Clinically, when doctors suggest that kidney disease patients need to undergo renal puncture biopsy, most of the patients refuse. Analyzing the patients’ psychology, there are two reasons: first, fear, because renal puncture biopsy is an invasive test, patients are afraid of pain, but also worried that the puncture will aggravate the damage to the kidneys, and will leave after-effects after the operation. The second is the psychology of indifference, thinking that kidney disease can’t be cured anyway, and the puncture is not helpful to the treatment, so why bother to take a needle again? In fact, the above idea is wrong and partial. The reason is that although patients with renal disease can manifest proteinuria, hematuria, or edema, the cause of the disease is very complex, the nature of the lesion is also diverse, and the prognosis is also very different. For example, patients with clinical manifestation of proteinuria, the pathology can be focal nephritis, thylakoid proliferative nephritis, focal segmental glomerulosclerosis, membranous nephropathy, membranoproliferative nephritis, IgA nephropathy, or diabetic nephropathy, lupus nephritis, renal amyloidosis, or other renal disorders, in which each of them has different treatment options and prognosis. On the other hand, the histopathologic changes of the same kidney disease are not consistent at different stages of the disease, such as lupus nephritis with five pathological types, which can undergo pathological transformation due to the effect of treatment or the development of the disease itself; the same IgA nephropathy, however, can be manifested pathologically as changes in almost all renal pathologies. Therefore, it is very important to understand the histopathological changes of the kidney for clinicians to judge the condition, treat the disease and judge the prognosis. The clinical significance of renal biopsy is as follows: 1. Renal biopsy can enable most patients to obtain a correct diagnosis, and can also correct the clinical diagnosis. 2. 2, through the kidney biopsy can correctly guide the clinical treatment and monitor the progress of the disease, can avoid a series of complications brought about by blind treatment, such as most of the patients with membranoproliferative nephritis, tiny lesions can achieve the effect of clinical cure by using hormone therapy, while membranous nephropathy, membranoproliferative nephritis and focal segmental sclerosing nephritis are insensitive to hormone therapy; lupus nephritis need to determine whether to need hormone shock and hormone shock based on the pathological changes of the kidney; lupus nephritis need to determine whether to need hormone shock and hormone shock based on the pathological changes of the kidney. Lupus nephritis needs to be determined according to the pathology of the kidneys to determine the need for hormonal shock and immunosuppressive drugs and other treatments; the cause of acute renal failure is more complex, renal biopsy can help to determine whether it is mainly glomerular or tubulointerstitial pathology, so as to adopt a targeted treatment plan; renal biopsy of renal transplantation patients will help to diagnose whether it is the rejection of the kidney or the kidney damage caused by drugs. 3, through the kidney biopsy can be more accurate evaluation of the prognosis of patients with kidney disease, kidney biopsy can determine the degree of renal histopathological damage, but also can be found in the kidney disease is in the active lesion stage or has developed to irreversible chronic lesion stage. Therefore, patients with renal disease, especially adults, need to consider renal puncture biopsy when the cause, treatment and prognosis are not clear and there are no contraindications. Specific indications are as follows: 1, acute nephritis syndrome: clinical manifestations of acute nephritis syndrome patients in the rapid deterioration of renal function, suspected of acute glomerulonephritis should be actively create the conditions for early renal biopsy, the early diagnosis and treatment of such patients is directly related to the clinical prognosis. In addition, patients with acute nephritis syndrome should also undergo renal biopsy when their condition does not improve after 2-3 months of treatment for acute glomerulonephritis. 2, nephrotic syndrome: adult primary nephrotic syndrome before treatment, it is best to carry out a renal biopsy, in order to clarify the type of renal pathology, to determine the treatment plan, to avoid blind application of high-dose hormones or immunosuppressants caused by side effects. Children with nephrotic syndrome can be treated with regular hormone therapy for 8 weeks first, and consider kidney biopsy when it is not effective. 3, asymptomatic proteinuria: proteinuria persists more than 1g/24h when the reason is not clear, renal biopsy can help correct diagnosis. 4, asymptomatic hematuria: the emergence of metachronous erythrocyturia clinical diagnosis is unclear, or hematuria recurring more than 6 months, renal biopsy helps diagnosis. 5.Systemic systemic diseases: such as systemic lupus erythematosus, allergic purpura, systemic small vessel vasculitis, a variety of anomalous proteolytic nephropathies (including multiple myeloma, kappa light chain disease, amyloidosis and mixed cryoglobulinemia), and other diseases that involve the kidney to a very different extent and the prognosis of the disease, the renal biopsy should be carried out as soon as possible. 6, diabetic nephropathy: about 1/3 of diabetic patients with kidney damage may be non-diabetic nephropathy, such as type 2 diabetes mellitus combined with membranous nephropathy, IgA nephropathy or crescentic nephritis. Therefore, type 2 diabetes mellitus with large amount of proteinuria, associated with hematuria, or rapid development of nephropathy need to perform renal biopsy. 7.Transplantation kidney: early biopsy after kidney transplantation can clarify whether it is acute tubular necrosis, acute rejection, anti-rejection drugs (neurocalcitonin inhibitor) nephrotoxicity and other causes of transplantation renal insufficiency. In the late stage of renal transplantation, the biopsy of transplanted kidney in case of renal insufficiency can clarify whether it is chronic rejection, nephrotoxicity of anti-rejection drugs, recurrence of nephropathy, polyomavirus infection or new glomerular disease.8. Acute Renal Failure: acute renal failure caused by pre-renal oliguria and urinary tract obstruction can be diagnosed without renal biopsy. In most cases, acute tubular necrosis can be diagnosed correctly according to the clinic, and renal biopsy may be helpful in determining the prognosis. Therefore, renal biopsy in patients with acute renal failure is only indicated for those with glomerular lesions, interstitial lesions, small-vessel renal lesions, or those with doubtful diagnosis, or those with acute tubular necrosis of more than 4 weeks’ duration in which renal function is not restored. Contraindications to renal biopsy: 1, absolute contraindications: ① obvious bleeding tendency; ② severe hypertension; ③ mental illness or do not cooperate with the operation; ④ isolated kidney. 2, relative contraindications: ① active pyelonephritis, renal tuberculosis, pyelonephrosis or pus, renal abscess or perinephric abscess; ② renal tumor or renal aneurysm; ③ polycystic kidneys or renal cysts; ④ kidney position is too high (deep inhalation of renal hypophysis does not reach the lower part of the twelve ribs) or wandering kidneys; ⑤ chronic renal failure; ⑥ obesity; ⑦ severe ascites; ⑧ cardiac failure, severe anemia, hypovolemia, pregnancy, or old age. (h) Cardiac failure, severe anemia, hypovolemia, pregnancy, or old age. Renal puncture biopsy can reveal the truth of the disease, and it is the most direct and objective method to make a clear diagnosis. So, does performing kidney puncture have any effect on the body or not? In fact, renal puncture is the application of a special puncture needle in ultrasound-guided positioning, to obtain a small amount of renal pathological tissue, one side of the kidney has one million glomeruli, renal puncture to take out such a small section of tissue, at most, contains 10-20 glomeruli, compared with the whole kidney can be said to be a drop in the bucket. The patient is placed in the prone position during the operation, and the doctor uses local anesthesia to complete the operation in just a few minutes. After the operation, the patient can get out of bed and move freely on the second day. In general, the risk of complications from renal puncture can be minimized with strict control of the indications and procedures, as long as the patient is well matched. The common complications of renal biopsy are: 1, hematuria: postoperative urinalysis increased red blood cell count, accounting for 80%-90% of puncture cases, without special treatment; naked eye hematuria most often occurs on the day of renal biopsy, especially when the first postoperative urination, but also can be delayed until 1-2 weeks after the operation occurs, mostly related to excessive activity. 2, perirenal hematoma: renal biopsy complication of perirenal hematoma is more common, the incidence of 34-60%, the vast majority of patients have no clinical symptoms, some patients may be manifested as lumbar pain, abdominal distension, abdominal pain, abdominal discomfort and abdominal discomfort radiating to the lumbar ribcage or groin distension, with nausea, vomiting. Perinephric hematoma generally does not require special treatment, bed rest is the main, can be appropriate to apply some symptomatic measures, hematoma is mostly absorbed within 2-4 weeks. 3.Infection: low incidence, such as fever, severe back pain, high white blood cells need antibiotic treatment.