Hematuria is a common disease in urology, which can be divided into gross hematuria and microscopic hematuria (it is meaningful to check more than three red blood cells in urine by microscope). Patients often ignore intermittent hematuria, and when gross hematuria stops, patients are often in no hurry to see a doctor, thus delaying treatment. Moreover, the color of hematuria is often not completely consistent with the severity of the disease. There are five common causes of hematuria: coagulation disorder, urinary tract infection, urinary calculi, urinary tract injury and urinary tract tumor. The following focuses on the characteristics of hematuria caused by urinary system diseases. 1 Hematologic diseases are the most common causes of systemic bleeding tendency, such as leukemia, hemophilia, aplastic anemia and thrombocytopenic purpura, which can cause hematuria. Taking anticoagulant drugs sometimes causes hematuria. 2 hematuria caused by urinary system infection (including pyelonephritis, cystitis, urethritis, etc. ) often accompanied by frequent urination, urgency and dysuria (bladder irritation sign), acute pyelonephritis accompanied by high fever, chills and low back pain. In men, if accompanied by terminal hematuria and acute urinary retention, acute prostatitis should be considered. There are a lot of white blood cells besides red blood cells in the urine test. After anti-infection treatment, hematuria is generally relieved. In addition, bladder perfusion with anticancer drugs can cause hemorrhagic cystitis. Radiotherapy can also cause radiation cystitis. 3 When urinary calculi occur, in addition to hematuria, the clinical manifestation can be severe renal colic. Urinary calculi are mainly diagnosed by B ultrasound or X-ray examination. After the stones are effectively treated, the general hematuria disappears. All urinary system injuries have a history of injury, which must be dealt with in time to make clear the location and degree of injury. Urinary tumors are more common in the elderly, and the characteristics of hematuria are as follows: ① Intermittent attacks (hematuria can disappear without treatment); ② The whole process (with the whole process of urination); ③ Painless (the most common is bladder tumor). The degree of hematuria is not completely consistent with the size, number and malignant degree of tumor. It is possible that the tumor is small, but there is a lot of bleeding; Or the tumor is big and there is little bleeding.