Urea cycle disorders: a case report of a successful treatment with liver transplant and a literature review.

The urea cycle is the final pathway for nitrogen metabolism. Urea cycle disorders (UCDs) include a variety of genetic defects, which lead to inefficient urea synthesis. Elevated blood ammonium level is usually dominant in the clinical pattern and the primary manifestations affect the central nervous system. Herein, we report the case of a 17-year-old girl who was diagnosed with UCD at the age of 3. Despite a controlled diet, she was hospitalized several times for acute attacks with recurrent life risk. She came to our attention for a hyperammonemic episode. We proposed an orthotopic liver transplant (OLT) as a treatment; the patient and her family were in complete agreement. On February 28, 2007, she successfully received a transplant. Following the surgery, she has remained well, and she is currently leading a normal life. Usually for UCDs diet plays the primary therapeutic role, while OLT is often considered as a last resort. Our case report and the recent literature data on the quality of life and prognosis of traditionally treated patients vs OLT patients, support OLT as a primary intervention to prevent life-threatening acute episodes and chronic mental impairment.

A case of carbamoyl phosphate synthetase 1 deficiency presenting symptoms at one month of age.

Carbamoyl phosphate synthetase 1 deficiency (CPS1D) is an autosomal recessive disorder of the urea cycle which causes hyperammonemia. Two forms of CPS1D are recognized: a lethal neonatal type and a less severe, delayed onset type. Neonatal CPS1D cases often present their symptoms within the first days of life. Delayed onset type were adolescents or adults, and infantile cases were rare. We report a case of CPS1D in a boy who developed symptoms at one month of age. He showed excellent response to treatments including continuous hemodialysis, drugs and a low-protein diet. His development and weight gain were good at the last follow-up at 1 year and three months of age. Molecular assay of the CPS1 gene demonstrated that the patient was heterozygous for c.2407C>G (R803G: maternal) in exon 20 and c.3784C>T (R1262X: paternal) in exon 32. Our clinical experience suggests that CPS1D could be one of the causes of hyperammonemia in early infantile cases.