The causes of occult blood in urine (+-) are as follows: 1. Women can have occult blood in urine (+-) a few days before and after menstruation, which is normal and does not require treatment. 2. Occult glomerulonephritis, if the patient has occult glomerulonephritis, the urine routine can show occult blood in urine (+-), if the patient has no symptoms and other laboratory tests are normal, there is no need for treatment. If the patient has urethritis, cystitis and other inflammatory diseases, the urine routine can have urine occult blood (+-), then the patient also has symptoms such as urinary frequency, urinary urgency, urinary pain, etc. The treatment at this time is to give antibacterial anti-inflammatory treatment.