I had a routine yearly check up and large blood cells were found during routine urine test (dipstick). The blood is not visible. When recheck after one week, moderate blood cells were found. All blood work is normal except Vitamin D is low (17). I have slight left flank pain from time to time (for a year or two) and no other symptoms. No pain upon urination, sexual intercourse, exercise, etc. No changes in appearance of urine, etc. Now what? I do NOT want to have a cystoscope! But would be willing to explore other options...