@dahannan It is the 2008 Domain Security Controller template that is associated with the issue. I removed this monitoring and CPU usage returned to normal, not that that is exactly a solution. I'm new to Solarwinds, so I'm not aware of any method to re-import templates.
@oithim_yew Yes, I added the 2008 Domain Security Controller template with polling frequency reduced dramatically. That's a good suggestion for a workaround, since we do have redundant domain controllers so they can get polled at different times. (However, the CPU stayed at 100% for 20 minutes after initiating with 'poll now'. This was well after the 300 second timeout set in the template, and frequency of polling was set to 24 hours. I have removed the template again.)
By way of update to my last comment, the hotfix in KB 2505348 was already installed on the server. FixIt Pro never did finish analyzing the performance diagnostic that I asked it to do.