[Effect of cyclosporin A on renal function in patients with glomerulonephritis]

Abstract

Background and objective: Cyclosporin A ( CsA) plays a confounding part in the treatment of nephrotic syndrome. Renal hemodynamics and glomerular permselectivity were investigated in patients with glomerulonephritis to analyse the antiproteinuric action of CsA and to differentiate between nephrotoxic and immunosuppressive effects.

Methods: We studied 19 patients with nephrotic syndrome after 6 months of treatment with CsA (membranous glomerulonephritis-MGN, n = 10; focal segmental sclerosing glomerulonephritis - FSGN, n = 5; minimal changes glomerulonephritis - MCGN, n = 4). Patients were studied three times within 3 weeks with (A) and without (B) CsA treatment (A-B-A'). Blood pressure, creatinine, proteinuria, C(In), C(PAH), C(Dex) were measured (analysis according to the model of Deen et al., Am J Physiol. 1985; 249 : 374).

Results: GFR (C (In)) increased significantly after withdrawal of CsA from 54 +/- 7.3 to 64 +/- 8.5 ml/min (p < 0.01). Proteinuria increased after withdrawal of cyclosporin (B) between 21 % (MGN) and 45 % (FSGN). After withdrawal of CsA (B) there was no change of FC(dex) in patients with MGN and FSGN. Withdrawal of CsA in patients with MCGN induced a significant decrease in glomerular selectivity in the high molecular range.

Conclusion: These data demonstrate that CsA is able to induce even in the short term a significant increase in glomerular permselectivity in MCGN. The acute effects on GFR predominantly determined the acute antiproteinuric effects in patients with MGN and FSGN.