Cyclosporine monitoring in patients with renal, cardiac and bone marrow transplants: A comparison between clone enzyme donor immunoassay and fluorescence polarization immunoassay methods.

In the present study a new method for selectively determining parent cyclosporine in whole blood, a clone enzyme donor immunoassay (CEDIA; Boehringer Mannheim), was compared with a fluorescence polarization immunoassay (FPIA; TDxAbbott). A total of 429 samples were collected, comprising 371 renal, 34 cardiac, 14 bone marrow and 10 corneal transplant recipients. Regression equations in 429 samples is CEDIA cyclosporine (ng/mL) = 0.999 x FPIA (ng/mL) + 1.684, (r=0.997). The linearity analysis was done from 0 – 1,000 ng/mL, which gave a good analytical range of between 15-600 ng/mL. The new CEDIA method also has within-rin CV = 1.77 – 3.69 percent which is better than the FPIA method (2.20 – 6.10 percent). The advantages of the new CEDIA method are the lower cost of the reagents and the fact that there is no need to purchase a new automated clinical chemistry analyser since it can be applied to routine chemistry instruments immediately after the reagents become available to the laboratory.