Response to cyclosporine in steroid-resistant nephrotic syndrome: discontinuation is possible

Background Steroid-resistant nephrotic syndrome (SRNS) is still regarded as a serious disease although treatment with cyclosporine (CSA) has improved outcome. However, the duration of treatment in responders is unclear, and treatment of patients with genetic causes is a matter of debate. Methods Thirty-six patients with SRNS were studied retrospectively. Median age at presentation was 3.2 (range, 0.06–15.0) and median follow-up 15.5 years (range, 1.8–27.7), respectively; 23 (64 %) had focal segmental glomerulosclerosis (FSGS) on biopsy. In 33/36 patients (92 %), genetic testing was performed for at least three most common genes known to be mutated in SRNS. Results Nineteen patients (53 %), especially those with minimal change nephrotic syndrome (MCNS) at initial biopsy ( p