2. An enlarged prostate
If a man discovers blood in his urine, it could be the result of an infected prostate. The prostate gland sits just below the bladder and surrounds a portion of the bladder. It can enlarge as men reach middle age, and if it does, it can compress the urethra and partially block the flow of urine.
When this happens, blood cells can pass into the urine, which can lead to hematuria. An enlarged prostate may sound concerning, and it some cases, it is; however, it is usually caused by a condition known as benign prostatic hyperplasia or BPH. To treat BPH, surgery may be necessary in order to either reduce the size of the prostate or remove it completely.