organic acidaemia

organic acidaemia

A nonspecific term for a group of metabolic disorders characterised by a defect of metabolism of organic acids (especially branched-chain amino acids—isoleucine, leucine and valine), resulting in their accumulation in the circulation and excretion in the urine.
 
Clinical findings
Developmental delays, poor feeding, lethargy, vomiting, dehydration, malnutrition, hypoglycaemia, hypotonia, metabolic acidosis, ketoacidosis, hyperammonaemia and, untreated, death.
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References in periodicals archive ?
It is one of the cerebral organic acidaemia, which lacks general metabolic derangements like hypoglycaemia, metabolic acidosis or hyperammonaemia seen in inherited metabolic disorders presenting with metabolic decompensation.
Hyperammonaemia is a metabolic disturbance of the urea cycle characterised by an excess of ammonia in the blood.(1) Hyperammonaemia may develop soon after birth (early onset), or in childhood, adolescence or adulthood (late onset) and can be inherited or acquired.(2) Urea cycle disorders are extremely rare with an overall prevalence estimated at 1:8,000-1:44,000 births.(3) However, these values may be underestimated due to under-diagnosis, misdiagnosis and absent neonatal screening programmes.(3) Organic acidaemias are also rare, with a European prevalence estimated at 1:29,000-1:65,000(4).
These cases represent over 60% of all IMDs diagnosed in this period and the majority fall into 3 main categories, namely the organic acidaemias (OAs), the urea cycle defects (UCDs) and the mitochondrial cytopathies.
* metabolic diseases such as Wilson's disease, alpha 1 antitrypsin deficiency, Crigler-Najjar syndrome, and other inborn errors of metabolism (tyrosinaemia, hyperoxaluria, organic acidaemias)
The determination of carnitine levels by electrospray tandem mass spectrometry using dried blood spot in filter paper, for the detection of defects in fatty acid oxidation and organic acidaemias, has been described (12-14), the butylester derivatives and underivatized carnitine and acylcarnitines share a common product ion, which is singly charged with a mass of 85 Da, and thus allows the use of MS/ MS for the analysis of these compounds (15), however the methods used for measuring carnitine and acylcarnitines can be influenced by several factors when samples are obtained or even during the laboratory procedure when samples are analysed (16).