A high white blood cell count on routine urine microscopy should be considered: 1. Infections of the urinary system, such as acute urethritis, cystitis, and pyelonephritis, can result in an elevated white blood cell count. When an infection occurs, leukocytes will tend to engulf bacteria at the site of infection, producing an elevated leukocyte count. More than 5 leukocytes per high-powered view is considered to be the presence of a urinary tract infection. The patient needs to be further questioned whether the symptoms are caused by urinary frequency, urinary urgency, and painful urination, and further urine culture examination is needed to identify the causative organism and give symptomatic medication.2. Contamination caused by the retention of urine specimens can also result in elevated leukocytes on microscopy. Patients usually do not have any urinary tract irritation symptoms, and do not produce pain, fever, urinary frequency, urinary urgency, etc.