Carbamoyl phosphate synthetase I deficiency (CPS) is a rare genetic condition. CPS results from a mutation (error) in the CPS1 gene. People with CPS cannot remove ammonia from their bodies. Ammonia is produced during the break down of proteins. Normally, our liver changes ammonia into less harmful urea which we then get rid of in our urine. This process is called the urea cycle and it depends on a number of special proteins (enzymes). If one of the enzymes needed is missing or not working correctly, the ammonia is not changed into urea and cannot be excreted in our urine. In CPS, the enzyme carbamoyl phosphate synthetase (CPS) is not working causing ammonia to build up in the bloodstream. Ammonia is very toxic. The brain is very sensitive to ammonia. p>
Signs of the most common form of CPS usually show shortly after birth. In the second form signs may begin to show during childhood or adulthood. Symptoms of CPS include poor appetite, vomiting, tiredness, seizures, trouble breathing, uncontrolled body movements, or delayed growth. Lack of treatment may lead to a coma. Treatment may include a specific diet to limit proteins as well as special medication. Special foods or formulas may also be needed. Lifelong management is needed to avoid delayed development and intellectual disabilities.
CPS is autosomal recessive. Early diagnosis has shown to be effective in improving the health of individuals with CPS Many babies are screened at birth so that treatment may begin early, however the conditions included in newborn screening vary state by state. For more information, visit Baby’s First Test. Talk with your doctor to determine which treatment options are best for your child. Support groups are a good source of information. A genetic counselor will help you understand the genetics.