Hematuria includes microscopic hematuria and visual hematuria. Microscopic hematuria refers to normal-colored urine with an abnormal increase of red blood cells in the urine by microscopic examination. The standard examination method of microscopic hematuria is: take 10ml of clean and fresh middle urine, centrifuge for 5 minutes at 1500 rpm, the remaining sediment 0.2ml, mix and aspirate 20μl of the sediment, drop on a slide, cover with an 18mm×18m After covering with an 18mm×18m coverslip, the urine was examined with a 10 × 40 (× 400) times light microscope, and the result was diagnosed as hematuria if there were ≥3 red blood cells per high-powered field of view. Non-centrifuged urine with more than 1 red blood cell per high-powered field of view, or a 1-hour urine red blood cell count of more than 100,000, or a 12-hour urine sediment count of more than 500,000, can also be diagnosed as hematuria. When more than 1 ml of blood per liter of urine is mixed, the urine may appear red or washboard-like, or there may be blood clots in the urine, which is called sarcohematuria.