By Andre Gilbert, MD
Blanchard Valley Urology Associates
Hematuria is a term used when there is an abnormal presence of blood in the urine. Two different forms of hematuria are gross hematuria (urine is red, identified by the naked eye) and microscopic hematuria (identified only by urine tests). It is also very important to pay attention if the hematuria is accompanied by symptoms such as burning sensation to urinate, urinary frequency (daytime or nighttime), urinary urgency, fever, lower abdominal pain and back pain. More concerning is when hematuria has no associated symptoms at all (painless gross hematuria).
Gross and microscopic hematuria can be seen in urinary tract infections, commonly associated with symptoms of urinary frequency and burning sensation to urinate. A patient with gross hematuria can have the false impression they are losing a significant amount of blood in the urine when realistically, a drop of blood mixed with urine turns all the urine red.
Many patients can present dark brown colored urine for different reasons. Dehydration during hot weather is often the most common cause. Morning urine can also be more concentrated and darker but is not to be confused with gross hematuria when the urine color is actually red. When a female patient suspects of gross hematuria, it is important to determine the source of the bleeding, since most sit down to void and the blood is noticed either on the toilet paper when wiping or in the toilet bowl. The bleeding can be coming from different sources besides the urine: vaginal source (menstrual period, gynecological pathology) or rectal source (hemorrhoids, gastrointestinal pathology).
The screening urine test done in most offices for hematuria relies on a unique strip dipped in the freshly collected urine (knows as “urine dipstick”). It can give the provider a hint of many conditions, including microscopic hematuria. Unfortunately, there is a high incidence of false-positive results (the strip shows blood in the urine but actually the urine is normal), so it is recommended to follow an abnormal urine dipstick with a formal microscopic urine analysis in the laboratory before the diagnosis of microscopic hematuria can be made. The reason for this precaution is that the workup for hematuria involves further urine tests, radiologic imaging studies and cystoscopy (looking inside the bladder), which are more invasive and may be avoided if the urine dipstick is falsely positive.
Gross hematuria almost always warrants evaluation. If painless gross hematuria, the hallmark of some tumors of the urinary tract (benign or malignant), a thorough work-up is recommended.
The U.S. Preventive Task Force and the American Urological Association discourage routine testing for hematuria to screen for bladder cancer in patients without symptoms.
It is important to know that cigarette smoking is the single most important risk factor for bladder cancer. According to the American Cancer Society, smokers are at least three times as likely to get bladder cancer as nonsmokers. Therefore, the increased risk of bladder cancer is yet another reason to stop smoking.
