ABSTRACT
The most common cause of acute confusional state in elderly patients is a chest or urinary tract infection. These may present atypically, without overt symptoms or a temperature, so looking for a rise in CRP roughly corresponding with the onset of confusion can suggest that performing a septic screen (blood cultures, chest X-ray, urine dipstick and culture) would be of use in finding the cause. Uraemia, liver failure, hyponatraemia, and hyper-or hypocalcaemia can cause acute confusional state, but more rarely than an infection in older patients.
