When blood gets into a person's urine (pee), doctors call it hematuria (hee-ma-TUR-ee-uh). Hematuria is pretty common, and most of the time it's not serious.
Peeing is one way our bodies get rid of waste products. The process starts in the kidneys, which remove excess fluids and waste from the blood and turn them into urine. The urine then flows through tubes called ureters into the bladder, where it's stored until we pee it out. If blood cells leak into the urine at any part of the process, it causes hematuria.
There are two kinds of hematuria:
Microscopic hematuria is when blood in the urine can be seen only with a microscope. Often, this goes away without causing any problems. In fact, people might never know they have it unless they get a urine test.
Gross hematuria is when you can see the blood in the urine even without a microscope. This is because there is enough blood in the urine to turn it red or tea-colored.
What Causes Hematuria?
Blood leaks into the urinary tract. This can happen anywhere in the urinary tract such as:
in the kidneys, which remove waste and water from the blood to make pee
in the ureters, which are tubes that carry pee from the kidneys to the bladder
in the bladder, which stores pee
in the urethra, where pee leaves the body
Teens can get hematuria for many reasons. The more common causes are:
high levels of calcium and other minerals in the urine
a problem with the urinary tract
injury to the kidneys or urinary tract
taking some types of medicines, like some over-the-counter pain medicines
strenuous exercise (many athletes, especially distance runners, get hematuria from time to time)
Sometimes what looks like hematuria might be something else. Things like food dye, some foods (like beets or blackberries), the blood from your period and some prescription medicines can make pee look red.
How Is Hematuria Diagnosed?
If you ever see blood in your urine, don't panic. Chances are, it's no big deal. But you'll want to be sure, so tell your mom or dad and see a doctor. If you need treatment, it's good to get started right away.
The doctor will do an exam and ask about symptoms, recent activities, and your . You'll give a urine sample (pee in a cup) for testing.
If the urine test comes back negative, the doctor will probably want another urine sample 1-2 weeks later to make sure the urine is free of red blood cells. If hematuria only happens once, treatment usually isn't needed.
If urine samples point to something more serious or you've had a recent injury, you might need other tests, such as:
a urine culture (more peeing in a cup)
imaging tests like a kidney ultrasound, an MRI, or a CT scan
How Is Hematuria Treated?
Most teens who have hematuria won't need any kind of treatment for it. Hematuria that is due to a UTI will be treated with antibiotics.
If you've been treated for hematuria, your doctor will probably want you to get follow-up tests to make sure your urine is free of red blood cells.
When hematuria is a sign of something more serious — like kidney stones or a specific kidney disease — doctors will treat that condition.