The main causes of increased red blood cells in urinalysis are infections of the urinary system, urinary stones and tumors of the urinary system. According to different causes, the harms mainly include urinary frequency and urgency, urinary pain, infection, renal hypoplasia and so on. 1. Urinary system infection caused by increased red blood cells: acute infection of the urinary system will lead to increased red blood cells in the urine test, the main hazards are urinary urgency, urinary pain, urinary frequency. In severe cases, it can also lead to urinary incontinence and urinary retention. 2. The harm of erythrocyte increase caused by urinary stones: stones in the urinary system will also lead to increased erythrocytes in the urine test. Urinary stones can damage the urethra leading to hematuria, while urinary stones can lead to obstruction of the urethra as well as infection. Long-term stimulation of urinary stones may lead to cancer in serious cases. 3. The danger of increased red blood cells caused by urinary system tumor: the tumor of urinary system will also lead to increased red blood cells in urine test. Its harm is mainly to cause patients’ renal function to decrease, which may cause metastasis, deterioration of condition or even death in the later stage. When there is an increase in red blood cells in urine test, you should go to the hospital in time, timely treatment, so as not to delay the condition.