Red, bumpy, bald spot on scalp since childhood

I've had this red bumpy bald spot for as long as I can remember. My parents said it was a birthmark, but looking at baby pics, I don't notice them. Could be because it was probably smaller back then.

I noticed recently that it's spreading. If you look at the picture, the darker less bumpy part has been there since I was a child...granted it did not look that way (it looked like the red bumps around it now)....but after many years of having this I guess that what it eventaully looks like. It feels pretty hard and not as soft so I know it can't be Kerion..plus I read that's not long term.

Red, bumpy, bald spot on scalp.
Can anyone tell what it is. ANything helps.

http://i45.tinypic.com/w6zgg3.jpg