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How are bladder stones and tumors linked to a higher risk of cystitis?

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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.

Bladder stones and tumor growths increase the risk of cystitis primarily by acting as physical obstructions that disrupt the normal function of the urinary bladder.1

Under normal conditions, the bladder is highly resistant to infection due to its protective protein layer and the regular flushing action of urine. However, when stones or tumors are present, they can interfere with this process, leading to the following complications:1

Obstruction: These masses can obstruct the flow of urine, causing it to stagnate within the bladder. Stagnation creates an environment where bacteria can more easily colonize and multiply, significantly increasing the vulnerability of the bladder to urinary tract infections.231
Tissue Disruption: The presence of these foreign bodies can physically irritate or damage the bladder lining, compromising its integrity and making it more susceptible to inflammation and infection.1

In cases where an obstruction is present alongside inflammation, the bladder walls may become thickened and stretched, eventually leading to atrophy if the condition persists. Consequently, successful treatment of such infections often requires the removal of the underlying obstruction.12