maple syrup urine disease symptoms in newborn

Maple syrup urine disease symptoms in newborn code#

Symptoms include fussiness, lethargy, decreased nursing/feeding, poor weight gain, hypotonia (poor muscle tone) or hypertonia (excessive muscle tension), vomiting, a high-pitched cry, seizures and the characteristic maple syrup smell of the urine-more noticeable in a diaper after it is dried. In infants with intermediate MSUD, symptoms are milder and may not be apparent as soon. Infants with classic MSUD appear normal at birth with symptoms appearing within 3 to 7 days. Thus, many neonates are diagnosed only after they start showing symptoms of MSUD. Furthermore, the methods used by some states are outdated and can be inaccurate. Unfortunately, many states do not include MSUD in their newborn screening programs.

Infants can be screened for MSUD through mandatory state screening programs. In most cases only moderate protein restriction is needed for this more rare type of MSUD. Giving large doses of thiamine to the thiamine-responsive child will increase the enzyme activity which breaks down leucine, isoleucine and valine. Thiamine-responsive MSUD is basically just what the name implies. During episodes of illness or fasting the BCAA levels elevate, the characteristic maple syrup (or burnt sugar) odor becomes evident and the child can go into a metabolic crisis. Often the child does not have symptoms until 12 to 24 months of age, usually in response to an illness or surge in protein intake. Intermittent MSUD is a milder form of the disease because of the greater enzyme activity present (approximately 8 to 15% of normal). Management is similar for the intermediate and classic types of MSUD. However, when ill or fasted, the child with intermediate MSUD reacts just like a child with classic MSUD. They can usually tolerate a greater amount of leucine. Those with intermediate MSUD have a higher level of enzyme activity (approximately 3 to 8% of normal). Intermediate MSUD is a variant of the classic type of the disease. They generally have poor tolerance for the BCAA, so protein must be severely restricted in their diet. Infants with classic MSUD will show symptoms within the first several days of life. In classic MSUD, little or no enzyme activity (usually less than 2% of normal) is present. These terms refer to the amount and type of enzyme activity present in the affected child which can vary considerably within each classification.Ĭlassic is the most common type of MSUD. When parents are both carriers of the gene for MSUD, with each pregnancy, there is a 1 in 4 chance of having a baby with MSUD, a 2 in 4 chance that the baby will have only one gene for MSUD and be a carrier like the parents, and a 1 in 4 chance that the baby will neither be a carrier nor have MSUD.įour general classifications are used to identify the types of MSUD: classic, intermediate, intermittent and thiamine responsive. It is also possible to receive the normal gene from each parent and not have any mutated genes for the disease. If neither gene functions normally, then that person has MSUD. If one gene functions normally, but the other does not, then the person is a carrier of MSUD.

Maple syrup urine disease symptoms in newborn code#

(Just as everyone carries genetic codes, such as those for the color of hair and eyes, everyone also carries several abnormal genes which can cause disease.)Įach individual person has two genes that code for the enzyme activity involved in the breakdown of the BCAAs-one gene coming from the father and one from the mother. Carriers are not affected by their one abnormal gene. A person with a gene mutation is called a carrier.

These mutated genes do not function normally, thus causing disease. This means both parents of a child with MSUD must carry a mutation in the same gene (the same genetic code). It is these elevations that cause an infant or child with MSUD to become symptomatic. Because of the enzyme deficiency in MSUD, the BCAAs and their byproducts, called ketoacids, become elevated. In MSUD, the enzymes necessary to break down leucine, isoleucine and valine, are either absent, inactive, or only partially active. The nonessential amino acids can be obtained from the diet or produced in the body from other amino acids. The essential amino acids must be supplied in the daily diet. Protein in the body is made up of a total of 20 amino acids, eleven of these are essential and nine are nonessential. These three amino acids-leucine, isoleucine and valine-are often called the branched-chain amino acids (BCAA). Maple Syrup Urine Disease (MSUD) is a disorder in the body's ability to use three of the essential amino acids in protein.