title: Determination of mycophenolic acid plasma levels in renal transplant recipients co-administered sirolimus: comparison of an enzyme multiplied immunoassay technique (EMIT) and liquid chromatography-tandem mass spectrometry.
abstract: This study was designed to compare the enzyme multiplied immunoassay technique (EMIT) and a specific ;liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of mycophenolic acid (MPA) concentrations in plasma samples collected from renal transplant patients receiving mycophenolate mofetil in association with sirolimus and corticosteroids. Ten-point blood concentration-time profiles, between pre-dose (C0) and 9-hour post-dose, were obtained on day 7, day 14, months 1, 2, and 3 posttransplantation in 8 patients. MPA plasma concentrations were measured simultaneously with both EMIT and LC-MS/MS. Higher concentrations were obtained with EMIT. The mean (+/-SD) absolute difference was +0.84 +/- 1.93 mg/L, which corresponds to a significant overestimation of 18.7 +/- 2 6.8% with EMIT, with variations depending on the time elapsed since transplantation. An EMIT overestimation of 16.7 +/- 22.5% also was obtained for the MPA areas under the curve calculated using the trapezoidal rule.
authors.affiliation: Department of Pharmacology and Toxicology, Limoges University Hospital, Limoges, France.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Prémaud
authors.forename: Annick
authors.initials: A
authors.lastname: Rousseau
authors.forename: Nicolas
authors.initials: N
authors.lastname: Picard
authors.forename: Pierre
authors.initials: P
authors.lastname: Marquet
mesh_terms: D019540:Area Under Curve; D002853:Chromatography, Liquid / Q000379:methods*; D003404:Creatinine / Q000097:blood; D016903:Drug Monitoring / Q000379:methods; D004791:Enzyme Inhibitors / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use; D017248:Enzyme Multiplied Immunoassay Technique; D006084:Graft Rejection / Q000517:prevention & control; D006801:Humans; D016030:Kidney Transplantation; D013058:Mass Spectrometry / Q000379:methods*; D009173:Mycophenolic Acid / Q000097:blood* / Q000493:pharmacokinetics / Q000627:therapeutic use; D020123:Sirolimus / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use; D013997:Time Factors
chemical_list: D004791:Enzyme Inhibitors; D003404:Creatinine; D009173:Mycophenolic Acid; D020123:Sirolimus