My wife's dementia was preceded by many years of ill-health involving viral infections. These often produced ME-like symptoms that were a problem for months at a time. I've discussed these before:
http://adventureswithdementia.blogspot.co.uk/search?q=viruses
It's always seemed to me possible, if not likely, that these infections have had something to do with the development of the dementia.
For as long as I've known her she has 'broken out' in rashes very frequently, usually when she is ill. They are the kind of rashes, mostly on her back or chest, that often come as quickly as they go.
I've mentioned previously that since she has had the dementia, the viral illnesses have disappeared (though until she started taking Acyclovir, an anti-viral medication, she was having regular herpes outbreaks). But the rashes I'm talking about have continued and often coincide with periods when her dementia symptoms worsen.
I'm going to try and discover whether other people with dementia have similar rashes. I'd be interested to hear whether anyone else with dementia has experienced similar rashes.