Nonketotic Hyperglycinemia is a rare genetic disorder characterized by excessive levels of glycine in the blood and cerebrospinal fluid. The word is spelled as "non-ke-tot-ic hy-per-gly-cin-emia" and its phonetic transcription is /nɑnˌkiːtəˈtɑtɪk ˌhaɪpərˌɡlaɪˈsɪnəmiə/. The pronunciation highlights the stress on the syllables "ke", "gly", and "mia". Nonketotic Hyperglycinemia can lead to developmental delays, seizures, and intellectual disabilities. Early diagnosis and treatment are crucial for managing symptoms and improving quality of life.
Nonketotic Hyperglycinemia (NKH) is a rare, genetic, metabolic disorder characterized by elevated levels of glycine, a neurotransmitter, in the body. This condition is caused by a deficiency or dysfunction of the glycine cleavage system (GCS), an enzyme responsible for breaking down glycine.
In individuals with Nonketotic Hyperglycinemia, glycine accumulates in the brain and other organs, leading to severe neurologic symptoms. These symptoms usually become apparent in the first days or weeks of life and may include low muscle tone, weak cry, lethargy, feeding difficulties, seizures, and breathing problems. Some affected individuals may exhibit developmental delays, intellectual disabilities, and may have difficulties with movement and coordination.
Nonketotic Hyperglycinemia is an autosomal recessive disorder, meaning it requires both parents to carry and pass on a nonfunctional or mutated gene to the child for the condition to develop. Genetic mutations in genes associated with the glycine cleavage system, including the GLDC, AMT, and GCSH genes, have been implicated in causing NKH.
The diagnosis of Nonketotic Hyperglycinemia typically involves a combination of clinical evaluation, blood tests to measure glycine levels, and genetic testing to identify specific mutations. Unfortunately, there is currently no cure for Nonketotic Hyperglycinemia, and treatment mainly focuses on managing symptoms and providing supportive care. This may include medications to help reduce glycine levels and control seizures, as well as physical, occupational, and speech therapies to address developmental delays and improve motor skills.
Overall, Nonketotic Hyperglycinemia is a rare metabolic disorder characterized by elevated levels of glycine due to a deficiency in the glycine cleavage system, resulting in severe neurologic symptoms.
The term "nonketotic hyperglycinemia" can be broken down into its individual components.
1. Nonketotic: The prefix "non-" means "not" or "lacking", and "ketotic" refers to a condition called ketosis, in which the body produces high levels of ketones. In the case of nonketotic hyperglycinemia, the individual does not exhibit ketosis.
2. Hyperglycinemia: This term is composed of "hyper", which means "excessive" or "abnormally high", and "glycinemia", which refers to the presence of the amino acid glycine in the blood. Therefore, hyperglycinemia describes an abnormally high concentration of glycine in the blood.
Taken together, "nonketotic hyperglycinemia" describes a condition characterized by high levels of glycine in the blood, without the presence of ketosis.