Brief Answer:
Needs to see the urologist again

Detailed Answer:
Hello, I'm Dr. Branch, thanks for using Ask a Doctor. With his history of having "grit" in his urine, that may make it more likely that this is also related to small stones that otherwise aren't causing any symptoms. However, at his age, bladder cancer is a common cause of blood in the urine, and so especially if it has been a couple of years since he has been evaluated, I would recommend going back to his urologist to get evaluated. They will want to take a look at the urine to confirm whether the bleeding is coming from the kidneys or from somewhere else in the urinary tract, and will likely need a cystoscopy to look at the bladder and make sure the bleeding isn't coming from there.

This would not necessarily be urgent, but if he begins to have trouble with passing urine, he will likely need to go to the ER to get this addressed quickly. Otherwise, I would recommend he stay well hydrated to help keep the urine flowing and to try to prevent blood clots from forming that could cause an obstruction.

I hope that helps, please let me know if you have any questions about any of that, and I would be glad to discuss it with you further.

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