition that occurs when there is a high amount of methionine in the body. People with MET are unable to break down an amino acid, a building block of proteins, known as methionine. If not treated, MET can cause learning delays, muscle weakness, and other health issues. Fact Sheet: MET English

Tyrosinemia, Type II (TYR II) is a condition in which the body is not able to break down an amino acid known as tyrosine. Signs of TYR II usually begin in the first year of life. These signs include sensitivity to light, eye redness, skin lesions on the hands and feet, behavior changes, and poor coordination. Early treatment can reduce the risk of developing intellectual disabilities. Fact Sheet: TYR II English

Tyrosinemia, Type III (TYR III) is a condition in which the body is not able to break down the amino acid tyrosine. Signs of TYR III may include poor coordination and balance and seizures. Early treatment can reduce the risk of developing intellectual disabilities. Fact Sheet: TYR III English

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Fatty Acid Oxidation Disorders

Fatty acid oxidation (FAO) disorders are rare disorders in which the body is not able to break down fatty acids. Without fatty acids, the body runs out of energy and cannot continue to function. Also, if fatty acids are not broken down, they build up in the body causing damage to important organs such as the heart and liver. Treatment may include a low fat diet, frequent food intake, supplementation with L-Carnitine (Carnitor) and medium-chain triglycerides.

Core Conditions

Carnitine Uptake Defect (CUD) is a condition in which the body cannot bring enough carnitine, a substance that helps the body make energy from fats, into the cells. The body is unable to break down certain fats. This can result in a build up of unused fatty acids. If untreated, CUD can cause can cause intellectual disability, an enlarged heart, weak muscles or death. Fact Sheets: CUD English - CUD Spanish

Long-Chain Hydroxyacyl-CoA Dehydrogenase Deficiency (LCHAD) is a condition in which the body is unable to break down certain fats and cannot change some of the fats into energy the body needs. LCHAD can cause periods of low blood sugar and if not treated, a child with LCHAD can develop breathing problems, swelling of the brain, seizures, and coma that can lead to death. Fact Sheets: LCHAD English -  LCHAD Spanish

Medium Chain Acyl-CoA Dehydrogenase (MCAD) is a condition in which the body is unable to break down certain fats and is unable to change them into energy the body needs. If untreated, MCAD can cause breathing problems and low blood sugar. Undetected, it can cause sudden death. Treatment includes ensuring frequent food intake. Fact Sheets: MCAD English - MCAD Spanish

Trifunctional Protein Deficiency (TFP) is a condition in which the body is not able to break down certain fats that the body needs for energy. Babies and young children with TFP should not go without food for more than 4 to 6 hours and sometimes more often. If not treated, a child with TFP can develop breathing problems, seizures, and coma that can lead to death. Fact Sheets: TFP English - TFP Spanish

Very-Long-Chain Acyl-Co A Dehydrogenase Deficiency (VLCAD) is a condition in which the body is unable to break down certain fats into energy. VLCAD can cause periods of low blood sugar and if not treated, a child with VLCAD can develop breathing problems, swelling of the brain, seizures, and coma, sometimes leading to death. Fact Sheets: VLCAD English - VLCAD Spanish

Secondary Conditions

2,4 Dienoyl-CoA Reductase Deficiency (DE RED) is an extremely rare condition in which the body is unable to break down certain fats. A baby with this condition had signs including small body and head size, short torso, arms, and fingers, weak muscle tone, poor appetite, vomiting, irritability, and delayed weight gain. Fact Sheets: DE RED English - DE RED Spanish

3-Hydroxyacyl-Coenzyme A Dehydrogenase Deficiency (HADH), previously named Medium/Short Chain Acyl-CoA Dehydrogenase (M/SCHAD), is a condition in which the body is unable to break down certain fats. Many people with HADH never have symptoms, but some experience serious health effects. Babies who do not receive treatment for HADH are at risk of life-threatening heart and breathing problems, brain damage, or coma. Fact Sheets: HADH/MSCHAD English - HADH/MSCHAD Spanish

Carnitine Acylcarnitine Translocase Deficiency (CACT) is a condition in which the body is unable to break down certain fats. Signs of CACT in babies include weak muscle tone, behavior changes, poor appetite, trouble breathing, seizures and developmental delays. Fact Sheets: CACT English - CACT Spanish

Carnitine Palmitoyl Transferase I Deficiency (CPT1) is a condition in which the body is unable to break down certain fats. Children with CPT1 usually start showing symptoms when they are 8 to 18 months old. If not treated, CPT1 can cause breathing problems, seizures, and coma, sometimes leading to death. Fact Sheets: CPT1 English - CPT1 Spanish

Carnitine Palmitoyltransferase Type II Deficiency (CPTII) is a condition in which the body is unable to break down certain fats. Signs of CPTII in babies include weak muscle tone, behavior changes, poor appetite, trouble breathing, seizures and developmental delays. Fact Sheets: CPTII English - CPTII Spanish

Glutaric Acidemia, Type II (GA2) is a condition in which the body is unable to break down certain fats and proteins. GA2 can cause weak muscle tone, severe heart problems, and death. Treatment may not be effective for some newborns with this condition. Fact Sheets: GA2 English - GA2 Spanish

Medium-Chain Ketoacyl-CoA Thiolase Deficiency (MCAT) is an extremely rare condition in which the body is unable to break down certain fats. Signs of MCAT include vomiting, weight loss, poor appetite, diarrhea, trouble breathing. Fact Sheet: MCAT English - MCAT Spanish

Short-Chain Acyl-CoA Dehydrogenase Deficiency (SCAD) is a condition in which the body is unable to break down certain fats. Each child with SCAD has a different experience. Signs of SCAD include behavior changes, irritable mood, poor appetite, trouble breathing and seizures. Fact Sheets: SCAD English - SCAD Spanish

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Organic Acid Disorders

Organic acid disorders are conditions that cause toxic organic acid products to build up because the body cannot breakdown certain amino acids and odd-chain organic acids. The human body uses amino acids to make proteins to help the body grow and work properly. Treatment includes restricting protein in the diet and supplementation with vitamins and/or L-Carnitine. 

Core Conditions

3-Methylcrotonyl-CoA Carboxylase Deficiency (3MCC) is a condition in which the body is unable to properly break down an amino acid called leucine. Harmful amounts of organic acids and toxins can build up in the body. Treatment often involves eating a low-leucine diet. If not treated, a child with 3MCC can develop breathing problems, seizures, liver failure, and coma, sometimes leading to death. Fact Sheets: 3MCC English - 3MCC Spanish  

3-Hydroxy-3methylglutaric Aciduria (HMG) is a condition in which the body is unable to break down certain proteins. People with the condition also are unable to produce ketone bodies, substances that help the body store energy. A child with HMG can develop breathing problems, heart enlargement, hearing loss, vision problems, seizures, and coma, sometimes leading to death. Fact Sheets: HMG English - HMG Spanish  

Beta-Ketothiolase Deficiency (BKT) is a condition in which the body is unable to break down break down an amino acid called isoleucine from food. All foods with protein contain isoleucine. A child with BKT can develop intellectual disability, muscle spasms, enlarged heart, higher risk for infections, and kidney problems. Fact Sheets: BKT English - BKT Spanish  

Glutaric Acidemia Type 1 (GA1) is a condition in which the body is unable to break down the amino acids lysine and tryptophan from foods. Newborns with GA1 are usually healthy, but many are born with a large head. If not treated, child with GA1 can develop tics or muscle spasms, poor coordination and balance, seizures, brain swelling, and coma, sometimes leading to death. Fact Sheets: GA1 English - GA1 Spanish 

Isovaleric Acidemia (IVA) is a condition in which the body is unable to break down isovaleric acid. This acid builds up in the blood and causes problems when a child with IVA eats food with leucine that is found in all foods with protein. If not treated, a child with IVA can develop breathing problems, seizures, intellectual disability, and coma that can lead to death. Fact Sheets: IVA English - IVA Spanish 

Methylmalonic Acidemia (MMA) (Cbl A and Cbl B forms) (Cbl A,B) is a condition in which the body is unable to break down certain fats and proteins. It can lead to a harmful amount of organic acids and toxins in the body. Signs of MMA Cbl A, B can include weak muscle tone, breathing trouble, frequent illnesses and infections, and increased bleeding and bruising. MMA Cbl AB Fact Sheet 

Methylmalonic Acidemia (mutase deficiency form) (MUT) is a condition in which the enzyme methylmalonyl-CoA mutase is not working correctly in the body. This enzyme helps break down odd-chain fatty acids and certain amino acids. Signs of MUT can include weak muscle tone, breathing trouble, frequent illnesses and infections, and increased bleeding and bruising. MUT Fact Sheet

Multiple Carboxylase Deficiency (MCD) is a condition in which the body cannot change protein and carbohydrates into energy. Harmful matter builds up in the blood and urine that can cause serious health problems. If not treated, a child with MCD can develop breathing problems, seizures, brain swelling, and coma that can lead to death. Fact Sheets: MCD English - MCD Spanish

Propionic Acidemia (PROP) is a condition in which the body is unable to break down certain proteins and fats. It can lead to a harmful amount of organic acids and toxins in the body. If left untreated, it can cause breathing problems, seizures, weak bones, skin rashes, poor growth, intellectual disability or even death. Fact Sheets: PROP English - PROP Spanish 

 

Secondary Conditions

2 Methylbutyryl-CoA Dehydrogenase Deficiency (2MBG) is a condition in which the body is unable to break down certain proteins. Very few cases of 2MBG have been reported. Signs of 2MBG include tiredness, irritability, vomiting, fever, weak muscle tone, delayed growth, tight muscles, and developmental delays. Fact Sheets: 2MBG English - 2MBG Spanish

2-Methyl-3-Hydroxybutyric Acidemia (2M3HBA) is a condition in which the body is unable to break down certain proteins. Children with 2M3HBA start showing signs during infancy, typically between 9 and 14 months. Males and females can have different signs of 2M3HBA. Males are more severely affected than females. Fact Sheets: 2M3HBA English - 2M3HBA Spanish

3-Methylglutaconic Aciduria (3MGA) is the name for a group of five different conditions in which the body is unable to break down certain proteins. The causes, symptoms, and treatment of the five different types of 3MGA vary, but they all begin in utero or at birth. Fact Sheets: 3MGA English - 3MGA Spanish

Isobutyrylglycinuria (IBG) is a condition in which the body is unable to break down certain proteins. IBG is a very rare condition. A child with IBG had signs that began at age one. Signs of IBG include delayed growth, tiredness, pale skin, trouble regulating body temperature, and difficulty breathing. Fact Sheets: IBG English - IBG Spanish

Methylmalonic Acidemia with Homocystinuria (Cbl C,D) is a condition in which the body is unable to process certain fats and proteins. Signs of Cbl C, D include delayed growth, small head size, skin rash, poor appetite and weak muscle tone. Fact Sheets: MMA Cbl C,D English - MMA Cbl C,D Spanish

Malonic Acidemia (MAL) is a condition in which the body is unable to break down certain proteins. There are very few reported cases of MAL. Signs and symptoms of the condition vary and can include developmental delays, weak muscle tone, diarrhea, vomiting, and seizures. Fact Sheets: MAL English - MAL Spanish

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Endocrine Disorders

Endocrine Disorders are rare disorders that affect the endocrine system which is a group of glands and organs in the body that produce, store and release hormones that help control important body functions.

Core Conditions

Congenital Adrenal Hyperplasia (CAH) is caused by decreased or absent production of certain adrenal hormones. Early detection can prevent death in boys and girls and sex misassignment in girls. Treatment involves lifelong hormone replacement therapy. Fact Sheets: CAH English - CAH Spanish

Congenital Hypothyroidism (CH) is a condition in which the thyroid gland does not make enough or any thyroid hormone. Thyroid hormone replacement therapy begun by one month of age can prevent intellectual and growth disabilities. Fact Sheets: CH English - CH Spanish 

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Hemoglobin Disorders

Hemoglobin Disorders are rare blood conditions caused by problems with hemoglobin which is a protein in the blood that carries oxygen. Persons of African or Mediterranean descent are at an increased risk. Early treatment with daily penicillin prevents death in the first few years of life. This is because infants and young children with these conditions have a higher risk of getting infections.

Core Conditions

Sickle Cell Anemia (Hb SS) is the most common sickle cell disease. It clogs blood vessels and causes severe pain. It also can cause problems such as organ and tissue damage. Fact Sheets: HbSS English - HbSS Spanish

Sickle Beta Zero Thalassemia (Hb S/Th) is a condition in which the hemoglobin is not normal and the red blood cells are small and pale. Problems can happen when different parts of the body do not get enough oxygen. Fact Sheets: HbSbTh English - HbSbTh Spanish 

Sickle-Hemoglobin C Disease (Hb S/C) is a “mild” form of sickle cell anemia. The red blood cells of a child with Hb S/C disease have two kinds of abnormal hemoglobin. Fact Sheets: HbSC English - HbSC Spanish

Secondary Conditions

Various Hemoglobinopathies (Var Hb) are inherited single-gene disorders. Mutations of the hemoglobin can have different effects on the red blood cell, such as shape of the cell or how well the cell carries oxygen. These abnormalities may cause conditions such as anemia, jaundice, and pain. Var Hb Fact Sheet

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Other Disorders

Core Conditions

Biotinidase Deficiency (BIOT) is a condition in which the body cannot use the vitamin called biotin. The body needs biotin to break down fats, proteins, and carbohydrates effectively. If not treated, a baby can have seizures, hearing loss, vision problems, and death in severe cases. Treatment involves daily doses of biotin. Fact Sheets: BIOT English - BIOT Spanish

Cystic Fibrosis (CF) is a condition that affects the lungs, digestive system, and overall growth. It causes thickened secretions, which clog the lungs and cause breathing problems. It also can affect the pancreas and make it hard to break down and absorb food. CF Fact Sheet. Additional information: Accredited Centers in TexasDNA Testing 40-Mutation PanelThings to Know About Cystic Fibrosis Brochure

Galactosemia (GALT) is a condition in which the body cannot break down galactose. Galactose is a sugar found in milk and milk products. It can lead to cataracts, liver cirrhosis, intellectual disability and/or death. Treatment is to remove galactose from the diet usually by substituting soy for milk products. Fact Sheets: GALT Engish - GALT Spanish

Severe Combined Immunodeficiency (SCID) is a condition in which the body’s immune system is not able to fight infection. Babies with SCID appear healthy at birth but can quickly become sick when exposed to common illnesses. SCID is so rare that medical providers might not diagnose it until it is too late to provide lifesaving treatment. Fact Sheets: SCID English - SCID Spanish

Spinal Muscular Atrophy (SMA) is an inherited condition that affects nerve cells (motor neurons) of the spinal cord and brain stem.  These motor neurons control certain muscles of the body.  Over time, as a child loses more motor neurons, the muscles get weaker. Activities such as crawling, walking, and breathing become more difficult.  Learning and intellectual abilities are not affected by SMA. Fact Sheet: SMA English 

X-Linked Adrenoleukodystrophy (X-ALD) is a condition in which the body’s cells cannot break down very long-chain fatty acids (VLCFAs). These build up and cause problems in the brain, spinal cord and adrenal glands. Fact Sheet: X-ALD EnglishX-ALD Spanish.

Secondary Conditions

T-Cell Related Lymphocyte Deficiencies are conditions in which the body’s immune system is not working properly. The body’s immune system is made up of different parts that work together to protect it from infection. T-cells are a specific type of white blood cell of the immune system that helps to protect the body from certain kinds of illnesses. Babies with T-cell deficiencies are born without enough working T-cells and may get repeated infections. Fact Sheets: T-Cell Related Lymphocyte Deficiencies English - T-Cell Related Lymphocyte Deficiencies Spanish

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Point-of-Service Screenings

 

Point-of-Service Screenings are tests done at the birthing facility before the baby goes home. These screenings are separate from the blood spot screening.

Critical Congenital Heart Disease (CCHD) refers to a group of serious heart defects that are present from birth. CCHD prevents the heart from pumping blood effectively or reduces the amount of oxygen in the blood. As a result, organs and tissues throughout the body do not receive enough oxygen that can lead to organ damage and life-threatening complications. Read more about CCHD.

Newborn Hearing Screening checks how well a baby can hear because some babies are born who deaf or hard of hearing. Most birthing facilities provide the screening before newborns go home. If a baby is born at home or in a birthing center that does not participate in hearing screening, they will refer parents to a certified program to schedule the hearing screening. Read more about newborn hearing screening. 

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