Blood in urine, or hematuria, can indicate kidney infections, kidney stones, kidney injury or kidney disease, notes Mayo Clinic. Urine that contains blood may not have its normal pale yellow color, but may be pink, red or tea-colored, reports WebMD. In case of microscopic hematuria, the blood in the urine can only be detected by the lab, not with the naked eye.
Bacteria from the bloodstream may enter the kidneys, causing kidney infections or pyelonephritis, says Mayo Clinic. Symptoms of kidney infections include fever, confusion, nausea or vomiting and flank or back pain, states WebMD. Changes in urine due to this condition may include increased urgency of urination, pain when urinating, foul-smelling urine and blood in urine.
Crystals or stones may form from the minerals in the urine and develop inside the kidneys, causing a blockage that can result in significant pain and blood in urine, explains Healthline. A kidney disease such as glomerulonephritis can inflame the kidneys, causing urinary bleeding, notes Mayo Clinic. Triggers of this condition include blood vessel diseases, strep infections and diabetes.
Urinary bleeding may be a sign of kidney cancer, but symptoms may not be noticeable during early stages, reports Mayo Clinic. Kidney injury due to contact sports or an accident may also cause blood in urine. Patients should not ignore signs of blood in urine, as this condition can result in kidney failure if not treated, advises Healthline.