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WHAT IS HEMATURIA AND HOW IS IT DIAGNOSED? ? Hematuria refers to blood in the urine. In some cases, blood makes the urine turn an abnormal color, while, in other cases, the urine appears normal. Hematuria may therefore be grossly visible or only visualized upon microscopic examination of the urine.

Gross hematuria or discolored urine ? Gross hematuria is suspected because of the presence of urine that is red or brown. The color change does not usually reflect a large degree of blood loss, since very small amounts of blood in the urine can induce a visible color change.

Other reasons the urine may be discolored include, in women, blood that is actually coming from the vagina. If this is suspected, a urine specimen should be obtained after the woman has inserted a vaginal tampon and washed the genital area thoroughly. If blood remains in the specimen, it is likely to be from a urinary and not a vaginal source. The use of certain medicines and eating beets, and certain rare diseases, can also cause red or brown urine.

Microscopic hematuria ? Hematuria may be discovered by accident when blood is found on a test of the urine or a positive dipstick test on an analysis of the urine (urinalysis) done for other purposes, such as a screening test. Blood in the urine that cannot be seen without a microscope is called "microscopic hematuria."

TRANSIENT OR PERSISTENT HEMATURIA ? When hematuria is found, the doctor will want to know if it is present all the time (persistent hematuria), or represents a transient event (transient hematuria). Repeat urine specimens on several days may be needed to make this determination.

Once hematuria is discovered, establishing whether it is persistent or transient is an important part of the medical evaluation. Transient microscopic hematuria is a common problem in adults. This was shown in one study of 1000 young men who had yearly urinalyses between the ages of 18 and 33; hematuria was seen in 39 percent on at least one occasion and 16 percent on two or more occasions. No obvious etiology could be identified in the great majority of cases. By comparison, persistent hematuria is much more likely to be a symptom of an underlying disease (see next section).

WHAT CAUSES HEMATURIA? ? A number of different conditions can cause hematuria. Some of the most common are:

Other conditions or diseases can sometimes cause hematuria, such as vigorous exercise or trauma, and bleeding disorders related to disease or medications. As previously mentioned, no cause can be found for transient hematuria in many cases.

IS HEMATURIA DANGEROUS? ? Hematuria alone is rarely dangerous, since it does not reflect large amounts of blood loss. However, as noted above, some cases of hematuria are related to serious conditions, such as cancer. Any time persistent hematuria is found (or even transient or intermittent hematuria in men over the age of 50), it is important to find out why it has occurred.

HOW DOES THE DOCTOR FIND OUT WHAT IS CAUSING HEMATURIA? ? There are a number of tools the doctor may use to try and find out what is causing the hematuria. Not all are appropriate for every patient. Decisions about whether to perform various diagnostic tests are based on many factors such as the patient's history and age, and the preliminary findings from analysis of the urine.

History ? There are often clues from the patient's history that point to a specific diagnosis. For example, pain on urination might suggest bladder infection, while pain on one side of the lower back suggests a kidney stone. Doctors will consider the relevant history before deciding on what further tests, if any, are needed.

Analysis of urine ? Laboratory analysis of the various components of the urine give important clues as to the cause of hematuria. In some cases, repeated specimens over time may be needed.

Blood tests ? The doctor may order blood tests to look for evidence of kidney or other diseases that can cause hematuria.

Intravenous pyelogram ? An intravenous pyelogram (IVP) is a test in which dye is injected into a vein so that the kidneys, ureter, and bladder will appear on x-ray.

Kidney ultrasound ? Ultrasonography of the kidney provides another way to view the kidneys using sound waves instead of X-ray.

Cystoscopy ? In this surgical procedure, a small tube is inserted into the bladder by a urologist. The doctor can look through the tube to examine the bladder. If abnormal tissue is seen, a biopsy can be taken to determine the underlying cause.

Renal biopsy ? A small piece of tissue from the kidney is removed and is examined for signs of kidney disease.

WHAT IS THE TREATMENT FOR HEMATURIA? ? There is no specific treatment for the hematuria itself. Rather, treatment is aimed at the underlying cause.

WHERE TO GET MORE INFORMATION ? Your doctor is the best resource for finding out important information related to your particular case. Not all patients with hematuria are alike, and it is important that your situation is evaluated by someone who knows you as a whole person.