There is no obvious harm in high red blood cells in urine, but the diseases that cause high red blood cells in urine can lead to certain harm to the human body, which requires further examination to clarify these diseases and then make targeted treatment, the possible hazards are as follows: 1, urinary system stones, stones can lead to high red blood cells in urine appear elevated, so that the stones will cause acute pain, accompanied by frequent urination, urinary urgency, if left untreated for a long time, the stones can lead to hydronephrosis and renal insufficiency. 2. Acute infection of the urinary system can lead to elevated red blood cells in the urine, which can lead to erosion, congestion and rupture of the mucosa of the urinary tract, causing bleeding and pain, and if left untreated, can lead to increased body temperature and even bacteremia. 3, Tumors of the urinary system can lead to high red blood cells, tumors can lead to destruction of the bladder, which can cause distant metastases, cause massive bleeding, and even cause failure of important organs, etc.