[Treatment of idiopathic nephrotic syndrome with cyclosporine A]

Cyclosporin-A (Cy-A) is a new drug used in the treatment of idiopathic nephrotic syndrome (INS) over the past few years. The treatment is based on the two postulates; first, that INS is presumably a disorder of T lymphocytes, and second, that Cy-A exerts its immunomodulatory effect on T cell immunity. The paper first gives evidence why in the current nephrology the three histologic variants, i.e. minimal changes, focal glomerular sclerosis and diffuse mesangial hypercellularity are termed idiopathic nephrotic syndrome, and review of immunopathogenesis of INS, which might be a rational use of Cy-A as therapeutic modality. Recent data concerning the treatment of INS with Ca-A have shown that Cy-A might be an alternative drug for corticosteroid sensitive patients, but who are either frequent relapsers or drug-dependent. However, Cy-A maintain remission during administration only. It could be used to overcome side effects of corticosteroid therapy, which is of particular interest in children with growth retardation. Treatment of patients resistant to classic immunomodulatory therapy (corticosteroids, cyclophosphamide, chlorambucil) was beneficial only in 22% of cases. In these patients, especially if their glomerular filtration rate is reduced, Cy-A is potentially nephrotoxic and may lead to rapid deterioration of renal function. Long-term administration of Cy-A requires regular screening for nephrotoxicity by laboratory tests and renal biopsy every 6-12 months.