Clinical Reasoning: A 47-year-old man with diffuse white matter disease and rapidly progressive dementia

A 47-year-old right-handed man without previous medical history presented to the University of Miami Memory Disorder Clinic for evaluation of progressive cognitive decline over a period of 4 months. He was initially noticed to have difficulty in finding his keys and documents and was not able to recall whether he had eaten lunch or dinner. The patient also had word-finding difficulties as well as remembering the meaning of a specific word. Upon further questioning, he also endorsed experiencing poor concentration and difficulty carrying out familiar tasks and for this reason he had to stop working. Additionally, there was also a reported weight loss of 20 pounds over the last 4 months. There was no known family history of dementia.