The significance and timing of the need for renal puncture biopsy for simple hematuria: This problem is often encountered in clinical practice: a routine urine test reveals positive urine occult blood (and sometimes high urine red blood cell count), but otherwise normal. The patient is very worried after seeing the test results. At this point, some doctors may suggest the patient to do renal puncture. In fact, this kind of phenomenon is more common in clinical practice. In fact, what we need to do is: 1, first of all, to exclude possible factors that interfere with the test results, such as menstruation, taking certain drugs, etc. 2, to figure out whether it is hematuria: because urinary occult blood only indicates the presence of hemoglobin or myoglobin in the urine. To confirm that it is hematuria it must be confirmed that the urine is positive for occult blood while the urine red blood cell count is also high. 3, If it is determined to be hematuria, then the next step is to understand the origin of the blood: this can be done by performing a morphological observation check of the red blood cells in the urine. Generally speaking, the proportion of abnormal morphology of red blood cells in urine over 75% is considered to be blood originating from the kidneys, which means that there is a problem with the kidneys. 4.If it is determined that there is a kidney problem, is it necessary to do a kidney puncture? There are two views on this issue: do it when necessary. Which is the right approach? It is difficult to answer this question. In general, I suggest the patient to do this: 1, first of all, review the urine red blood cells, while excluding the factors that may cause errors. 2. Check the 24-hour urine protein quantification. 3, according to the above results then decide whether to immediately kidney puncture or follow-up observation.