Study on Precision Dosing Strategies of Anti-infective Agents in the Very Early Stage of Kidney Transplantation

Inclusion Criteria: 1. Aged \>= 18 years old; 2. Patients receiving kidney transplantation within 0-5 days postoperatively; 3. Clinically planned administration of anti-infective agents for perioperative prophylaxis, empirical therapy or confirmed infection treatment, with an anticipated treatment duration of no less than 5 days; 4. Written informed consent obtained from the subject or legal surrogate; 5. Indwelling urinary catheter retained for at least 48 hours postoperatively to facilitate early urine sample collection; 6. Patients anticipated to be free of dialysis requirement with urine output or early graft functional recovery at enrollment. Exclusion Criteria: 1. Previous kidney transplantation or combined multi-organ transplantation 2. Patients requiring continuous renal replacement therapy in the early postoperative period 3. Severe hepatic dysfunction, defined as Child-Pugh class C, or ALT/AST \> 5 times the upper limit of normal accompanied by markedly elevated bilirubin 4. Early postoperative use of ECMO, plasmapheresis or other extracorporeal therapies that substantially alter drug clearance 5. Pregnancy or lactation 6. Subjects judged inappropriate for enrollment by investigators, including those with unfeasible sampling, extremely short expected survival, severe missing clinical data, etc.