Final answer:
An EEG in a 60-year-old with dementia and myoclonus is likely to demonstrate periodic sharp wave complexes and generalized background slowing, aligning with a diagnosis of Creutzfeldt-Jakob disease.
Step-by-step explanation:
In the case of a 60-year-old male presenting with new onset dementia and myoclonus, an electroencephalogram (EEG) would likely show findings consistent with Creutzfeldt-Jakob disease (CJD), a rare and fatal degenerative brain disorder. Key EEG characteristics of CJD include periodic sharp wave complexes along with generalized background slowing, which are seen in correlation with the rapid cognitive decline and the presence of 14-3-3 protein in the cerebrospinal fluid (CSF).
Although CJD is the most likely cause, it is critical that other potential causes of myoclonus and dementia, such as infectious or inflammatory processes, are ruled out; however, in this particular scenario presented, the CSF analysis showed no signs of inflammation or infection. The EEG may show characteristic findings associated with Creutzfeldt-Jakob Disease (CJD), a type of transmissible spongiform encephalopathy (TSE). The EEG may reveal a triphasic pattern, consisting of sharp waves occurring every 0.5-1.5 seconds, or a generalized slowing of brain activity.