title: Diagnosis of creatine metabolism disorders by determining creatine and guanidinoacetate in plasma and urine.
abstract: Creatine metabolism disorders include a creatine transporter deficiency, as well as, deficiencies of two enzymes involved in creatine synthesis, arginine-glycine amidinotransferase (AGAT) and guanidinoacetate methyltransferase (GAMT). Laboratory diagnosis of these disorders relies on the determination of creatine and guanidinoacetate in both plasma and urine. Here we describe a rapid HPLC/MS/MS method for these measurements using a normal phase HILIC column after analyte derivatization.
authors.affiliation: Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
authors.forename: Qin
authors.initials: Q
authors.lastname: Sun
authors.forename: William E
authors.initials: WE
authors.lastname: O'Brien
mesh_terms: D000579:Amidinotransferases / Q000172:deficiency; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003401:Creatine / Q000097:blood* / Q000652:urine*; D005998:Glycine / Q000031:analogs & derivatives* / Q000097:blood / Q000652:urine; D050937:Guanidinoacetate N-Methyltransferase / Q000172:deficiency; D006801:Humans; D008659:Metabolic Diseases / Q000097:blood / Q000175:diagnosis* / Q000652:urine; D053719:Tandem Mass Spectrometry
chemical_list: D050937:Guanidinoacetate N-Methyltransferase; D000579:Amidinotransferases; C020681:glycine amidinotransferase; C004946:glycocyamine; D003401:Creatine; D005998:Glycine