Hematuria is a clinical term referring to the presence of blood, specifically red blood cells, in the urine. Whether this blood is visible only under a microscope or present in quantities sufficient to be seen with the naked eye, hematuria is a sign that something is causing abnormal bleeding in the patient's genitourinary tract. The source of the bleeding can be located anywhere along this tract: the kidneys, the ureters (the tubes running from the kidneys to the bladder), the prostate gland (in men), the bladder or the urethra (the tube that carries urine from the bladder out of the body).
The bleeding may happen only once or it may be recurrent. It may or may not be accompanied by pain or discomfort during urination, and it can indicate different problems in men than in women. The cause may be as routine as an infection or as serious as cancer. Whatever the circumstances, hematuria should be regarded as a danger signal demanding immediate attention. Only a thorough physical examination and medical evaluation can interpret its meaning, determine its cause, or provide the patient with facts needed to make informed decisions about its treatment.
There are two basic types of hematuria.
In many cases, the appearance of blood in the urine, whether gross or microscopic, may be the patient's only outward symptom. Such cases are called asymptomatic. Others may be accompanied by a variety of symptoms ranging from a need to urinate frequently, to a consistent, suddenly occurring sensation of urinary urgency, to pain in the flank or side, or pain during urination (dysuria). Some cases, particularly those associated with kidney and urinary tract infections, may be accompanied by a fever.
A small number of asymptomatic people experience microscopic hematuria with no discernible cause. These so-called idiopathic cases are typical of individuals who for some unknown reason normally excrete a higher proportion of RBCs.
Interestingly, some cases that initially present the appearance of gross hematuria turn out to non-blood related. This condition, called pseudohematuria, usually is the result of ingested substances that impart a red color to the urine. Excessive consumption of beets or berries, food coloring, certain laxatives and pain medications all can result in a pink or reddish cast to the urine. Like idiopathic hematuria, however, a diagnosis of pseudohematuria can only be accurately made after thorough examination and testing. Persons who notice a change in the color of their urine should always consult their urologist or primary care physician immediately and never assume the condition is benign.
Hematuria may result from a great variety of causes. Not all are life-threatening, and some are more serious than others. All require professional medical evaluation and attention, however. The most common causes are:
In its less common forms, blood in the urine is sometimes experienced by joggers and long-distance runners ("jogger's hematuria"), a condition brought on by the repeated jarring of parts of the bladder. It also can be caused by a variety of rare diseases and genetic disorders, such as sickle cell disease (also called sickle cell anemia, a hereditary condition often associated with persons of African-American descent), lupus (also called lupus erythmatosus, a chronic disease of the skin, connective tissue, spleen, liver and other organs) and Von Hippel-Lindau syndrome (a rare genetic disease that causes multiple tumors of the brain, spine, eyes, adrenal glands, pancreas, inner ear, testicles and kidneys).
In evaluating hematuria, particularly gross hematuria, many doctors initially try to narrow the range of possible causes through a process of classifying the stage at which the bleeding occurs during urination (voiding). While classification is not definitive, it often provides a useful indicator for further examination and testing.
Hematuria-associated symptoms also can suggest the site and/or cause of bleeding:
After an initial evaluation, a thorough workup of the patient usually follows. In this the physician typically makes detailed inquiries about the patient's personal and family medical history. Personal questions will focus on a patient's urinary habits, recent illnesses, injuries and infections, history of kidney stones, recent and past drug use, drinking and smoking, and possible exposure to toxic substances dating back 25 years or more. Inquiries into one's family history can be made to look for possible inherited predispositions to renal stone disease, sickle cell disease, von Hippel-Lindau Syndrome and other genetic factors.
This process is followed by a thorough physical examination, with particular emphasis on the urinary tract, abdomen, pelvis, genitals and rectum. The extremities and joints also are examined carefully for abnormalities that typically indicate the presence of different kidney-related disorders.
Regardless of the findings of these inquiries and exams, the physician also will want to perform various analyses of the patient's urine and blood, and possibly one or more diagnostic tests.
In cases of suspected microscopic hematuria, a dipstick test usually will be performed. This is a simple test performed in the doctor's office in which a sample of the patient's midstream urine is applied to a special chemically treated strip. Agents impregnated on the strip will change color in the presence of even microscopic amounts of blood. The relative intensity of the color change indicates the amount of blood present.
A positive dipstick test usually is followed by a microscopic examination of the patient's urine, which might indicate the presence of a tumor by detecting the presence of cancer cells (urine cytology). A urine culture may be grown from the sample to check for various infections. Similar examinations of a 24-hour collection of the patient's urine also may performed, and a blood chemistry workup may be prescribed.
Patients whose gross or microscopic hematuria cannot be positively ascribed to an identifiable cause may undergo a cystoscopic examination. The usual procedure employed is called cystourethroscopy, an in-office or hospital test in which a small rigid or flexible fiber-optic instrument in inserted through the urethra under local anesthesia. Through it the physician can visually inspect the urethra, bladder and/or prostate. The exam takes about 10 minutes. Some patients experience minor, short-term discomfort with urination or slight spotting of blood for a day or two after cystoscopy. A warm bath may relieve this irritation, and antibiotics may be prescribed to ward off any possible infection.
Another useful diagnostic test used to determine the cause of hematuria is the IVP or intravenous pyelogram. This is a special X-ray procedure in which a colorless dye containing iodine is injected into a vein in the patient's arm. The dye collects in the urinary system and provides enhanced contrast for a series of X-rays taken over a 30-minute period. This gives the doctor or technician a better image of the kidneys, ureters and bladder and can disclose stones, tumors, blockages or other problems that may cause the bleeding. At the end of the procedure, the patient may be asked to go to the bathroom and empty his or her bladder completely, after which a final X-ray will be taken.
Patients who have had a prior allergic reaction to intravenous dye or shellfish should tell their doctor before undergoing an IVP so that necessary precautions can be taken.
Depending on the results of these procedures and evaluations, particularly if the physician has unresolved questions about the possible cause of a patient's hematuria, he or she may recommend additional tests of the urinary tract. These may include an ultrasound test--- an imaging procedure which uses sound waves projected into the body to create a visual image on a monitor --- or a computer-assisted tomography (CT or CAT) scan --- a procedure which creates a series of cross-sectional X-ray images.
Ultimately, the purpose of these examinations, tests and evaluations is to determine the cause and location of a patient's hematuria. In many cases, no specific cause can be ascribed. This is good, because such a finding indicates the bleeding probably is not caused by stones, cancer or other life-threatening diseases. Eliminating such diagnoses narrows the field of possibilities to a variety of conditions that may correct themselves or be idiopathic. In such cases the patient often is referred back to his or her primary physician for blood tests to check kidney function, blood pressure monitoring and regular periodic checkups. Men over 50 with no clear differential diagnosis should have a yearly PSA (Prostate Specific Antigen) test to screen for prostate cancer. Where a specific diagnosis can be made, treatment may range from simple antibiotic therapy, in the case of infection, to surgery, depending on the source of the bleeding.
An exhaustive discussion of specific treatments associated with differential diagnoses of hematuria cannot be offered here. Treatment is tailored to cause, and there simply are too many potential causes --- each drawing upon the detailed results of specific clinical tests, diagnostic evaluations and the physician's observation of patient symtoms --- to cover thoroughly and authoritatively in the context of this section.
Those seeking this level of specificity are advised to access the other sections of this Website featured under "Conditions." These are devoted to specific health problems associated with the primary organs dealt with in the practice of urology. Elsewhere, readers should research the great body of primary texts and medical literature on urology, nephrology and oncology available in their local public, college or medical library.
Persons seeking information concerning their own symptoms ideally should see their urologist or primary care physician. The "I Have A Symptom" section of "UrologyForum" at this website may provide them with useful preliminary information, and provide the basis for a more informed discussion with their urologist or family physician..
Hematuria may result from a broad spectrum of causes that range from non-life-threatening to profoundly serious. Regardless of when or how hematuria appears, it should never be ignored. The patient should regard it as a warning sign and consult his or her primary physician or urologist at the first possible opportunity.