Why is there two plus signs for protein in the urine test?

In a urine test, when two plus signs (++) are detected for urinary protein, it typically indicates that the protein level in the urine exceeds the normal range. Possible causes may include:

1. Physiological factors: For example, strenuous exercise, excessive intake of high-protein diets, long-term sleep deprivation, and mental stress may cause temporary elevation of urine protein. In such cases, urine protein levels usually return to normal after lifestyle adjustments.

2. Glomerular diseases: The glomerulus is a key structure in the kidney responsible for filtering blood. Inflammation or damage to the glomerulus, such as glomerulonephritis or diabetic nephropathy, may lead to significant leakage of protein into the urine.

3. Tubular diseases: Abnormal function of the renal tubules may also cause proteinuria, for example, tubulointerstitial diseases.

4. Medication effects: Certain medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs) and antibiotics, may affect the kidneys and lead to proteinuria.

5. Infections: Urinary tract infections, pyelonephritis, and other infectious diseases may sometimes cause transient proteinuria.

6. Pregnancy: During pregnancy, especially in the later stages, proteinuria may occur due to increased physical burden on the body.