Hello,
Microscopic hematuria can be due to urinary tract (bladder) infection, swelling
in the filtering system of the kidneys, stone
in bladder or
in a kidney,
blood disease, like sickle cell anemia, certain medicines and tumors in the urinary tract.
You should get done a cystoscopy. I also suggest you to get done an ultrasound abdomen to look for any kidney stone and blood tests for sickle cell anemia.