title: Validation of an LC-MS/MS Method for Urinary Lactulose and Mannitol Quantification: Results in Patients with Irritable Bowel Syndrome.
abstract: Aim. Lactulose/mannitol ratio is used to assess intestinal barrier function. Aim of this work was to develop a robust and rapid method for the analysis of lactulose and mannitol in urine by liquid chromatography coupled to tandem mass spectrometry. Lactulose/mannitol ratio has been measured in pediatric patients suffering from irritable bowel syndrome.Methods. Calibration curves and raffinose, used as internal standard, were prepared in water : acetonitrile 20 : 80. FiftyμL of urine sample was added to 450μL of internal standard solution. The chromatographic separation was performed using a Luna NH2column operating at a flow rate of 200μL/min and eluted with a linear gradient from 20% to 80% water in acetonitrile. Total run time is 9 minutes. The mass spectrometry operates in electrospray negative mode. Method was fully validated according to European Medicine Agency guidelines.Results and Conclusions. Linearity ranged from 10 to 1000 mg/L for mannitol and 2.5 to 1000 mg/L for lactulose. Imprecision in intra- and interassay was lower than 15% for both analytes. Accuracy was higher than 85%. Lactulose/mannitol ratio in pediatric patients is significantly higher than that measured in controls. The presented method, rapid and sensitive, is suitable in a clinical laboratory.
authors.affiliation: UOC Laboratorio Analisi I, Fondazione Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Jacopo
authors.initials: J
authors.lastname: Gervasoni
authors.affiliation: UOC Laboratorio Analisi I, Fondazione Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Arcangelo
authors.initials: A
authors.lastname: Schiattarella
authors.affiliation: Pediatria, Fondazione Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Giorgio
authors.affiliation: UOC Laboratorio Analisi I, Fondazione Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Aniello
authors.initials: A
authors.lastname: Primiano
authors.affiliation: Pediatria, Fondazione Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Consuelo
authors.initials: C
authors.lastname: Russo
authors.affiliation: UOC di Medicina Interna Gastroenterologia e Malattie del Fegato, Fondazione Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Tesori
authors.affiliation: UOC di Medicina Interna Gastroenterologia e Malattie del Fegato, Fondazione Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Franco
authors.identifier: 0000-0001-8334-7541
authors.initials: F
authors.lastname: Scaldaferri
authors.affiliation: UOC Laboratorio Analisi I, Fondazione Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Urbani
authors.affiliation: UOC Laboratorio Analisi I, Fondazione Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Zuppi
authors.affiliation: UOC Laboratorio Analisi I, Fondazione Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Silvia
authors.identifier: 0000-0002-7955-8810
authors.initials: S
authors.lastname: Persichilli
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D002853:Chromatography, Liquid / Q000379:methods; D005260:Female; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000652:urine*; D007792:Lactulose / Q000652:urine*; D008297:Male; D008353:Mannitol / Q000652:urine*; D013058:Mass Spectrometry / Q000379:methods; D016482:Urinalysis / Q000379:methods*
chemical_list: D008353:Mannitol; D007792:Lactulose