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Why can urinary tract infection make urine appear cloudy?

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The most common cause of urinary tract infection is invasion into the urethra of Escherichia coli, a type of bacterium that normally inhabits the bowel. — urinary tract infection The most common cause of urinary tract infection is invasion into the urethra of *Escherichia coli*, a type of bacterium that normally inhabits the bowel.

In the context of a urinary tract infection (UTI), urine may appear cloudy due to the presence of bacteria and an increased number of leukocytes (white blood cells) in the urine.123

During a UTI, the body’s immune response to the invasion of microorganisms often results in the shedding of these cells into the urinary tract. A urinalysis typically confirms the infection by detecting more than 10 white blood cells per high-power field, alongside the presence of bacteria. Additionally, the urine may contain higher levels of ammonia than normal during an infection.123