Microscopic Hematuria: What Causes It?

When you go to see your doctor for a routine physical, he or she may have asked you to give a urine sample. By using a special dipstick, your doctor can quickly check the pH of your urine as well as check for the presence of certain components including blood. It’s quite possible for you to have blood in your urine and have your urine look completely normal in appearance. When blood in the urine is detectable only by dipstick or by looking under a microscope, it’s known as microscopic hematuria. If you have microscopic blood in the urine or microscopic hematuria, should you be concerned? 

The Causes and Significance of Microscopic Hematuria

A variety of conditions can cause traces of blood including kidney disease, but the most common is the presence of a urinary tract infection or a kidney stone. Generally, when you have one of these two conditions as a cause of microscopic hematuria, you’ll have other symptoms including burning with urination, more frequent urination, and abdominal discomfort in the case of a urinary tract infection.

If you have a kidney stone, you’ll characteristically have intermittent back pain and flank which may be associated with nausea and vomiting. If a urinary tract infection is causing the symptom of microscopic hematuria, there will usually also be white blood cells in the urine which your doctor can detect by dipstick and by looking under the microscope.

In some cases, you can have a urinary tract infection with minimal symptoms. For this reason, your doctor may choose to give you antibiotics to see if it causes the microscopic blood in the urine to clear. If not, he may recommend that you further tests to look inside your urinary tract for the presence of stones or tumors.

Exercise: A Cause of Microscopic Hematuria?

Sometimes microscopic blood in the urine can be caused by exercising vigorously before giving the urine sample. This can sometimes occur in kids who play sports. Usually, the traces of blood in the urine disappear after three days of rest. If not, your doctor may want to do further tests.

Other Causes of Microscopic Hematuria

There are also some hereditary conditions that can cause microscopic blood in the urine, including sickle cell disease and polycystic kidney disease. If either of these conditions is suspected, your doctor would want to do more testing.

Although microscopic hematuria is usually caused by a urinary tract infection or kidney stone, especially in a younger person, it’s important to follow up with your doctor to find out the cause. This is a symptom you don’t want to ignore.