- The Urea Cycle is the metabolic pathway that transforms nitrogen from peripheral (muscle) and enteral sources (protein ingestion) into urea that is water soluble and can be excreted. Deficiency of an enzyme in the pathway causes a urea cycle disorder (UCD). Examples of UCDs include carabmyl phosphate synthetase I deficiency, ornithine transcarbamylase deficiency or arginase deficiency amongst others. All UCDs except for arginase deficiency, result in hyperammonaemia and life-threatening metabolic decompensations in infancy. If the patient survives, there is usually a severe neurologic injury. The inheritance of the UCDs is autosomal recessive except for ornithine transcarbamylase (OTC) deficiency which is X-linked.
- The Igenomix Urea Cycle Disorder Precision Panel can be used to make an accurate and directed diagnosis ultimately leading to a better management and prognosis of the disease. It provides a comprehensive analysis of the genes involved in this disease using next-generation sequencing (NGS) to fully understand the spectrum of relevant genes involved.
- The Igenomix Urea Cycle Disorder Precision Panel is indicated for those patients with a clinical suspicion or diagnosis with or without the following manifestations during the newborn period:
- Decreased level of consciousness
- Altered mental status
- Abnormal motor function
- Poor feeding
- Inability to maintain body temperature
- Hyperammonemia and hyperventilation
The clinical utility of this panel is:
- The genetic and molecular confirmation for an accurate clinical diagnosis of a symptomatic patient.
- Early initiation in the form of rehydration and maintenance of good urine output without overhydration, remove nitrogen (ammonia) from the body with medications and/or haemodialysis, decrease protein intake and minimize catabolism, stimulate anabolism and uptake of nitrogen precursors by muscle.
- Risk assessment and genetic counselling of asymptomatic family members according to the mode of inheritance.
- Improvement of delineation of genotype-phenotype correlation.
Mew, N., Simpson, K., Gropman, A., Lanpher, B., Chapman, K., & Summar, M. (2021). Urea Cycle Disorders Overview. Retrieved 5 April 2021, from http://www.ncbi.nlm.nih.gov/books/NBK1217
Batshaw ML, Tuchman M, Summar M, et al. A longitudinal study of urea cycle disorders. Mol Genet Metab 2014; 113:127.
Leonard, J., & Morris, A. (2002). Urea cycle disorders. Seminars In Neonatology, 7(1), 27-35. doi: 10.1053/siny.2001.0085
Matsumoto, S., Häberle, J., Kido, J., Mitsubuchi, H., Endo, F., & Nakamura, K. (2019). Urea cycle disorders-update. Journal of human genetics, 64(9), 833–847. https://doi.org/10.1038/s10038-019-0614-4
Häberle, J., Burlina, A., Chakrapani, A., Dixon, M., Karall, D., Lindner, M., Mandel, H., Martinelli, D., Pintos-Morell, G., Santer, R., Skouma, A., Servais, A., Tal, G., Rubio, V., Huemer, M., & Dionisi-Vici, C. (2019). Suggested guidelines for the diagnosis and management of urea cycle disorders: First revision. Journal of inherited metabolic disease, 42(6), 1192–1230. https://doi.org/10.1002/jimd.12100
Lilliu, F. (2010). Treatment of organic acidurias and urea cycle disorders. The Journal Of Maternal-Fetal & Neonatal Medicine, 23(sup3), 73-75. doi: 10.3109/14767058.2010.509932