methylmalonic acidemia (mma) is usually caused by a deficiency of the enzyme methylmalonyl-coa mutase (mcm), a defect in the transport or synthesis of its cofactor, adenosyl-cobalamin (cbla, cblb, cblc, cblf, cbld, and cblx), or deficiency of the enzyme methylmalonyl-coa epimerase. a comprehensive diagnostic approach involves investigations of metabolites with tandem mass spectrometry, organic ...

A gas-chromatographic method for urinary organic acid analysis is described, designed to be used routinely for the diagnosis of organic aciduria. It involves extraction of urine with ethyl acetate, dehydration of extract residues, and trimethylsilylation. Organic acids are identified by using an extensive list of retention indices published in the accompanying paper (this issue). Quantitative v...

Ikeda, M., and Ohtsuji, H. (1969). Brit. J. industr. Med., 26, 162-164. Hippuric acid, phenol, and trichloroacetic acid levels in the urine of Japanese subjects with no known exposure to organic solvents. Urine samples from 36 male and 30 female university students and 31 male factory workers with no known exposure to industrial organic solvents were analysed for hippuric acid, phenol, and tric...

a clinical presentation of a metabolic disorder, often first seen in infants who present with poor feeding, vomiting, tachypnea, acidosis, hyperammonemia, ketosis, ketonuria, irritability, and convulsions or hypotonia and lethargy, findings that are otherwise suggestive of neonatal sepsis diseases with oa isovaleric and propionic acidemias, maple syrup urine disease, medium chain acyl dehydroge...

Results We diagnosed 148 cases of IEM by urine GC-MS analysis, including 97 cases of organic acid disorders, 41 cases of amion acid disorders and 10 cases of fatty acid oxidative disorders. Methylmalonic aciduria (MMA) was most common (48 cases), followed by urea cycle disorder (21 cases), phenylketonuria (20 cases), propionic aciduria (11 cases), multiple carboxylase deficiency (8 cases), glut...

BACKGROUND The finding reported in a previous paper - alkalization of urine facilitates uric acid excretion - is contradictory to what one might expect to occur: because food materials for the alkalization of urine contain fewer purine bodies than those for acidification, less uric acid in alkaline urine should have been excreted than in acid urine. To make clear what component of uric acid exc...

A rapid and accurate quantitative method was developed and validated for the analysis of four urinary organic acids with nitrogen containing functional groups, formiminoglutamic acid (FIGLU), pyroglutamic acid (PYRGLU), 5-hydroxyindoleacetic acid (5-HIAA), and 2-methylhippuric acid (2-METHIP) by liquid chromatography tandem mass spectrometry (LC/MS/MS). The chromatography was developed using a ...