Rapid and specific cyclosporine assay for the du pont aca® discrete clinical analyzer performed directly on whole blood

A rapid, sensitive, and specific enzyme immunometric assay for cyclosporine in whole blood has been developed for the aca® analyzer, using a monoclonal antibody from Sandoz, Ltd. Between‐run CVs ranged from 6.5 to 7.6% for samples containing between 60 and 400 ng/mL cyclosporine. Sensitivity was better than 25 ng/mL in the assay, which has an effective upper range of greater than 600 ng/mL. Two correlation studies compared cyclosporine values from the Du Pont method to those determined by HPLC procedures in three hospital laboratories. The results from a total of 120 whole blood samples with CsA between 20 and 800 ng/mL showed excellent correlation between the methodologies. HPLC and Du Pont CsA values from 10 day serial studies also correlated well for samples from a kidney, kidney‐pancreas, heart, and two liver transplant patients. We conclude that the Du Pont CSA assay provides accurate and reproducible results in a convenient format in less than 30 minutes.