Efficacy and Safety of Rituximab Versus Mycophenolate Mofetil in Children With Steroid-dependent Nephrotic Syndrome

Inclusion Criteria: * Children with a definite diagnosis of SDNS are included in the study during relapse treatment. * Age 3-16 years. * Steroid dependent dose≤0.3mg/kg/day. * Cumulative steroid use for ≥6 months. * Ability to swallow tablet. * Guardians understand the characteristics and personal consequences of clinical trial. * Guardians willing to give informed written consent. Exclusion Criteria: * Diagnosis of secondary NS, such as secondary to lupus nephritis, hepatitis B-related nephritis, purpura nephritis, etc. * Anti-neutrophil cytoplasmic antibodies(ANCA) positive or complement C3 level decreased. * Diagnosis of hereditary nephrotic syndrome. * Full dose of prednisone (2mg/kg/day, maximum 60mg) are used for 14 days after relapse and urine protein don't turn negative. * Estimated glomerular filtration rate (eGFR) \<90mL/min per 1.73m\^2 at study entry. * Those who with a known allergy to Mycophenolate Mofetil and their excipients or to Rituximab and its excipients. * Those who refuse to participate in the trial. * Those who participate other clinical trials. * Those who with positive HBV serological markers (HBsAg or/and HBeAg or/and HBcAb), HCV positive patients or patients with abnormal liver function (ALT,AST,or bilirubin\>2 or more times the upper limit of the normal range and persistently elevated for 2 weeks). * Severe leukopenia (white blood cells\<3.0×10\^9), severe anemia (hemoglobin\<90g/l), and thrombocytopenia (platelets\<100×10\^9) at study entry. *…