What are the main symptoms of argininemia?
Some infants and children who were promptly diagnosed and treated before symptoms begin, have remained symptom-free. According to the medical literature, this has been true for people who are now more than 35 years old. If symptoms were already present when treatment was started, good results can still be achieved. This is true if treatment is started before significant problems developed. The progression of neurological disease can be stopped and some skills can be reacquired. However, not all infants and children will respond to treatment and treatment cannot repair damage that has already occurred. Consequently, life expectancy will depend on several factors including when the disorder was first diagnosed, what symptoms have already developed and how an individual person or child responds to treatment.
Most infants are normal during the newborn period. They may be irritable, have problems feeding, and may become very sleepy (lethargic) when first introduced to cow's milk. If untreated, symptoms usually become apparent around 1 to 4 years of age. Children may be clumsy and may fail to gain weight or grow as would be normally expected. The may vomit repeatedly, experience nausea, and may not want to eat (food aversion). They may have delays in reaching developmental milestones and may lose skills that they had already developed. The liver may be enlarged. A children's head circumference may be smaller than otherwise would be expected, a condition called microcephaly. Some children may walk on their toes. Seizures are common and intellectual disability, tremors, and a condition called spasticity also develop. Spasticity is when there is increased muscle tone and stiffness of leg muscles and can cause muscle spasms. If the disorder remains untreated, the neurological symptoms will worsen and severe intellectual disability, an inability to walk and other severe symptoms can develop.
Sometimes infants or children with argininemia can have a metabolic crisis. This is uncommon, although in other urea cycle disorders it is much more frequent. During a metabolic crisis, an infant may vomit, refuse to eat, become increasingly lethargic, and eventually end up in a coma. A severe metabolic crisis is a life-threatening complication. In argininemia, ammonia does build up as much as it does in other urea cycle disorders and an episode of metabolic crisis is rare. When children with argininemia have an episode, it is usually not as severe and can be treated with intravenous fluids.
Some people have developed damage to the liver and excessive wound healing called hepatic fibrosis. This means a lot of fibrous tissue builds up in the liver. Some people may have scarring in the liver, which is called cirrhosis. These liver problems can be severe enough to require a liver transplant.
SOURCE: Emory University - Department of Human Genetics in collaboration with ThinkGenetic • https://www.thinkgenetic.com/diseases/argininemia/symptoms/36487 • DATE UPDATED: 2019-06-17
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