<unk> s may occur whenever the kidneys,<unk> , or ureters become inflamed, which may occur when the urine becomes too concentrated or when the body becomes dehydrated. Minerals such as calcium and magnesium crystallize into the<unk> s, which then can cause such symptoms as lower back or abdominal pain or difficulty with urination. The use of urinary catheters may cause a<unk> . Individuals who are paralyzed or are unable to adequately pass urine may require the use of small plastic tubes (catheters) placed into the<unk> . The use of these tubes may lead to an infection, which irritates the<unk> , resulting in<unk>  formation. Finally, a kidney<unk>  may travel down the ureter into the<unk>  and become a<unk> . There is some evidence indicating that chronic irritation of the<unk>  by retained<unk> s may increase the chance of<unk>  cancer. Urinary schistosomiasis, a disease caused by the digenean trematode Schistosoma haematobium, has been implicated in the development of vesical calculi. However, evidence accumulated thus far has not supported this hypothesis.
Bladder stone
Pyonephrosis
Hydronephrosis
Pyelonephritis
Ureteric stricture
Glomerulonephrosis
Interstitial cystitis
Hemorrhagic cystitis