Urinary infections in the elderly are usually triggered by dehydration because they don't drink sufficient fluid. It seems that the dehydration and infection combined quickly bring on a state of confusion in the healthy elderly, and is sometimes not quite so obvious in a person who already suffers from dementia. In either case rapid treatment with antibiotics resolves the problem. Although in the case of persons with dementia, this original diagnosis remains but is brought back to the level it was before the infection. Your wife is obviously well trained in the care of elderly persons in residential care, and so is able to quickly realise what the problem is, and obtain the correct care for the person. It's a pity that in many care homes the staff are not so well trained, with the resulting poor care for the sufferer. My friend who is 105yrs old and is in residential care, recently had an episode of urinary infection, which resulted in him becoming very confused indeed. This was quickly spotted, and a course of antibiotics soon brought him back to his usual state of clarity of mind. Thank heavens there are people like your wife around to care for such people, when they need it most. Best wishes. Schutz.