Brian is a previously healthy 56-year-old white man who presents with progressive neuropathy and declining mental status over several months. The patient initially developed numbness of his fingertips and the balls of his feet and began to lose motor control of his hands, which manifested as dropping objects or flinging them as he tried to pick them up. As symptoms progressed, he had visual tracking problems that were severe enough to interfere with driving a car, and he developed short-term memory loss and slowing of cognitive function. His current vital signs are 117/70, 72, 98.6, 12, Ht 5’9” Wt 193 lbs.