PATIENT CONDITION
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INTRODUCTION Hematuria is the presence of blood in the urine. The blood may be visible (referred to as gross hematuria), or detected by a urine microscopic examination (known as microscopic hematuria). Regardless of the presentation, hematuria is a sign that there is bleeding in the genitourinary system: the kidneys, ureters, bladder, prostate or urethra. When the finding is gross hematuria, the urine is typically pink, punch colored, blood red or dark brown. It may contain blood clots. Microscopic hematuria is defined as greater than three red cells under high power microscopic examination performed by a physician or laboratory. Blood in the urine may also be intermittent, meaning it could be present or absent from one examination to another. Nevertheless, the amount of blood in the urine does not indicate the seriousness of the problem and should always be investigated. Reddish urine that is not caused by blood is known as pseudohematuria. This can be caused by excessive ingestion of beets, berries, rhubarb, food coloring, some laxatives and some medications. It is always best to have your physician determine if reddish color is due to blood or other causes. Substances and Medications Affecting Urine Color(which can mimic hematuria)
The prevalence of microscopic hematuria has been reported to range from 10% to 20% in adult men and women. When it is identified further evaluation by a urologist is usually recommended. Risk factors for finding significant underlying renal or urologic disease in association with hematuria include: age greater than 40, tobacco use, excessive pain medication use (phenacetin), prior pelvic irradiation or chemotherapy, immunosuppression and exposure to occupational toxins such as certain dyes, benzene compounds and aromatic amines. Risk Factors for Urothelial Carcinoma (cancer of the inner lining of the urinary tract)
After a patient is determined to have hematuria by the primary care physician, additional studies may be obtained or the patient may be referred on to a urologist or nephrologist for further evaluation. At that point a fairly standard evaluation is recommended. A routine history will be obtained and physical examination performed. A urinalysis will be obtained by a midstream clean catch method. This method involves starting urination into the commode, and after several seconds, catching the urine stream in a cup, then finishing the last portion of the urination in the commode. Specimen collection by this method provides the best specimen for evaluation in men, but in women the specimen can often become contaminated with natural vaginal secretions during collection. When this is suspected by the urologist, a single catheterized specimen may be required. This involves passing a small tube into the women's urethra to drain the urine and eliminate any contamination. Once a satisfactory urine specimen is obtained it will be tested using a urine test strip or dipstick. These test strips consist of small pads impregnated with reagents on a plastic strip. When dipped into a urine specimen the test strips will change color determining the presence or absence of certain substances in the urine such as glucose, ketones, pH, specific gravity, urobilinogen, protein, bilirubin, nitrite and blood. If blood is found, the specimen of urine will be centrifuged, and the sediment obtained observed under the microscope specifically looking for red blood cells, white blood cells, casts, crystals and microorganisms.
In patients with suspected "benign" causes for hematuria such as menstruation, recent vigorous exercise, sexual activity, viral illness or minor trauma, a repeat urinalysis approximately 48 hours after cessation of the activity or illness is usually recommended. If microscopic hematuria persists further evaluation is indicated. In all cases of gross hematuria further evaluation is essential. Complete urologic evaluation includes radiologic imaging of the kidneys, urinary cytologic evaluation and cystoscopic examination. All three components are essential since no single study adequately evaluates the complete urinary tract. Cytologic examination is a specialized urine examination. In this study a urine specimen is collected and prepared, then sent to a cytologic laboratory for testing. Under the direction of a pathologist cells are collected from the urine, specially stained, and then examined under the microscope primarily looking for cell changes suspicious for urinary tract cancer. Recently, newer advances in testing have become available where cytologic examination may be substituted by urinary cancer marker testing. Which form of testing is determined by your urologist and availability of laboratory facilities. Radiologic imaging can be performed by a variety of techniques. The four most common tests used include Renal Ultrasound (US), Intravenous Urography (IVU or IVP), Computed Tomography Scan (CT Scan) or Magnetic Resonance Imaging (MRI). As with all tests there are specific advantages and disadvantages to each. Renal Ultrasound is a technique where high frequency sound waves are passed into the body and reflections of the sound waves can be displayed on a screen demonstrating the anatomy of various organs. Because of the location of the kidneys, they can be easily imaged using this technique. The technique has no associated risks and is painless to perform. The quality of the images, however occasionally limit the accuracy. Intravenous Urography formerly known as Intravenous Pyelography (IVP) has been the mainstay of evaluation of the urinary tract for decades. It is particularly useful for imaging the drainage system of the kidneys, ureters and bladder. It involves inserting an intravenous catheter into a vein and administering a contrast fluid which is excreted by the kidneys. Multiple abdominal x-ray films are taken to demonstrate the anatomy of the urinary tract. The venous catheter involves a slight amount of pain with insertion but is otherwise painless. The most significant limitation in its use is the risk associated with the contrast material, where severe allergic reactions may occur or damage to the kidney's function may occur. Computed tomography is becoming the new imaging technique of choice of the urinary tract. It is extremely accurate, especially for identification of urinary tract stones and tumors of the kidney. The patient is laid flat onto a special table which passes through a large "donut shaped" x-ray generator and detector. The x-ray images are fed into a computer and reformatted for interpretation. The technique can include use of contrast material to enhance images and improve the quality of the images. The technique is extremely fast and painless except for the insertion of a venous catheter. The CT not only images the urinary tract organs but all other abdominal and pelvic organs as well. Magnetic Resonance Imaging uses a technique where the molecules in the body are oriented by use of large magnets and detectors which can be fed into a computer and formatted onto computer screen as images. The patient is passed through a long narrow tube housing the magnets and detectors. The technique is excellent for certain urologic conditions, but not usually used as a primary evaluation of hematuria. It is painless and safe, however many patients feel the tube creates feelings of claustrophobia. In general, your urologist will make specific recommendations as to which test is preferred based on availability, detection rates, risks, side effects, renal function and other medical problems which may limit a particular studies' usefulness. Cystoscopy is an examination which involves viewing the urethra and urinary bladder with a specialized telescope. It is a common diagnostic procedure performed by urologists. The procedure can be performed with either a rigid cystoscope or a flexible telescope. The type of instrument used will be determined by your urologist, depending in part by the history and other studies obtained. The procedure is performed with either a local anesthetic or intravenous sedation. The local anesthetic consists gently injecting a "jellylike" solution into the urethra and allowing several minutes to elapse prior to introducing the cystoscope. Intravenous sedation consists of injecting anesthetic agents directly into a vein, producing sedation where the patient drifts off into a short sleep, experiencing minimal discomfort. Intravenous sedation is always administered under the direction of an Anesthesiologist. The principle advantage to intravenous sedation is that the urologist has more freedom to investigate and biopsy suspicious lesions, if indicated, with minimal discomfort to the patient. Cystoscopy can also be enhanced by injecting x-ray contrast into the ureters and renal collecting system and observing the anatomy with fluoroscopy. This technique is referred to as retrograde pyelography and particularly useful in patients allergic to intravenous contrast material.  Drawing of a cystoscope viewing the interior of a bladder. CAUSES OF HEMATURIA There are many causes for hematuria in adults. Many of the causes for hematuria are benign in nature and require no further treatment other than observation. Unfortunately, the primary purpose of an evaluation is to identify serious or life threatening causes of hematuria. The most concerning of these is urologic cancer. Studies indicate that 1% -3% of patients undergoing evaluation of microscopic hematuria are diagnosed with a urologic cancer. The diagnosis of urologic cancer in patients presenting with gross hematuria is substantially higher. The following listing describes potential causes of hematuria. Urologic Causes of Hematuria
If no serious urologic source for the hematuria is identified the prognosis is excellent. Although many of the patients have structural abnormalities in the renal filtering system they have a low risk of progressive renal disease. Nevertheless, it has been demonstrated that hematuria may precede the development of a urologic cancer by several years. Therefore, after an initial evaluation, follow up with an urologist is recommended 2-3 years. |