“Can urine infection cause kidney failure?”

Recurrent UTI can cause kidney failure.

Typically, a urinary tract infection means a bladder infection and does not cause kidney failure. But if a urinary tract infection flares up and gets into the blood stream, then it can make a patient very sick. Infection can cause low BP, and low BP in itself can cause kidney tubular damage and kidney failure. Sometimes, UTI signifies a kidney infection rather than a bladder infection and can be more serious than just a bladder infection.
Your healthcare provider can differentiate a bladder infection from a kidney infection and can treat you optimally so that it does not flare up and result in complications.
I hope the above answered your questions,if you need additional clarification, then do elaborate on additional concerns or questions.

If not treated

Not usually. It is very rare for a urinary infection to cause kidney failure by itself.

A simple, single urinary tract infection will not result in kidney failure. But a severe urinary tract infection can result in sepsis and some times acute kidney injury and renal failure (any kind of infection, if it is severe, can result in acute kidney injury and renal failure). Especially elderly people are more susceptible to getting sepsis with UTI. It is better to prevent recurrent infection, if you know the precipitating factor.
Hope this will help you. Pls contact with any further questions/concerns.
Thanks.