Renal biopsy findings and followup of renal function in rheumatoid arthritis patients treated with cyclosporin A - An update from the International Kidney Biopsy Registry

Objective. To review data from the International Kidney Biopsy Registry, which describes the occurrence of cyclosporin A (CSA)-induced nephropathy, and to discuss the potential risk factors for its development. Methods. The report examines data on a total of 60 first and 14 second renal biopsies performed in rheumatoid arthritis (RA) patients treated with CSA for up to 87 months. Results. Five of the 60 patients with RA included in the Biopsy Registry had findings consistent with CSA-induced nephropathy at first biopsy. One further patient had such findings at second biopsy. Of the 22 patients who started CSA at dosages <4 mg/kg/day and subsequently received dosages no higher than 5 mg/kg/day, none developed CSA-induced nephropathy. Continuous assessment of renal function did not show any evidence of deterioration over time in patients maintained on low-dose CSA. Conclusion. The data indicate that in RA patients being treated according to current dosing recommendations, the risk of developing CSA-induced nephropathy is low.