Any advice on how to manage it? avoid recurrence?

Looks like this is what has landed mum back in hospital for a second week. First week was kidney infection that went septic and put her in ICU.

Just want to help her as much as possible. I know she has to make dietary changes - but i'm not sure how drastic. Fatty food is a given - but does she also need to cut out acidic food (tomato, onion, cucumber) - she is accepting of losing some of the meat that she likes - said she'd swap to salad - but then we wondered if the acidic stuff in the salads would be a bad thing