Facts about the Maple Syrup Urine Disease

Details: Category: Region 9; Published: 18 July 2022

The National Organization for Rare Disorders defines maple syrup urine disease (MSUD) as a rare genetic disorder characterized by a lack of an enzyme complex (branched-chain alpha-keto acid dehydrogenase) that is necessary for the body to break down (metabolize) the three BCAAs, leucine, isoleucine, and valine. All three BCAAs, as well as a number of their toxic byproducts (specifically their respective organic acids), accumulate abnormally as a result of this metabolic failure. Within a few hours of birth, plasma concentrations of BCAAs start to increase in the classic, severe form of MSUD. Symptoms start to appear if left untreated, frequently within the first 24 to 48 hours of life.

BCAAs can be found in foods high in protein, such as meat, eggs, and milk, according to Anna Giorgi of Healthline. These substances can cause neurological damage, comas, and other life-threatening conditions as their levels rise. Dietary restrictions can be used to control MSUD. Blood tests can be used to track the effectiveness of this method. Early detection and treatment increase the likelihood of long-term success. According to the National Organization for Rare Disorders (NORD), both men and women experience MSUD at the same rate (about 1 in 185,000 people). Whether or not your parents are MSUD carriers affects your risk of developing the disease. In the event that both parents are carriers, their child has a 25% chance of inheriting two mutated genes and developing MSUD, a 50% chance of inheriting just one defective gene and being a carrier, and a 25% chance of inheriting one normal gene from each parent. You cannot pass BCKDC to your offspring if you have two normal BCKDC genes.

Lethargy, poor appetite, weight loss, weak sucking ability, irritability, a distinctive maple sugar odor in earwax, sweat, and urine, irregular sleep patterns, alternating episodes of hypertonia (muscle rigidity) and hypotonia (muscle limpness), and high-pitched crying are some of the initial symptoms Anna Giorgi listed as being typical of classic MSUD. Seizures, neurological deficits, developmental delays, feeding difficulties, poor growth, and a distinct maple sugar odor in earwax, sweat, and urine are among the symptoms of intermediate and thiamine-response MSUD.

How do medical experts identify MSUD? In order to avoid long-term harm, it is essential to detect MSUD at birth. When a child tests negative for MSUD and both parents are carriers, further testing may be advised to confirm the results and delay the onset of symptoms. Urine analysis or blood tests can be used to diagnose MSUD when symptoms emerge after the newborn stage. A high level of keto acids can be found in urine analysis, and a high level of amino acids can be found in a blood test.

If your baby is identified as having MSUD, Anna Giorgi advises seeking immediate medical attention to prevent serious health issues and intellectual disability. The first course of treatment entails lowering the blood levels of BCAAs in your infant. This typically entails the intravenous (IV) administration of amino acids devoid of BCAAs along with glucose for added caloric intake. Leucine, isoleucine, and valine already present in the body will be used more effectively as a result of the therapy. It will lower the BCAA level and supply the necessary protein at the same time. Together with a metabolic expert and a dietitian, your doctor will develop a long-term treatment plan for your child with MSUD.

There is no way to prevent MSUD because it is an inherited condition. Your risk of having a child with MSUD can be ascertained with the assistance of a genetic counselor. You can find out if you or your partner is a carrier of the disease through genetic testing. Before birth, a fetus with the disease can be detected through DNA testing. MSUD children can live normal, active lives. Your child can avoid potential complications with regular medical monitoring and careful adherence to dietary restrictions. However, a metabolic crisis can happen even with careful monitoring. If your child exhibits any MSUD symptoms, let your doctor know. The best outcomes can be obtained if treatment is initiated and continued as soon as possible.

DMO II Marie-Claire Gaas

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