Prion Diease

My father-in-law is the patient. About a month ago we notice that all of a sudden his memory was fading fast. They did MRI showed bit abnormal left side of the brain eating away, CAT scan, EEG all was ok. No signs of Stroke or mini strokes. Did spinal tap those results were no cancer and protein level at 12? The doctor except it to be hirer for Prion Disease, What are the percentages supposes to be at for Prion Disease??  How long are they with us with Prion Disease?

Over this past month he has progressively gotten worse.  Short term memory is gone 5 minutes later he doesn't remember anything.  He own and ran a trucking company for 40 years. We were watching TV show about trucks and he was confused and acted like he never saw one before and his son tried to talk to him about the company and he has no memory of it. He believes people are there when then is no one there.

If it was mini strokes wouldn't his memory come back??   Oh also his white blood count has been a little elevated.