Which of the following would indicate the presence of white blood cells in urine, i.e., pyuria?

Which of the following would indicate the presence of white blood cells in urine, i.e., pyuria?

• A. Bacteria
• B. White blood cells
• C. Red blood cells
• D. Crystals

Answer: (B)

Pyuria is defined by white blood cells in the urine. Their presence signals an immune response in the urinary tract, usually due to infection or inflammation, so they are the direct indicator of pyuria. In practice, this is detected by looking at urine under a microscope for leukocytes or by a leukocyte esterase test on a dipstick. The other findings don’t specifically indicate pyuria: bacteria may be present with or without WBCs, red blood cells point to bleeding in the urinary tract, and crystals are mineral formations. So, identifying white blood cells in urine best indicates pyuria.

Pyuria is defined by white blood cells in the urine. Their presence signals an immune response in the urinary tract, usually due to infection or inflammation, so they are the direct indicator of pyuria. In practice, this is detected by looking at urine under a microscope for leukocytes or by a leukocyte esterase test on a dipstick. The other findings don’t specifically indicate pyuria: bacteria may be present with or without WBCs, red blood cells point to bleeding in the urinary tract, and crystals are mineral formations. So, identifying white blood cells in urine best indicates pyuria.