What is the reason for the presence of red blood cells in urine tests

The appearance of red blood cells in urine tests may be caused by urinary tract infections, urinary system stones, nephritis, intense exercise, or menstrual pollution, and should be judged comprehensively in combination with other indicators.

1. Urinary tract infection: When bacteria invade the urethra, bladder, and other areas, causing inflammation, mucosal congestion and damage can lead to red blood cell infiltration into the urine. Commonly accompanied by symptoms of frequent urination and urgency, the white blood cell count in urine routine often increases synchronously. Mild infections can be treated with antibiotics, while severe cases require urine culture to determine the pathogen.

2. Urinary system stones:

Kidney or ureteral stones scratch the mucosa during movement, causing mechanical damage and bleeding. Usually accompanied by severe back pain or visible hematuria, B-ultrasound examination can clarify the location of the stone. Stones smaller than 6 millimeters are often treated with stone removal, while larger stones require extracorporeal shock wave lithotripsy.

3. Glomerular diseases: When the glomerular filtration membrane is damaged, such as nephritis and nephrotic syndrome, red blood cells will leak into the urine. The characteristic manifestation is positive urine protein and abnormal red blood cell morphology, which needs to be diagnosed through renal biopsy. Treatment should choose hormones or immunosuppressants based on the pathological type.

4. physiological factors:

Intense exercise may cause temporary kidney ischemia, allowing red blood cells to pass through the glomerular filtration membrane. Sampling during the menstrual period in women is prone to menstrual blood contamination. In such cases, the number of red blood cells is low and there are no other abnormal indicators. It is recommended to clean the midstream urine and have a follow-up examination.

5. Tumor or trauma:

Urinary system tumors, such as blood vessel rupture during the growth of bladder cancer, or kidney trauma leading to bleeding, will cause obvious hematuria. CT urinary tract imaging can clearly display space occupying lesions, which require pathological examination to clarify their nature and timely surgical intervention.

If abnormal red blood cells are found in urine, vigorous exercise and high salt diet should be avoided, and urine should be diluted with at least 2000 milliliters of water per day. Suggest rechecking mid morning urine and avoiding menstrual sampling for women. If it continues to be positive, further screening of the cause should be carried out through morphological examination of urine red blood cells, urinary ultrasound, etc. Long term hematuria may affect renal function, and regular monitoring of creatinine and urea nitrogen indicators is necessary. Pay attention to observing the color changes of urine in daily life. If there is a soy sauce color or washed meat like urine, seek medical attention immediately.