Matthijs Oyaert1, Nele Peersman2, Davy Kieffer3, Kathleen Deiteren4, Anne Smits5, Karel Allegaert5, Isabel Spriet6, Johan Van Eldere3, Jan Verhaegen3, Pieter Vermeersch7, Steven Pauwels7. 1. University Hospitals Leuven, Department of Laboratory Medicine, B-3000 Leuven, Belgium. Electronic address: matthijsoyaert@telenet.be. 2. University Hospitals Leuven, Department of Laboratory Medicine, B-3000 Leuven, Belgium. 3. University Hospitals Leuven, Department of Laboratory Medicine, B-3000 Leuven, Belgium; KU Leuven - University of Leuven, Department of Microbiology and Immunology, B-3000 Leuven, Belgium. 4. Antwerp University Hospital, Department of Laboratory Medicine, B-2650 Edegem, Belgium. 5. KU Leuven - University of Leuven, Department of Development and Regeneration, B-3000 Leuven, Belgium; University Hospitals Leuven, Neonatal Intensive Care Unit, B-3000 Leuven, Belgium. 6. KU Leuven - University of Leuven, Department of Clinical Pharmacology and Pharmacotherapy, B-3000 Leuven, Belgium; University Hospitals Leuven, Pharmacy Department, B-3000 Leuven, Belgium. 7. University Hospitals Leuven, Department of Laboratory Medicine, B-3000 Leuven, Belgium; KU Leuven - University of Leuven, Department of Cardiovascular Sciences, B-3000 Leuven, Belgium.
Abstract
BACKGROUND: Accurate quantification of vancomycin in plasma is important for adequate dose-adjustment. As literature suggests between-method differences, our first objective was to develop a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for total vancomycin in human plasma and to compare frequently used immunoassays with this method. Secondly, we investigated the clinical impact of between-method quantification differences. METHODS: For LC-MS/MS, lithium heparin plasma was extracted by adding a precipitation reagent containing the internal standard (vancomycin-des-leucine). Analysis was performed on an Acquity TQD mass spectrometer equipped with an Acquity UPLC 2795 separations module. Our method was analytically validated and compared with four frequently used immunoassays from four different manufacturers. Vancomycin concentrations were clinically classified as toxic, therapeutic and sub-therapeutic. Clinical discordance was calculated using LC-MS/MS as a reference. RESULTS: A novel LC-MS/MS method using protein precipitation as sole pretreatment and an analysis time of 5.0 min was developed. The assay had a total imprecision of 2.6-8.5%, a limit of quantification of 0.3 mg/L and an accuracy ranging from 101.4 to 111.2%. Using LC-MS/MS as reference, three immunoassays showed a mean proportional difference within 10% and one showed a substantial mean proportional difference of >20%. Clinical discordant interpretation of the obtained concentrations ranged from 6.1 to 22.2%. CONCLUSIONS: We developed a novel LC-MS/MS method for rapid analysis of total vancomycin concentrations in human plasma. Correlation of the method with immunoassays showed a mean proportional difference >20% for one of the assays, causing discordant clinical interpretation in more than 1 out of 5 samples.
BACKGROUND: Accurate quantification of vancomycin in plasma is important for adequate dose-adjustment. As literature suggests between-method differences, our first objective was to develop a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for total vancomycin in human plasma and to compare frequently used immunoassays with this method. Secondly, we investigated the clinical impact of between-method quantification differences. METHODS: For LC-MS/MS, lithium heparin plasma was extracted by adding a precipitation reagent containing the internal standard (vancomycin-des-leucine). Analysis was performed on an Acquity TQD mass spectrometer equipped with an Acquity UPLC 2795 separations module. Our method was analytically validated and compared with four frequently used immunoassays from four different manufacturers. Vancomycin concentrations were clinically classified as toxic, therapeutic and sub-therapeutic. Clinical discordance was calculated using LC-MS/MS as a reference. RESULTS: A novel LC-MS/MS method using protein precipitation as sole pretreatment and an analysis time of 5.0 min was developed. The assay had a total imprecision of 2.6-8.5%, a limit of quantification of 0.3 mg/L and an accuracy ranging from 101.4 to 111.2%. Using LC-MS/MS as reference, three immunoassays showed a mean proportional difference within 10% and one showed a substantial mean proportional difference of >20%. Clinical discordant interpretation of the obtained concentrations ranged from 6.1 to 22.2%. CONCLUSIONS: We developed a novel LC-MS/MS method for rapid analysis of total vancomycin concentrations in human plasma. Correlation of the method with immunoassays showed a mean proportional difference >20% for one of the assays, causing discordant clinical interpretation in more than 1 out of 5 samples.
Authors: Philippe Dauphin-Ducharme; Kyungae Yang; Netzahualcóyotl Arroyo-Currás; Kyle L Ploense; Yameng Zhang; Julian Gerson; Martin Kurnik; Tod E Kippin; Milan N Stojanovic; Kevin W Plaxco Journal: ACS Sens Date: 2019-10-15 Impact factor: 7.711
Authors: Janko Samardzic; Anne Smits; Isabel Spriet; Ivan Soldatovic; Andrew Atkinson; Milica Bajcetic; John N Van Den Anker; Karel Allegaert Journal: Biomed Res Int Date: 2016-08-21 Impact factor: 3.411
Authors: Samadhan B Patil; Rajai M Al-Jehani; Hashem Etayash; Valerian Turbe; Keren Jiang; Joe Bailey; Walid Al-Akkad; Rania Soudy; Kamaljit Kaur; Rachel A McKendry; Thomas Thundat; Joseph W Ndieyira Journal: Commun Biol Date: 2018-10-24