Systemic Biomarkers of Brain Injury From Hyperammonemia
Children's National Research Institute
Summary
Ammonia is a waste product of protein and amino acid catabolism and is also a potent neurotoxin. High blood ammonia levels on the brain can manifest as cytotoxic brain edema and vascular compromise leading to intellectual and developmental disabilities. The following aims are proposed: Aim 1 of this study will be to determine the chronology of biomarkers of brain injury in response to a hyperammonemic (HA) brain insult in patients with an inherited hyperammonemic disorder. Aim 2 will be to determine if S100B, NSE, and UCHL1 are altered in patients with two other inborn errors of metabolism, Maple Syrup Urine Disease (MSUD) and Glutaric Acidemia (GA1).
Description
Ammonia is a waste product of protein and amino acid catabolism and is also a potent neurotoxin. The onslaught of high blood ammonia levels on the brain can manifest as cytotoxic brain edema and vascular compromise leading to intellectual and developmental disabilities. In addition, clinical hyperammonemia recurs at varying intervals, which can increase the cumulative damage to the brain and the chance of irreversible coma and death during a hyperammonemia episode due to vascular compromise or brain herniation. The threshold of tolerance for elevated blood ammonia is very low and concentration…
Eligibility
- Age range
- 7–18 years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: 1. Inherited Hyperammonemias: 1. A clinical diagnosis of 1 of 7 diagnosed urea cycle disorders: * N-acetylglutamate Synthetase Deficiency (NAGS) * Carbamyl Phosphate Synthetase Deficiency (CPSD) * Ornithine Transcarbamylase Deficiency (OTCD) * Argininosuccinate Synthetase Deficiency (ASD) * Argininosuccinate Lyase Deficiency (ALD) * Arginase Deficiency (AD) * Hyperammonemia-Hyperornithinemia-Homocitrullinuria (HHH) 2. A clinical diagnosis of 1 of 2 organic acidemias: * Propionic Acidemia (PA) * Methylmalonic Ac…
Location
- Children's National Research InstituteWashington D.C., District of Columbia