What is Hematuria ?
Hematuria is defined as the abnormal presence of red blood cells (RBCs) or gross blood in the urine. If only the clinician can see the red blood cells under the microscope while the urine appears grossly clear it is called microscopic hematuria. If the patient can notice a change in color of the urine with the naked eye – either red , dark red, or dark, or notices blood clots, it is called gross hematuria. It is important to note that both gross and microscopic hematuria can indicate serious medical conditions.
In other words, . although both microscopic and gross hematuria can signal a serious medical condition, unexplained gross hematuia is often more concerning to the patient and the clinician.
Several conditions can cause hematuria, most of them are not serious. For example, vigorous exercise or even sexual intercourse may cause hematuria that goes away in 24 hours. Many people have microscopic hematuria without any other related problems. Often, despite a thorough evaluation, no specific cause can be found for the presence of red blood cells in the urine. But because hematuria may be the result of a cancer, a tumor, or other serious medical problem, a doctor should be consulted.
How to Evaluate Blood in the Urine ?
To find the cause of hematuria, or to rule out certain causes, the doctor may order a series of tests, including urinalysis, blood tests, kidney imaging studies, and cystoscopic examination. A cystoscope can be used to look, examine, and take pictures of the inside of the urinary bladder. A cystoscope is a tiny lighted lens with a camera at the end of a thin tube, which is inserted through the urethra. A cystoscope may provide a better view of a tumor or bladder stone than can be seen in an urinary tract imaging study. A cystoscopy is the only reliable test to evaluate the urinary bladder in cases of hematuria. According to the established guidelines of the Ameican Urologic Association (AUA), no other test can be substituted for a cystoscopy when evaluating blood in the urine .Therefore, a cystoscopy performed by a urologist is imperative to complete the hematuria evaluation.
Urinalysis is the examination of urine for various cells and chemicals. In addition to finding red blood cells, the doctor may find white blood cells that signal a urinary tract infection or casts, which are groups of cells molded together in the shape of the kidneys’ tiny filtering tubes,that signal kidney disease. Excessive protein in the urine also signals kidney disease. Blood tests may reveal kidney disease if the blood contains high levels of wastes ( Urea Nitrogen ) that the kidneys are supposed to remove. Blood tests may also provide a general idea od the kidney function ( creatinine, estimated glomerular filtration rate eGFR , etc ). In general, impaired kidney function diseases are best evaluated and treated by nephrologists ,instead of a urologist.
Kidney imaging studies include renal ultrasound, computerized tomography (CT) scan, or intravenous pyelogram (IVP). An IVP or CT Urogram is an x ray of the urinary tract obtained with intravenous contrast material ( Iodine ) . While renal simple cysts are frequently noted on kidney imaging studies, they typically do not cause hematuria and do not require any treatment. However complex kidney cysts should be further investigated for the possibility of kidney cancer. Kidney imaging studies with Iodine are best to detect kidney cancers and other serious urinary tract pathology. Imaging studies may reveal findings which can explain the hematuria such as a kidney or bladder cancer, a benign tumor of the urinary tract , a kidney or bladder stone, an enlarged prostate, or other blockage to the normal flow of urine.
It is important to note that cigarette smoking significantly increases the chance of developing bladder and urothelial cancers. This is another reason to avoid cigarette smoking.
Treatment for hematuria depends on the cause. After a very thorough evaluation, if no serious condition is causing the hematuria, no treatment is necessary and the patient can be reassured. If the hematuria is persisting after an initial evaluation , a repeat work up and further testing can be ordered.
The main message remains. The presence of red blood cells or gross blood in the urine may indicate a serious medical condition. It should never be ignored by the patient or the clinician. A thorough evaluation is the only way to determine the possible cause.