Hematuria (Blood in the Urine) in Children

• Gross hematuria is when blood can clearly be seen in the toilet or in a cup. This can happen with even a small amount of blood. Large amounts of blood or clots of blood in the urine are often an emergency, and you should get medical help right away.
• Microscopic hematuria is when the urine looks normal in the toilet or a cup, but blood is still present and can only be seen with a microscope. Many healthy children have microscopic hematuria that usually goes away on its own, though not always.

The most common causes of hematuria in children include:

• Heavy exercise
• Urinary tract infections
• High calcium levels in the urine (called hypercalciuria)
• Kidney stones
• Injuries that hurt the urinary tract or cause bleeding in other parts of the body, especially the muscles
• Structural problems or blockage in the urinary tract
• Genetic conditions that are passed down in the family, such as Alport syndrome, polycystic kidney disease (PKD), or sickle cell anemia
• Inflammatory kidney disease (Glomerulonephritis), such as IgA nephropathy (IgAN). IgAN is the most common type of inflammatory kidney disease that causes hematuria in children.
• Unknown cause (idiopathic hematuria): Idiopathic means that no specific cause can be found for blood in the urine. Idiopathic hematuria can run in families and is called familial idiopathic hematuria. When there’s not a family history of kidney failure and other tests are negative, then usually no treatment is needed.

While very rare in children, kidney cancer can also cause gross hematuria or microscopic hematuria.

Gross hematuria that involves heavy blood loss or blood clots could mean an emergency such as: 

• Large blood clots blocking urine flow out from the bladder
• Heavy bleeding that leads to low blood pressure and shock

If there is an underlying cause for the hematuria, complications can also occur if that is not treated or addressed.

Tests

One or more of these tests may be done for hematuria, depending on your child’s symptoms and the suspected cause.

Urine tests:

• Urinalysis (urine test): A test strip is placed in urine and changes color if there’s blood. This is just a screening test, so results must be confirmed by looking at the urine with a microscope.
• Urine culture: A urine test that looks for a urinary tract infection.
• Urine calcium: This test checks for high levels of calcium in the urine. High urine calcium can result in kidney stones or blood in the urine even if there are no stones.
• Urine protein: This test can help find out where the blood may be coming from. Having protein in the urine (also known as proteinuria) along with hematuria usually means there is a problem with the kidneys.

Blood tests:

• Serum creatinine: A blood test that checks how well your kidneys are filtering your blood.
• Complete blood count (CBC): A blood test that checks for anemia (not enough hemoglobin, often called red blood cells) and signs of infection (increased white blood cells).
• Complement proteins: This blood test helps diagnose some causes of a kidney disease called glomerulonephritis (inflammation of the kidney).

Other tests:

• Kidney and bladder ultrasound: An imaging test of the belly that uses painless sound waves to find cysts, kidney stones, tumors, and many other causes of hematuria.
• Kidney biopsy: This test is needed when the doctor thinks there may be damage to the filters of the kidneys. A needle is used to take a small sample of kidney tissue. Most children with blood in the urine do not need this test.
• Cystoscopy: This test looks for bleeding from the ureter, bladder, or urethra. It’s not common for children to need a cystoscopy. For this test, the doctor (a pediatric urologist) inserts a narrow tube with a tiny camera at the end of it to look at the bladder and urethra for the cause of the hematuria.

Treatment depends on what is causing the hematuria. Often, no treatment is needed. Infections are treated with antibiotics. If there’s a high level of calcium in the urine, eating less salt and drinking more water may help. Sometimes, medication may also help lower calcium levels in the urine.

For people with glomerulonephritis, treatment includes medications such as steroids or other medications that decrease inflammation (swelling) in the kidney. In some children, medication is also given to reduce pressure in the kidneys and help manage high blood pressure.  These medications are called ACE inhibitors or ARBs.

Kidney stones do not always need treatment but are sometimes removed if they are causing pain or infections. If your child is forming kidney stones, they may need further urine and/or blood testing to help prevent future stones.

In about 1 out of 4 cases, doctors may not be able to find the cause for the hematuria. If all tests are normal but blood still shows up in the urine, yearly checkups are needed to make sure your child does not begin to develop kidney disease.

Some medications, foods, and food colorings can cause symptoms that look like blood in the urine. Common examples include:

• Foods: Beets (beeturia), rhubarb, blackberries, senna (an herb)

• Red food dyes like red dye 40 

• Medications: ibuprofen (Advil, Motrin), iron pills, nitrofurantoin (Macrodantin, Macrobid), and phenazopyridine (Pyridium), rifampin, phenytoin, hydroxocobalamin (a synthetic form of vitamin B12)

• Do you check my child’s urine for blood at their yearly checkup?
• How often should my child’s urine be checked after blood is found in their urine?
• In between checkups, what signs and symptoms should I look for after blood has been found in my child’s urine?
• How many days should I wait after the end of my daughter’s period to get an accurate  test for hematuria?