What is commonly seen in urine when there is renal calculi?

In cases of renal calculi, microscopic hematuria is commonly observed in urinary analysis. The presence of red blood cells in the urine occurs due to the irritation and damage to the renal tissue or urinary tract as the stones move. This process can cause microtrauma, leading to bleeding which manifests as hematuria.

Understanding why this is the correct answer involves recognizing that renal calculi can disrupt the lining of the urinary tract, resulting in blood being present. While squamous epithelial cells may appear in urine as a normal finding from the shedding of cells lining the urinary tract, they are not specifically indicative of renal stones. Similarly, neutrophils, which indicate infection or inflammation, may or may not be present depending on whether there’s a secondary infection associated with the stones. Therefore, while these elements can sometimes be seen alongside renal stones, they aren't as characteristic as the microscopic hematuria specifically linked to the presence of renal calculi.