Well, here we are again, trying to make sense out of a puzzle. This patient, who complains bitterly of pain and tenderness, does not fit the usual erysipelas picture, no? I have never seen an erysipelas patient in significant pain. Never more than a 6/10, anyway. So, what gives? Why did I emphasize the pain? Because if you listen to the patient, they might keep you out of the newspapers.
This patient has necrotizing fasciitis, which is known on CNN and Nancy Grace and FoxNews as the Flesh Eating Bacteria Disease. The main clue that will rock your world is the pain that is out of proportion to the physical findings. If you palpate around the area, you will have to scrape these patients off the ceiling, because it hurts so badly. Here's what one (and only one of you got this one) of our playas (Deb from Ohio) had to say: "You had me at "severe" pain. Necrotizing fasciitis. Something I never want to see again. During my surgical rotation in PA school, I saw this bacteria eat across a woman's chest, giving her a strep mastectomy!"
So, the etiologic agent can be strep, or also staph, including MRSA. If you see a frank cellulitis, always be on the lookout for this. You don't want Nancy Grace tut-tut-tutting on the air about your oversight.