What is hematuria?
Hematuria means that red blood cells are in the urine. Urine does not normally contain red blood cells. The filters in the kidney prevent blood from entering the urine. When you have hematuria, the filters in the kidneys or other parts of the urinary tract (the kidneys, ureter, and bladder that work together to remove wastes) allow blood to leak into the urine. There are two types of hematuria; microscopic or gross hematuria. Microscopic hematuria means that the blood can only be seen with a microscope. Gross hematuria means the urine appears red or the color of tea or cola to the naked eye.
What causes hematuria?
Hematuria is common and can have many different causes.
These causes include:
- Inflammation of the kidney, urethra, bladder, or prostate (in men)
- Abnormal structures in the urinary tract
- Inherited diseases, like polycystic kidney disease , sickle cell disease, or hemophilia
- Mineral imbalances in the urine
- In some cases, no cause of hematuria may be found (idiopathic hematuria)
Structural Causes of Hematuria
Kidneys that contain cysts (fluid-filled sacs) or are blocked may lead to any type of hematuria. An ultrasound of the kidney can determine if an abnormal structure is causing blood in the urine.
Inherited Causes of Hematuria
Several different diseases that run in families can cause hematuria. These include Polycystic Kidney Disease, Alport Syndrome, inherited nephritis, certain types of hemophilia and, Sickle Cell disease in the African-American population.
Mineral Imbalances in the Urine
High levels of calcium in the urine can cause hematuria. The hematuria may be painless or cause pain in the area of the kidney and/or a burning feeling during urination. Those with high levels of calcium in the urine are more likely to have a family member with a history of kidney stones. Individuals that have this condition have a higher risk for having a kidney stone, but less than 10-15 percent develops a stone. Most adults with microscopic hematuria do not need treatment unless they have a kidney stone
Glomerulonephritis is a common cause of blood in the urine. There are many types of glomerulonephritis. Some of these are mild and resolve on their own while others are more serious and need medication. Blood tests can identify some kinds of glomerulonephritis. In some cases, a kidney biopsy may be needed to find the exact form of the disease
"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 is not a family history of kidney failure and other medical tests are negative; usually, no treatment is needed.
What are the tests for hematuria?
Adults who have microscopic hematuria with normal blood pressure and kidney function should have their urine checked over several months. If blood in the urine continues:
- A kidney ultrasound may be performed.
- Urine should be checked for protein and may be checked for calcium and creatinine (a waste product found in your urine).
- Blood test to determine kidney function and other tests may be performed.
- If all tests are negative, and blood remains in the urine, yearly checkups should be done.
Adults who have microscopic hematuria with high blood pressure, abnormal blood tests, a family history of kidney disease or high levels of protein in the urine may need to have a kidney biopsy.
How is hematuria treated?
If your hematuria is caused by an infection, like a urinary tract infection (UTI), hematuria is treated with antibiotics. Your healthcare provider will test your urine after treating you with antibiotics to make sure that your infection has cleared. The goal of your healthcare provider is to find the cause of blood in your urine. If no serious condition is causing hematuria, no treatment is needed.
Also in the A to Z Guide
Understanding your Lab Values
Urinalysis: What You Need to Know