Hematuria means blood in the urine. The bleeding can be from the tubes (ureters) running from the kidneys to the bladder, the bladder itself or the tube (urethra) that lets urine out of the bladder. This whole system is called the urinary tract. Blood can also come from the kidneys themselves. The cause might be physical trauma to the kidneys, tubes or bladder, a kidney stone or an infection. Sometimes you can see blood in the urine, other times you can't and it is found by testing the urine.
Hematuria might be from kidney disease. If suspected, your doctor can get advice from, or send you to a pediatric nephrologist. A pediatric nephrologist is a medical kidney specialist for kids. A urologist operates on the urinary tract, so that's the kind of kidney specialist you see for any problem that needs surgery.
The kinds of kidney disease that cause hematuria usually affect the kidney filters (glomeruli). These filters clean your blood all the time. The filters know what things stay in your blood and what things need to go out in the urine. Blood getting into the urine might mean the filters are "sick". Some people have hematuria, but the filters are not sick and the kidneys will be OK. The specialist can help find out if the kidneys need medicine or not.
X-ray or ultrasound of the kidneys can show if they look normal. Blood tests let us know if they are working normally and if there are any signs that certain diseases known to affect the kidney are in the body. Finding more than blood (for example: protein) in the urine is also a sign the hematuria really does mean sick filters. High blood pressure can also be a sign of kidney disease.
Two blood tests show how well the kidneys are working. They are the blood creatinine and blood urea nitrogen (BUN). There are other tests that measure other parts of kidney function and the specialist knows how to use them. If all these things are OK, then no medicine is needed.
If the nephrologist feels it is necessary to look at the filters themselves, a tiny piece of kidney needs to be removed (biopsy) with a needle and looked at with a microscope. If the problem has a treatment (not all kidney disease is treatable), the nephrologists will recommend it. If it seems like the kidneys are being hurt by the disease, the nephrologist has the experience and knowledge to try medicines that may help. If you (your child) have a specific kidney disease, only time will tell how the kidneys will respond to treatment, your nephrologists will discuss all options with you.