TY - CHAP M1 - Book, Section TI - Hyperammonemia A1 - Jamuar, Saumya S. A1 - Levy, Harvey L. A2 - Murray, Michael F. A2 - Babyatsky, Mark W. A2 - Giovanni, Monica A. A2 - Alkuraya, Fowzan S. A2 - Stewart, Douglas R. PY - 2014 T2 - Clinical Genomics: Practical Applications in Adult Patient Care AB - Disease summary:Hyperammonemia in adults has many different causes. Most are nongenetic. Infrequent but important genetic causes are defects in the urea cycle which are life threatening and treatable.Urea cycle disorders (UCDs) are caused by defects in the metabolic cycle which converts ammonia to urea.The adult phenotype may present dramatically or subtly with hyperammonemia of varying degree that can produce cerebral edema. The clinical features include psychosis, altered mental status, vomiting, and focal neurologic signs, or lethargy progressing to obtundation and coma. Acute episodes are often precipitated by surgery, pregnancy, or more likely the postpartum, trauma, and infection.Chronic features include cognitive and learning deficits, intermittent headaches, intermittent visual disturbances, and focal neurologic signs. There may also be a lifelong aversion to dietary protein.Hereditary basis:All the UCDs are inherited in an autosomal recessive manner with the exception of ornithine transcarbamylase (OTC) deficiency which is X-linked.Differential diagnosis:Liver failureSepsisValproate therapy SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accessmedicine.mhmedical.com/content.aspx?aid=1102703272 ER -