What causes a dark colored blood when wiping? After using the bathroom there is a dark colored blood on the tissue, my back hurts on the mid-lower left side. What can be the cause of this? Sn… this has been going on for about a week, there isn't any bloo

You . You may be dealing with a urinary tract infection, kidney stones, or even a kidney infection (pyelonephritis). You should see a medical professional right away for evaluation, testing, and treatment. Best of luck.