Suggest Treatment For Fever With UTI

My mom is 65 and has had fevers every month for 10 days for last 3 months. She was diagnoised with creatinine levels of 1.9 and is arthritic and had her 2nd replaced in January. Her recent fever was diaognized us UTI. Any thoughts on what are her options for treatment and is now bed ridden with lumbar pain and non responsive new knee even though she was walking for 4 months after surgery