title: Simple high-performance liquid chromatographic method for the detection of phenylpropionylglycine in urine as a diagnostic tool in inherited medium-chain acyl-coenzyme A dehydrogenase deficiency.
abstract: Deficiency of medium-chain acyl-CoA dehydrogenase is a frequent and treatable metabolic defect, which can be diagnosed by detection of phenylpropionylglycine in urine after an oral load of phenylpropionic acid. We studied the determination of phenylpropionylglycine in urine by isocratic ion-exclusion chromatography on a cation-exchange column using water-sulphuric acid (pH values between 2 and 4) as mobile phase. Phenylpropionylglycine, phenylpropionic acid and hippuric acid exhibited high retention factors with only a slight decline at increasing solvent pH. This resulted in a good separation from interfering substances after direct injection of urine. We hypothesize that pi-pi interactions between the aromatic carbonic acids and the ion-exchange resin are responsible for the strong retention on the stationary phase. We conclude that, even in asymptomatic patients, determination of phenylpropionylglycine in urine after a phenylpropionic acid load by ion-exclusion chromatography is a rapid and reliable diagnostic tool for the detection of medium-chain acyl-CoA dehydrogenase deficiency.
authors.affiliation: Department of Clinical Chemistry and Biochemistry, Childrens Hospital, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Flath
authors.forename: B
authors.initials: B
authors.lastname: Rolinski
authors.forename: A A
authors.initials: AA
authors.lastname: Roscher
mesh_terms: D042964:Acyl-CoA Dehydrogenase; D044944:Acyl-CoA Dehydrogenases / Q000172:deficiency*; D002851:Chromatography, High Pressure Liquid; D005998:Glycine / Q000031:analogs & derivatives* / Q000652:urine; D006626:Hippurates / Q000032:analysis; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010666:Phenylpropionates / Q000032:analysis; D012680:Sensitivity and Specificity
chemical_list: D006626:Hippurates; D010666:Phenylpropionates; C057466:3-phenylpropionylglycine; C035253:3-phenylpropionic acid; D044944:Acyl-CoA Dehydrogenases; D042964:Acyl-CoA Dehydrogenase; C030514:hippuric acid; D005998:Glycine