Routine urine occult blood (+-) indicates weakly positive urine occult blood. If there is urinary occult blood, it means that there are red blood cells in the urine, but (+-) suggests that the number of red blood cells is relatively small, about 3. The main things to consider when there is occult blood (+-) in the urine routine are, 1. The presence of specimen contamination, suggesting that the patient review the urine routine again in a few days. If you can urine occult blood show negative results, there is no need to worry too much. 2, kidney disease, urine occult blood, such as patients with nephritis, there will be urine occult blood. 3, urinary tract infection, may also be combined with frequent urination, urinary urgency, painful urination and positive results of urine leukocytes. The last common causes may be tumors of the urinary tract or systemic diseases, such as systemic lupus erythematosus nephritis and thrombocytopenic purpura nephritis, which can lead to urinary occult blood (+-).