Many patients visit the hospital because of sudden onset of hematuria, and they are very afraid of bleeding in urine, so let us talk about some common causes of hematuria: Causes of urological diseases 1. Kidney stones and ureteral stones may scratch the epithelium of the urinary tract and cause hematuria during their downward movement. 3.Urological tumors: Painless hematuria often occurs in the renal pelvis, ureter and bladder tumors, which can often be detected by ultrasound and enhanced CT of the urinary tract. 4, trauma: bleeding caused by urinary tract injury due to violence, often combined with a history of trauma. 5, congenital anomalies: congenital polycystic kidney, nutcracker phenomenon, etc. Systemic diseases can also cause urinary bleeding 1, drug-related hematuria: commonly seen in elderly patients, bleeding caused by abnormal coagulation mechanisms due to the long-term use of large amounts of anticoagulant drugs, such patients often have a history of taking anticoagulant drugs. 2, bleeding disorders: often seen in thrombocytopenic purpura, hemophilia, leukemia, etc. 3, vascular disease: renal embolism, renal vein thrombosis, etc. 4, some other factors: such as physiological hematuria, radiation exposure, taking toxic drugs, and some endocrine metabolic diseases, etc. For the examination of the cause of hematuria, we need to take a detailed medical history after admission, perform urine three-cup test, urinary routine, as well as urinary ultrasound, urinary pathology examination, enhanced CT and cystoscopy of the urinary tract if necessary.