Two-year cyclosporin treatment in children with steroid-dependent nephrotic syndrome

Byline: Yuji Inoue (1), Kazumoto Iijima (1), Hajime Nakamura (1), N. Yoshikawa (2) Keywords: Key wordsaChronic nephrotoxicity; Cyclosporin treatment; Minimal change nephrotic syndrome Abstract: aWe describe a prospective study of 2-year moderate-dose cyclosporin (CS) treatment in 13 children with steroid-dependent minimal change nephrotic syndrome (MCNS). CS treatment was commenced at 100--150amg/m.sup.2 per day after remission was attained with prednisolone therapy, was adjusted to a target trough level of 100ang/ml, and was administered for 2 years. The number of relapses during CS treatment significantly decreased compared with before CS treatment, all patients were able to discontinue prednisolone therapy, and steroid toxicity was reduced 54% of patients remained in remission during CS treatment. Renal biopsies performed before CS treatment all showed MCNS without tubulointerstitial lesions. Creatinine clearance and urinary [beta].sub.2-microglobulin levels during CS treatment were normal in all patients, but renal biopsies performed after CS treatment revealed chronic CS nephrotoxicity in 7 patients. Clinical data, including CS dose and CS trough blood levels, were not significantly different between patients with and without nephrotoxicity. In conclusion, 2-year moderate-dose CS treatment in children with steroid-dependent MCNS is effective in preventing relapse and decreasing steroid toxicity. This treatment can, however, result in a high incidence of chronic nephrotoxicity. Renal function is not a reliable indicator of chronic CS nephrotoxicity. Renal biopsy is therefore necessary to monitor chronic CS nephrotoxicity. Author Affiliation: (1) Department of Pediatrics, Kobe University School of Medicine, Kobe, Japan, JP (2) Faculty of Health Science, Kobe University School of Medicine, Tomogaoka 7-10-2, Suma-Ku, Kobe, Japan 654 Tel.: +81-78-796-4515, Fax: +81-78-796-4509, JP Article note: Received: 4 March 1998 / Revised: 28 April 1998 / Accepted: 25 June 1998