How To Avoid UTIs While Having Spina Bifida With Neurogenic Bladder?

i know someone who is suffering from spina bifida associated with neurogenic bladder by birth. he gets recurrent UTIs and takes strong antibiotics everytime he gets it. he is on intermittent self catheterization and also has to manually excavate stools. i need to know the long term effects of recurrent UTI on his health (on kidney s and other body parts too)and also the long term effect on being on antibiotic therapy (he takes atleast 1-2 course of antibiotics per month). how can he avoid getting UTIs and live a better life. also what are the precautions he needs to take for the rest of his life so that his condition does not deteriorates any further. the ultrasound shows he has hydronephrosis and his left kindney has shrunk to 7.5 cm in size. the place he is staying right now is not very hygenic so what all are the precautions he needs to take.thanks so much.will be eagerly wating for help and more information.