Hematuria

Hematuria, also spelled haematuria, is the presence of blood or red blood cells in the urine. Gross hematuria occurs when urine appears red, brown, or tea colored due to the presence of blood, while hematuria may also be subtle and detectable only with a microscope or laboratory test. Blood that enters and mixes with the urine can come from any location within the urinary system, including the kidney, ureter, urinary bladder, urethra, and in men, the prostate. Common causes include urinary tract infection, kidney stones, viral illness, trauma, bladder cancer, and exercise, grouped into glomerular and non-glomerular causes depending on the involvement of the glomerulus of the kidney. Not all red urine is hematuria, since certain medications, some foods, and menstruation can also cause urine to appear red or give a false positive test result.