Urea Cycle Disorders

Disorder of urea cycle metabolism and ammonia detoxification is a genetic disorder that results in a deficiency of one of the six enzymes in the urea cycle. These enzymes are responsible for removing ammonia from the blood stream. The urea cycle involves a series of biochemical steps in which nitrogen, a waste product of protein metabolism, is changed to a compound called urea and removed from the blood. Normally, the urea is removed from the body through the urine. In Disorder of urea cycle metabolism and ammonia detoxification, nitrogen builds up in the blood in the form of ammonia, a highly toxic substance, resulting in hyperammonemia (elevated blood ammonia). Ammonia then reaches the brain through the blood, where it can cause irreversible brain damage, coma and/or death. The severity correlates with the amount of urea cycle enzyme function.

Genetic Mutations: Disorder of urea cycle metabolism and ammonia detoxification is caused by genetic mutations, also known as pathogenic variants. Genetic mutations can be hereditary, when parents pass them down to their children, or they may occur randomly when cells are dividing. Genetic mutations may also result from contracted viruses, environmental factors, such as UV radiation from sunlight exposure, or a combination of any of these.

If you suspect you may have this disease, you may want to start collecting your family health history. Information such as other family members who have had similar symptoms, when their/your symptoms first appeared, or exposures to any potential disease-causing environmental factors should be discussed with your medical team.

Disruption in Metabolism: Disorder of urea cycle metabolism and ammonia detoxification is caused by a disruption in a person's metabolism. Metabolism is the series of chemical reactions in our body that turns the food we eat into energy and removes toxins. Hormones and specific proteins, called enzymes, help make the right chemical reactions happen in the right order. However, genetic changes can prevent hormones or enzymes from working properly, which can lead to a disruption in metabolism such as energy not being created for the body or toxins not being removed from the body.