Urea cycle disorders are inherited deficiencies of the enzymes involved in the cellular excretion of excess ammonia produced during protein metabolism. Hyperammonemia associated with these disorders is usually manifested by decreased level of consciousness, irritability, seizures, vomiting, and poor feeding. Although the majority of recognized patients are children, a delayed presentation is se...

Emerging evidence suggests that protein acetylation is a broad-ranging regulatory mechanism. Here we utilize acetyl-peptide arrays and metabolomic analyses to identify substrates of mitochondrial deacetylase Sirt3. We identified ornithine transcarbamoylase (OTC) from the urea cycle, and enzymes involved in β-oxidation. Metabolomic analyses of fasted mice lacking Sirt3 (sirt3(-/-)) revealed alte...

We report on an adult patient with citrin deficiency in Hong Kong, in whom a novel mutation was identified. The patient presented with recurrent hyperammonaemic encephalopathy due to impairment of the liver urea cycle enzyme argininosuccinate synthetase. This autosomal recessive condition is also characterised by interesting food preferences, notably aversion to carbohydrates and craving for pr...

Background: The diagnosis of inborn errors of metabolism is generally challenging. We aimed to explore various types of urea cycle disorders (UCDs), and their clinical presentations and biochemical findings among Egyptian pediatric patients. Materials and Methods: This case-control study was conducted on 86 participants categorized into ...

Ornithine carbamoyltransferase (OTC) deficiency is a urea cycle disorder that causes the accumulation of ammonia, which can lead to encephalopathy. Adults presenting with hyperammonemia who are subsequently diagnosed with urea cycle disorders are rare. Herein, we report a case of a late-onset OTC deficient patient who was successfully treated with arginine, benzoate and hemodialysis. A 59-yr-ol...

The urea cycle functions to incorporate ammonia, generated by normal metabolism, into urea. Urea cycle disorders (UCDs) are caused by loss of function in any of the enzymes responsible for ureagenesis, and are characterized by life-threatening episodes of acute metabolic decompensation with hyperammonemia (HA). A prospective analysis of interim HA events in a cohort of individuals with ornithin...

introduction citrullinemia is a defect in the urea cycle that causes ammonia to accumulate in the blood. we describe the anesthetic management of a patient with citrullinemia, who experienced an unexpected 10 day hospital admission. case presentation we anesthetized a 3.5 year-old boy with citrullinemia who was scheduled for a dentistry procedure. perioperative precautions included minimizing f...

Carbamoyl phosphate synthetase 1 (CPS1) is the first and rate-limiting enzyme in the urea cycle. CPS1 deficiency is a devastating condition, which is clinically characterized by periodic episodes of life-threatening hyperammonemia. Currently, there is no cure for CPS1 deficiency except for liver transplantation, which is limited by a severe shortage of donors and significant risk of mortality a...

Citrullinaemia is a urea cycle defect that results from a deficiency of the enzyme arginosuccinate synthetase. Type 1 disease is diagnosed in childhood, whereas Type 2 disease is adult onset. We report the outcome of a patient with citrullinemia Type 2 who received a liver transplant at our center and the implications of this diagnosis in liver transplantation.

Citrullinemia is a rare autosomal recessive inborn error of the urea cycle due to a deficiency in argininosuccinic acid synthetase. We present two cases of the infantile form of citrullinemia in which CT revealed bilateral and symmetric corticosubcortical hypoattenuating areas, ulegyric changes, and atrophy in the frontal lobes, as well as atrophy in the gyrus cinguli, insulae, and temporal lobes.