Abstract: AIM: To observe the clinical efficacy and safety of small dose of tacrolimus (TAC) combined with hormone in the treatment of refractory nephrotic syndrome (RNS).METHODS: 20 cases of prospective study of refractory nephrotic syndrome patients, when the study began hormone dosage adjustment to 0.5 mg·kg^-1·d^-1, for 8 weeks and gradually reduced, while taking a low dose of TAC, according to TAC serum concentration and clinical efficacy of adjusting dosage, regular follow-up liver function, 24 hour urinary protein, blood plasma TAC concentration and other biochemical indexes, and record adverse reactions.RESULTS: After second weeks to reduce proteinuria patients, plasma albumin level began to be recovered, there was statistically significant difference (P<0.05) before and after. 20 patients had different degree of ease in small dose of TAC combined with corticosteroid therapy, 5 cases in remission stage drug reduction process, TAC to add weight to the original dose relieved in 2 cases, the other 3 cases without response, including 1 cases of death;In 2 cases of infection recurrence, TAC amount does not relieve, 13 patients in remission was 9 months, TAC dose reduction is still in follow-up.Complete remission rate was 75%, the mortality rate was 5%, the relapse rate was 20%.CONCLUSION: Low dose of TAC combined with hormone can make the refractory nephrotic syndrome patients were relieved quickly, recurrence and treatment effect is related to the pathologic type, the less adverse reaction, good safety, and provides a new method for the treatment.

Key words: refractory nephrotic syndrome, tacrolimus, plasma concentration