Abstract: Objective:To observe the clinical efficacy and safety of tacrolimus(TAC) combined with low dose of corticosteroids in the treatment of the children with refractory nephrotic syndrome(RNS),and to investigate the effect of diltiazem on the blood concentration of TAC. Methods:A total of 16 hospitalized children with refractory nephrotic syndrome(RNS)were selected.All patients were treated with TAC(0.10-0.15 mg·kg^-1·d^-1)combined with low dose of corticosteroids(l.0-2.0 mg·kg^-1·d^-1).The concentrations of TAC of the children during the treatment process were monitored.The 24 h urine protein quantitative(UP),plasma albumin (Alb),creatinine and other 6 indexes were recorded before treatment and 2,4,8,12 and 24 weeks after treatment. Results:In 16 cases,9 cases were completely relieved,5 cases were partially relieved,and 2 cases were invalid;the total efficiency was 94%.The 24 h UP of 16 children at 24 weeks after treatment was significantly decreased compared with before treatment(Z=-3.516,P<0.01);the plasma Alb level of the children was significantly increased compared with before treatment(Z=-3.516,P<0.01).The total cholesterol and triglyceride levels at 2 weeks after treatment were decreased significantly compared with before treatment(Z=-2.223,P<0.05;Z=-3.464,P<0.01).Eight patients had low blood concentration of TAC,and it was increased to an effective concentration after treated with diltiazem.In the course of treatment,creatinine,urea nitrogen and other indexes of the patients were fluctuated in a normal range. Conclusion:TAC combined with low dose of corticosteroids for treatment of RNS is safe and effective,and diltiazem can effectively increase the blood concentration of TAC.

Key words: tacrolimus, refractory nephrotic syndrome, prednisone aectate, diltiazem, children