The Efficacy and Safety of Dapagliflozin in the Treatment of Hereditary Kidney Disease With Proteinuria in Children

Inclusion Criteria: * Confirmed diagnosis of hereditary kidney disease (identification of pathogenic genes through molecular genetic testing; for Alport syndrome, molecular diagnosis is not necessarily required if diagnosed based on clinical and pathological findings; for those with a clear family history and a high clinical suspicion of hereditary kidney disease). * 24 - hour urinary protein level \> 0.2 g or urinary protein to creatinine ratio (UPCR) \> 0.2 mg/mg. * Calculate the estimated glomerular filtration rate (eGFR) using the Schwartz formula (36.5 \* height in cm / serum creatinine in μmol/L), with eGFR ≥ 60 ml/min/1.73 m². * Stable use of the basic treatment drug RAASi (including ACEI/ARB) for more than 4 weeks, and no dosage adjustment during the treatment period. * Willingness to sign the informed consent form. Exclusion Criteria:Exclusion applies if any of the following criteria are met: * Treatment with hormones/immunosuppressive agents within the previous 4 weeks. * Treatment with SGLT2 inhibitors within the previous 4 weeks. * Comorbid diabetes. * Uncontrolled urinary tract infection. * Evidence of urinary tract obstruction such as dysuria. * Blood pressure below the 5th percentile for the same gender, age, and height. * Organ transplantation. * Tumor. * Presence of any of the following definite evidence of liver disease: ALT/AST reaching 2 times the normal value, hepatic encephalopathy, esophageal varices, or portal shunt surgery. * Comorbid medical conditions that may affect drug absorption, distribution, metabolism, and excretion, including but not limited to any of the following: active inflammatory bowel disease within the past 6 months, history of major gastrointestinal surgery (such as gastrectomy, gastroenterostomy, intestinal resection), gastrointestinal ulcer, gastrointestinal or rectal bleeding within the past 6 months, pancreatic injury or pancreatitis within the past 6 months. * Subjects at risk of dehydration or volume depletion, which may affect drug efficacy or safety. * Participation in other drug trials within the previous 4 weeks. * Blood loss exceeding 400 ml within the previous 8 weeks. * Poor past medication compliance or unwillingness to complete the trial. * Any other medical conditions that may place the patient at a higher risk due to participation in this study.