I can't help but feel it might have been set on by a long standing UTI Then again, her sister also has it, so it could also just be genetic. These factors are

I can't help but feel it might have been set on by a long standing UTI Then again, her sister also has it, so it could also just be genetic. These factors aren't mutually exclusive, and are likely complementary. Many (or pretty much all) women experience UTI's at some time in their lives, but few of them are so severe as to trigger dementia. The difference between those whose UTI's lead to dementia vs not is likely genetic (or epigenetic, which is a whole other topic/controversy).