For some years now, urinary amino acid screening for inborn errors of metabolism has been routine in many institutions. In the early 1960’s, Cox and White (1) as well as Barness et a!. (2) showed the importance of measuring methylmalonate excretion in the urine of patients suffering from pernicious anemia. Since that time, detection of non-nitrogenous organic acids has taken on an importance si...

organic acidemias, also known as organic acidurias, are a group of disorders characterized by increased excretion of organic acids in urine. they result primarily from deficiencies of specific enzymes in the breakdown pathways of amino acids or from enzyme deficiencies in beta oxidation of fatty acids or carbohydrate metabolism. organic acids also are found in the urine of some patients with mi...

From June 1998 to May 2007, 9566 urine samples were collected from patients with psychomotor deficits, seizures, vomiting and unconsciousness in Peking University First Hospital. Their urine organic acids profiles were analysed using gas chromatography - mass spectrometry (GCMS), GCMS solution and Inborn Errors of Metabolism Screening System software. In all patients, blood acylcarnitines were ...

A cold vapor atomic absorption technique for blood or urine mercury analysis that uses persulfate oxidation to prepare samples for total mercury analysis and acid permanganate oxidation to prepare samples for inorganic mercury analysis is described. The linearity of the procedures ranged from 0.5 to 25 micrograms/L. Precision ranged from 20% at 1 microgram/L to 7% at 20 micrograms/L. Documentat...

glutaric acidemia, type i (ga i), was first described in 1975. the disease is caused by a genetic deficiency of the enzyme, glutaryl-coa dehydrogenase (gcd), which leads to the buildup of glutaric acid in the tissues and its excretion in the urine of affected patients. gcd is involved in the catabolism of the amino acids, lysine, hydroxylysine, and tryptophan. over 200 cases of ga i have been r...

BACKGROUND Maple syrup urine disease (MSUD) is the most common inborn error of metabolism in the country. The cause of the neuropathology is still not well established although accumulation of branched chain amino acids (BCAA) and alteration in large neutral amino acids (LNAA) as well as energy deprivation are suggested. It is therefore the aim of this study to determine the plasma amino acid a...

a 2-year-old boy was born at term of healthy, non-consanguineous iranian parents. his mother attended in the clinic with the history of sometimes discoloration of diapers after passing urine. she noticed that first at the age of one month with intensified in recent months. his physical examination and growth parameters were normal. his mother denied taking any medication (sorbitol, nitrofuranto...

In order to examine correlations which might be useful in ascertaining or confirming the diagnosis of mitochondrial disease, a retrospective analysis of urine organic acids was performed. Among 3646 analyses from randomly selected samples referred to our laboratory, there were 258 specimens from 67 patients with various known disorders of mitochondrial oxidative function, most of whom were know...