what causes occult blood in urine?!

Best Answer - Chosen by Voters

Occult blood is blood that is not visible. In the urine it means there are red blood cells
present. The reason may be minor or serious. It could be a sign of infection.
Some medications may cause it. It may be a sign of serious kidney problems.
If found in the urine there no doubt would be further testing unless the cause is
known already.

Kidney infection,stones or bladder problems.