It’s rare disease month and I thought I would share a little about the Urea Cycle Disorder my son was born with. Diagnosed at the age of four, urea cycle disorder, is a rare genetic disorder that affects the body’s ability to remove waste products from the blood. We didn’t know the type he had until his liver transplant a year later and they did a biopsy to confirm the doctor’s suspicion.
There are several different types of urea cycle disorders, each with its own specific genetic mutations and symptoms. One of the most severe types is CPS1 deficiency, which can lead to life-threatening complications if left untreated. And I just want to emphasize that he went undiagnosed for 4 years before we knew what was happening. I wrote a book called Lennon Steps to share his story.

CPS1 (carbamoyl phosphate synthetase 1) is an enzyme that is essential for the proper function of the urea cycle. The urea cycle is responsible for converting toxic ammonia into urea, which can be safely excreted by the body. In individuals with CPS1 deficiency, the enzyme is either absent or not functional, leading to a buildup of ammonia in the blood.
Symptoms of CPS1 deficiency can vary depending on the severity of the disorder. In severe cases, symptoms may appear shortly after birth and can include seizures, lethargy, vomiting, and difficulty breathing. In milder cases, symptoms may not appear until later in life and can include fatigue, nausea, and cognitive difficulties. My son had his symptoms since birth but because it is rare no one knew what to look for. He was non-verbal and developmentally delayed due but more than anything we bounced back and forth from lethargy to vomiting for days to days that were perfectly fine.
Diagnosis of CPS1 deficiency usually involves a combination of genetic testing and blood tests to measure ammonia levels in the blood. Treatment typically involves managing symptoms and preventing the buildup of ammonia in the blood. This can include a low-protein diet, medication to help remove excess ammonia from the body, and in severe cases, a liver transplant.
Once my son was officially diagnosed, he was allotted 18 grams of protein a day and after 35 hospital visits within a year, some just days apart, his doctor recommended him a liver transplant.
Living with CPS1 deficiency can be challenging, both for individuals with the disorder and their families. In addition to medical management, individuals with CPS1 deficiency may require special accommodations, such as modifications to their diet or assistance with daily activities.
Despite the challenges, individuals with CPS1 deficiency can lead full and meaningful lives with the proper medical care and support. Advances in genetic testing and treatment have led to improved outcomes for individuals with urea cycle disorders, including CPS1 deficiency.
Awareness and education about urea cycle disorders, including CPS1 deficiency, are essential for early diagnosis and treatment. This can help prevent life-threatening complications and improve the quality of life for individuals with the disorder. By supporting research and advocating for a better understanding and treatment of urea cycle disorders, we can improve the lives of those affected by these rare and complex conditions.
And as I mentioned because life for my son became hard to manage and death felt really close, he received a new liver in 2008. I got into more details about the book because that was a whole other journey we were not prepared for.
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