Hi, @nbrud. Following up my posting above in August 2019, I hope my experience includes some comfort for you. First our differences. On my twice-a-year hematuria episodes, my urine turns light pink, not very dark. Nor have I had urinary tract infections. I had a large piece of prostate removed by a TURP procedure. My cystoscope results after that have been recorded regularly to ensure that the papillary tumors originally discovered have not returned. Finally that surgery was performed 12 years ago, but during the intervening period my only experiences have been regular cystoscope examinations and occasional hematuria. So your mystery and mine are similar in this respect: My urologists can't pinpoint where the blood is coming from, but advise that infection in the bladder and/or urinary tract often result in mild hematuria over time -- it could be leakage from some of the many blood vessels in the area. When I originally noticed it, I made it an issue for each of my visits with my urology team, who advised me not to worry unless the blood in the urine becomes "frank" -- undiluted and solid colored, hopefully red. So I have not worried, since my episodes have all been diluted blood. Adding to Amanda's question, how long have you been taking Bactrim? Could your hematuria be connected to Covid-19? Martin