Urinary tract infections are most commonly seen clinically when a white cloudy fluid is produced with pain. A urinary tract infection, also known as a urinary tract infection, is an inflammatory response caused by bacterial invasion of the urinary tract epithelium. The most common is the infection of the lower urinary tract, and the causative agent of lower urinary tract infection is usually Escherichia coli. The clinical manifestations are mainly bladder irritation signs, i.e. frequent, urgent and painful urination, discomfort in the bladder area or perineum, burning sensation during urination, and cloudy urine. A routine urine examination will reveal an increased white blood cell count, with pus cells, often greater than 5 per high-powered view. At the end of urination, sometimes there will be terminal hematuria or even blood clots discharged. Therefore, white cloudy urine with pain is usually caused by urinary tract infections and can be diagnosed by a routine urine test.