purplish ears and painful itching

Question
My 11 year old daughter has a female guniea pig we have kept now for almost a year.  It periodically develops itching almost to the point of making it uncomfortably madd.  It even squeals in pain at timeswhen scratching. Most recently it is developing purplish or even blue/black rims around the outside of both ears.  I do not know why this is happening and am concerned that the flesh is actually dying.  Could this be true?  What can be done? Does it have some kind of mite on the outer ear?  And why all the painful itching?

Answer
Hello Margo!
Simply put, mange mites. I suspect an infestation or perhaps something like them. I will give you a link to a GREAT site and directly to the page about mites. I suggest bookmarking this page. I suggest that whether you to think it is mites or perhaps something else on the 'hair loss' page then you MUST see a vet ASAP. This could determine the life or death of the piggy.

http://www.guinealynx.info/hairloss.html