Seeing blood in your urine can be frightening, even for the most macho of men. When this occurs, or when your doctor tells you that your urine test showed red blood cells, it's time for a medical evaluation. Although the results are often reassuring, blood in the urine — called hematuria — is a warning sign that you should never ignore.
If your urine looks pink or red, it's called visible hematuria. Your urine can look normal but still have red blood cells in it. This is called invisible or microscopic hematuria. It is usually detected during a routine urine analysis.
Hematuria may or may not have symptoms. Here are some symptoms that suggest particular causes of hematuria:
Although it's important to look for these clues, they're usually missing. Most hematuria is invisible and has no symptoms.
Major causes of urinary bleeding in men include:
Because microscopic hematuria is usually discovered during a routine urine test, it's a good idea to re-test the urine. If two or more tests show red blood cells, it's time to do a more in-depth study of the kidneys.
The first step is to take a closer look at the urine itself. If the urine has even small amounts of protein (microalbuminuria), or if the appearance of the urine cells suggests they come from the kidney's glomeruli (the tiny blood vessels that filter fluid from the blood), the doctor should focus on the possibility of kidney disease. This means first measuring levels of creatinine — a waste product in the blood — to look at kidney function.
Other tests for kidney disease may include blood tests for inflammation, ultrasound imaging to measure kidney size and 24-hour urine collections. The doctor may also check for various causes of kidney disease that don't cause bleeding, such as diabetes and hypertension. Depending on the results, the doctor may recommend seeing a kidney specialist, who may recommend a kidney biopsy. Although some people with this type of microscopic hematuria turn out to have serious kidney disease, most have mild problems, such as IgA nephropathy (deposits of an immune protein on the glomeruli).
You'll probably breathe a sigh of relief if your doctor reports that you don't have kidney disease. But that still leaves you without a diagnosis. This usually means that you'll need more tests to check for other causes of your hematuria.
If you see blood in your urine, it won't be hard to convince you to have tests to find out why you are bleeding. Among other things, you'll want to be sure you don't have a tumor somewhere in your urinary tract. It's a legitimate concern, particularly for smokers and people over age 50. (A study of 948 patients with visible hematuria found that nearly a quarter had urinary tract malignancies.)
But other conditions may be responsible. (See Causes of Urinary Bleeding in Men.) and thorough testing may not pinpoint the cause in 53% of patients with visible hematuria and in 68% of patients with microscopic hematuria. Still, all patients with blood in the urine need careful evaluation.
Your doctor will tailor your testing to your personal and family history, your risk factors and your symptoms. Here is a list of tests that may be helpful:
Both men and women can experience urinary bleeding. But the problem is more common in men.
Although urinary tract infections can cause hematuria — and are more common in women — many of the other leading causes of urinary bleeding are more common in men: kidney stones, bladder cancer and kidney cancer. (Prostate disease is obviously confined to men.)
Men have a tendency to ignore symptoms (the “Ostrich Syndrome”) or to grit their teeth and try to tough out problems (the “John Wayne Syndrome”). In the case of urinary bleeding, though, ignorance may be blissful in the short run but it's hazardous in the long run.
It's true that many cases of hematuria are never diagnosed, and many others are caused by non-cancer conditions such as infections, kidney stones, BPH and even exercise. But since bladder cancer, kidney cancer and prostate cancer are also on the list of possible causes, every man with blood in the urine, whether it's visible or not, should see his doctor for a thorough evaluation. It's the manly thing to do.
Blood in the urine always requires a complete medical and urological evaluation. But often that evaluation fails to pinpoint the cause. What then? Most people remain well, but some don't. So while vigilance is in order and a periodic urinalysis may be helpful, it's probably not necessary to repeat the full battery of tests unless bleeding recurs or other problems develop.
Harvey B. Simon, M.D. is an Associate Professor of Medicine at Harvard Medical School and a member of the Health Sciences Technology Faculty at Massachusetts Institute of Technology. He is the founding editor of the Harvard Men's Health Watch newsletter and author of six consumer health books, including The Harvard Medical School Guide to Men's Health (Simon and Schuster, 2002) and The No Sweat Exercise Plan, Lose Weight, Get Healthy and Live Longer (McGraw-Hill, 2006). Dr. Simon practices at the Massachusetts General Hospital; he received the London Prize for Excellence in Teaching from Harvard and MIT.