Evaluation of monoclonal/polyclonal ratio in kidney-transplanted patients treated with cyclosporine.

Fifty-seven kidney-transplanted outpatients, treated with cyclosporine alone or associated with azathioprine, prednisone, or methylprednisolone, were submitted to a monthly follow-up in order to determine cyclosporine blood levels and the monoclonal/polyclonal (M/P) ratio. Only methylprednisolone was able to modify the M/P ratio. This drug increased the M/P ratio, suggesting a cyclosporine metabolic inhibition. This effect disappeared in a few months in spite of the continuation of methylprednisolone treatment.