Blood is normally not present in the urine, apart from menstrual blood, which may contaminate urine samples.
Hematuria is associated with renal or genital disorders in which the bleeding results from irritation to the involved organs or some type of trauma. Examples include:
- Renal calculi
- Pyelonephritis
- Glomerulonephritis
- Tumors
- Trauma
- Exposure to toxic chemicals or drugs
- Strenuous exercise
Hemoglobinuria may be due to the lysis of red blood cells within the urinary tract. This can be caused by intravascular hemolysis as the hemoglobin is filtered through the glomeruli. In a healthy individual, the hemoglobin molecule attaches to haptoglobin and bypasses the kidney filtration system. When the hemoglobin/haptoglobin system is overwhelmed, hemoglobin passes into the urine. Hemoglobinuria may be associated with:
- Hemolytic anemia
- Severe burns
- Transfusion reaction
- Infection
- Strenuous exercise
