From the Guidelines
Non-hemolyzed blood in a urinalysis (UA) suggests true hematuria, meaning intact red blood cells are present in the urine, which can result from various conditions including urinary tract infections, kidney stones, trauma, tumors, glomerulonephritis, or other kidney diseases. This finding indicates bleeding somewhere in the urinary tract, from the kidneys to the urethra. When blood cells remain intact (non-hemolyzed), it means they haven't ruptured during collection or processing, confirming that the blood is actually present in the urine rather than being an artifact of specimen handling.
Key Points to Consider
- The presence of intact red blood cells can be confirmed microscopically by seeing red blood cell casts or dysmorphic red blood cells, which help differentiate between glomerular bleeding (from the kidneys) and non-glomerular sources 1.
- Further evaluation is typically warranted to determine the underlying cause, which may include additional laboratory tests, imaging studies, or referral to a urologist or nephrologist depending on the clinical context and severity.
- Clinicians should include gross hematuria in their routine review of systems and specifically ask all patients with microscopic hematuria about any history of gross hematuria 1.
- The American College of Physicians recommends that clinicians should confirm heme-positive results of dipstick testing with microscopic urinalysis that demonstrates 3 or more erythrocytes per high-powered field before initiating further evaluation in all asymptomatic adults 1.
Conditions Associated with Non-Hemolyzed Blood in Urine
- Urinary tract infections
- Kidney stones
- Trauma
- Tumors
- Glomerulonephritis
- Other kidney diseases It is essential to approach each case individually, considering the patient's medical history, symptoms, and the results of the urinalysis to determine the best course of action for evaluation and treatment, as suggested by the American College of Physicians 1.
From the Research
Non-Hemolyzed Blood in Urine Analysis
- Non-hemolyzed blood in urine analysis (UA) suggests the presence of blood in the urine that has not been broken down or lysed 2, 3.
- This can be an indicator of various conditions, including urinary tract infections (UTIs), kidney stones, or cancers of the upper urinary tract and bladder 4, 5.
- The presence of non-hemolyzed blood in UA may be associated with an increased risk of developing renal pelvis/ureter cancer or bladder cancer, particularly in individuals with a history of UTIs or kidney stones 2, 6.
- However, the relationship between non-hemolyzed blood in UA and the risk of urinary tract cancers is not fully understood and requires further research 3, 6.
- Some studies suggest that the presence of non-hemolyzed blood in UA may be related to chronic irritation and infection in the urinary tract, which can increase the risk of cancer development 2, 4.