Vancomycin assay performance in patients with end-stage renal disease receiving hemodialysis

Study Objective. To compare the performance of polyclonal fluorescence pola rization immunoassay (pFPIA) with that of enzyme-multiplied immunoassay tec hnique (EMIT) in patients receiving vancomycin and hemodialysis. Setting. Outpatient hemodialysis center. Patients. Seven subjects with end-stage renal disease treated with hemodial ysis 3 times/week with a cellulose triacetate hemodialyzer. Intervention. Subjects received vancomycin 1000 mg intradialytically during the first study session and 750 mg every other hemodialysis session therea fter for 4 weeks. Measurements and Main Results. Blood samples were obtained throughout the s tudy and vancomycin serum concentrations were determined by pFPIA and EMIT. The mean +/- SD difference (estimate of bias) between assays was -1.10 +/- 1.35 mg/L. The limits of agreement (mean difference +/- 1.96 . SD) between them were -3.80-1.60 mg/L. Conclusion, Our data suggest that the manufacturer's changes in the vancomy cin pFPIA eliminated overestimation of drug concentrations in patients unde rgoing high-permeability hemodialysis.