The objective of this clinical trial was to understand whether FMT is effective in treating steroid-dependent/steroid-resistant nephrotic syndrome in children. It will also learn about the safety of FMT. The main question it was designed to answer was: Did FMT reduce participants '24-hour urine protein content? What medical problems did participants experience while using FMT? The researchers will compare FMT treatment with and without FMT on top of conventional treatment to see if FMT is effective in treating steroid-dependent/steroid-resistant nephrotic syndrome in children. Participants will receive 2 FMT treatments, 1 endoscopic injection under anesthesia, 1 oral fecal bacteria transplantation capsule intake, and follow-up visits (weeks 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, and 48) every 4 weeks from the beginning of medication to our renal specialist clinic for drug efficacy evaluation and safety testing. Blood and fecal samples were collected to determine the effects of fecal bacterial transplantation on intestinal flora, fecal metabolomics, and intestinal mucosal permeability.

Inclusion Criteria:

• Age 2-18 years, steroid-dependent/steroid-resistant nephrotic syndrome, regardless of gender, with SDNS at steroid-dependent doses less than 0.5 mg/kg.d

Exclusion Criteria:

• Those with concurrent infections or diseases of other organ systems, and those with abnormal renal function.