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How do abnormalities of the renal system raise the risk of urinary tract infection?

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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.

Abnormalities of the renal system increase the risk of urinary tract infection primarily by disrupting the normal flow of urine. When the urinary tract is obstructed—whether by congenital anomalies, such as malformed kidneys or ureteral blockages, or by other structural issues—urine can stagnate. This stasis creates an environment that facilitates the growth and ascent of bacteria into the renal pelvis and kidney tissue, leading to intractable infections that are difficult to eradicate until the obstruction is relieved.1234

Additionally, certain functional abnormalities, such as an incompetent ureterovesical valve, can cause vesicoureteric reflux, where urine flows backward into the ureter and pelvis. This process not only directly damages the kidneys but also promotes the development of infection. Because these structural and functional impairments prevent the effective flushing of the urinary tract, they significantly heighten susceptibility to both acute and recurrent infections, which can eventually lead to chronic renal damage or failure.1234