In general, it is the nephrologist who cannot confirm the diagnosis of kidney disease through blood tests, urine tests for ultrasound and other examinations, or although the clinical diagnosis is confirmed but the severity of kidney damage is not clear, and this clear understanding of the condition determines whether the doctor will implement a special treatment plan, and the implementation of this plan directly affects the prognosis of the disease or not. At this point, the doctor will recommend that the child undergo a kidney puncture (pathological examination) with the aim of obtaining a pathological diagnosis of the kidney disease, which will guide the doctor in assessing the current condition, developing the most appropriate treatment plan, and predicting the likely outcome (prognosis) in the long term. It is generally accepted that the following conditions are indications for renal puncture: 1. acute renal failure with unclear causes and poor treatment results; 2. long-term proteinuria, hematuria and episodic carnitic hematuria with unknown causes; 3. refractory nephrotic syndrome (hormone resistance, hormone dependence and frequent relapses); 4. allergic purpura nephritis and lupus nephritis: severe conditions and poor treatment results.