The episode when she finally had it out with Denny's ghost he told her he was there because he was supposed to be helping her cross over, but he didn't want to tell her. Basially, he insinuated she was terminally ill and she told him to get lost. She is doing the tests to figure out what is wrong with her without telling people why she thinks she is sick (since she has no symptoms after all except the anemia she found in her bloodwork). If you missed the episode and want to catch up, they are all on abc.com and you can watch the entire thing with limited commercials for free.
at 2:07 PM on Feb. 11, 2009