title: Reliability of mycophenolic acid monitoring by an enzyme multiplied immunoassay technique.
abstract: BACKGROUND
  For mycophenolic acid (MPA), substantial inter- and intra-individual variability and drug interactions have been observed and therapeutic drug monitoring is now recommended. In this study, a MPA commercial Enzyme Multiplied Immunoassay Technique (EMIT) was evaluated and compared with the HPLC-UV reference method which is easily practicable in a routine laboratory.
  
  
  METHODS
  Plasma samples (n = 117) were collected from adult renal graft patients treated by mycophenolate in combination with either cyclosporin A (CyA) (n = 32) or tacrolimus (n = 85).
  
  
  RESULTS
  Considering all samples, correlation was excellent (p < 0.0001). However, significant MPA overestimation was observed with EMIT in the early post-transplant period (30%, n = 32) or when combined with cyclosporin (45%).
  
  
  CONCLUSIONS
  In the early post-transplant period, or in cases where CyA is used in combination with MPA, the EMIT cannot be recommended. HPLC or LC/MS are here the method of choice.
authors.affiliation: Department of Clinical Chemistry, Hôpital Erasme, Brussels, Université Libre de Bruxelles, Belgium.
authors.forename: Delphine
authors.initials: D
authors.lastname: Martiny
authors.forename: Pascale
authors.initials: P
authors.lastname: Macours
authors.forename: Frédéric
authors.initials: F
authors.lastname: Cotton
authors.forename: Philippe
authors.initials: P
authors.lastname: Thiry
authors.forename: Béatrice
authors.initials: B
authors.lastname: Gulbis
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000097:blood* / Q000627:therapeutic use; D002851:Chromatography, High Pressure Liquid; D016572:Cyclosporine / Q000627:therapeutic use; D016903:Drug Monitoring / Q000379:methods*; D004359:Drug Therapy, Combination; D017248:Enzyme Multiplied Immunoassay Technique; D006084:Graft Rejection / Q000097:blood / Q000188:drug therapy / Q000517:prevention & control; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D016030:Kidney Transplantation; D008875:Middle Aged; D009173:Mycophenolic Acid / Q000097:blood* / Q000627:therapeutic use; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D016559:Tacrolimus / Q000627:therapeutic use; D014466:Ultraviolet Rays
chemical_list: D000903:Antibiotics, Antineoplastic; D007166:Immunosuppressive Agents; D016572:Cyclosporine; D009173:Mycophenolic Acid; D016559:Tacrolimus