What does the presence of WBCs in a urine microscopic exam indicate?

The presence of white blood cells (WBCs) in a urine microscopic examination is primarily an indicator of inflammation or infection in the urinary tract. When WBCs are found in urine, this typically suggests that the body is mounting an immune response to a potential infection, such as a urinary tract infection (UTI).

In cases of a UTI, bacteria invade the urinary tract, leading to the recruitment of white blood cells to the site of infection to help fight off the pathogens. This results in a higher count of WBCs in the urine, which is a key marker for diagnosing UTIs.

Other conditions can also cause elevated WBCs in urine, but they are less specific. For instance, while kidney dysfunction could lead to the presence of WBCs due to inflammation or damage, it is not as direct an indicator as the presence of WBCs associated with a UTI. Similarly, dehydration does not typically lead to an increase in WBCs, but rather can concentrate other substances in the urine. Therefore, the presence of WBCs in urine is most definitively associated with a urinary tract infection, making this option the most appropriate.