الفهرس 
Introduction
AminoacidopathiesOnly 14 pages are availabe for public view
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Abstract
Any of various disorders caused by a defect in an enzymatic step in the metabolic pathway of one or more amino acids or in a protein mediator necessary for transport of an amino acid into or out of a cell. This produces a metabolic block that results in accumulation of one or more amino acids in the blood (aminoacidemia) or excess excretion in the urine (aminoaciduria), or both. Inborn errors of metabolism are rare congenital diseases that are mainly due to a genetic defect of enzymes or cofactors participating in a certain metabolic pathway or the transport of metabolites within a cell or between cells. This can lead to: 1. Accumulation of substrate (e.g.Accumulation of methylmalonate in methylmalonyl-CoA mutase deficiency, methylmalonic academia) 2.Loss of end product(e.g. hypoglycaemia following defects in gluconeogenesis, or defective oxidative ATP energy production in mitochondrial diseases). 3. Accumulation of normally minor metabolites (e.g. Accumulation of propionic acid in methylmalonicacidaemia) 4.Secondary metabolic consequences (acidosis, ketosis, accumulation of lactate or ammonia). These may obscure the underlying metabolic disturbance and cause diagnostic confusion. • Definition of aminoacidopathies : Any of various disorders caused by a defect in an enzymatic step in the metabolic pathway of one or more amino acids or in a protein mediator necessary for transport of an amino acid into or out of a cell. This produces a metabolic block that results in accumulation of one or more amino acids in the blood (aminoacidemia) or excess excretion in the urine (aminoaciduria), or both. Inborn errors of metabolism are rare congenital diseases that are mainly due to a genetic defect of enzymes or cofactors participating in a certain metabolic pathway or the transport of metabolites within a cell or between cells.