Hematuria is the presence of blood, more specifically red blood cells, in the urine. It can be either macroscopic (seen with naked eyes, Pic. 1), or microscopic (detectable only by microscopic examination of the urine, Pic. 2). Macroscopic hematuria is a medical condition that constitutes the 4% to 20% of all urological visits. It has a broad spectrum of causes, from being idiopathic (without a known cause) or just caused by strenuous physical activity, to kidney stones, trauma to the urinary tract or tumours arising from the organs of the urinary tract. The individual conditions may differ in terms of symptoms accompanying the hematuria. If it is accompanied by a pain in the side or even colicky, extremely painful seizures, it is likely to be caused by kidney stones. Painless hematuria may be the first sign of urinary bladder cancer, or certain other tumours. If the red blood cells appear together with white blood cells in the urine, the patient is likely to have an urinary tract infection. All of these conditions can manifest as macroscopic hematuria, but in less severe lesion of the urinary tract, the same condition may only cause microscopic hematuria.
Hematuria may be associated with several diseases including:
Prostate cancer
Prostate cancer is the second most lethal type of cancer in male patients. The highest incidence (60–70%) of prostate cancer is seen in men who are in their seventh decade of life. Patients are typically asymptomatic due to early detection by prostate-specific antigen (PSA) testing and digital rectal exams (DRE) but may present with outflow obstruction, hematuria, lower leg edema, and bone pain. Hematuria usually appears when the tumor grows into the wall of the prostatic part of the urethra and erodes its lining, allowing for leakage of blood into the urine.
Benign prostatic hyperplasia
Benign prostatic hyperplasia is a noncancerous increase in size of the prostate. When sufficiently large, the nodules push on and narrow the urethra resulting in an increased resistance to flow of urine from the bladder. This is commonly referred to as "obstruction", although the urethral lumen is no less patent, only compressed. This obstruction often leads to incomplete emptying of the bladder, which may in turn give rise to stones in the bladder or a bladder infection. Both these condition can clinically manifest with hematuria.
