A Cochrane review included 19 studies with a total of 820 (773 evaluated) children with idiopathic steroid resistant nephrotic syndrome (SRNS). Cyclosporine when compared with placebo or no treatment significantly increased the number of children who achieved complete remission (RR 7.66, 95% CI 1.06 to 55.34; 3 studies, n=49). Calcineurin inhibitors (cyclosporin or tacrolimus) significantly increased the number with complete or partial remission compared with IV cyclophosphamide (RR 1.98, 95% CI 1.25 to 3.13; 2 studies, n=156). There was no significant differences in the number who achieved complete remission between tacrolimus versus cyclosporin (RR 0.86, 95% CI 0.44 to 1.66; 1 study, n=41), cyclosporin versus mycophenolate mofetil plus dexamethasone (RR 2.14, 95% CI 0.87 to 5.24; 1 study, n=138), oral cyclophosphamide with prednisone versus prednisone alone (RR 1.06, 95% CI 0.61 to 1.87; 2 studies, n=91), IV versus oral cyclophosphamide (RR 3.13, 95% CI 0.81 to 12.06; 1 study, n=11), IV cyclophosphamide versus oral cyclophosphamide plus IV dexamethasone (RR 1.13, 95% CI 0.65 to 1.96; 1 study, n=49), and azathioprine with prednisone versus prednisone alone (RR 0.94, 95% CI 0.15 to 5.84; 1 study, n=31). One study found no significant differences between 3 agents (cyclophosphamide, mycophenolate mofetil, leflunomide) used in combination with tacrolimus and prednisone. One study (n=31) found no significant difference in the percentage reduction in proteinuria (-12, 95% CI -73 to 110) between rituximab with cyclosporin/prednisolone and cyclosporin/prednisolone alone. Two studies reported ACEi significantly reduced proteinuria.
Comment: The quality of evidence is downgraded by study limitations (lack of blinding), and by imprecise results (few patients and outcome events).