RESUMEN
An immunoassay of sirolimus based on the microparticle enzyme immunoassay (MEIA) principle was evaluated on 105 whole blood samples (EDTA) drawn from a population of renal (n = 38) and hepatic or heart (n = 3) transplant patients. Each blood sample was analyzed simultaneously by MEIA and by a liquid chromatography mass spectrometry (LC-MS) method. The statistical analysis according to Passing-Bablok (x= LCMS, y= mean of two measurements of the same samples on IMx) produced the following results: Spearman r value = 0.9651, y(MEIA) = 0.99x (LCMS) - 0.26 microg/l. The analytical performance of the MEIA method showed a CV < or = 10% and a lower limit of quantification of 1.5 microg/l, which are acceptable for routine clinical monitoring. In conclusion, the MEIA method has shown robust, stable and reproducible features with an excellent correlation with the LC-MS method.