Weird skin discoloration

[clg06d]

My dog recently developed a skin discoloration- well, more of a fur discoloration. The underskin hasn't seemed to have changed. I have tried cleaning it off with peroxide and nothing seems to change it. His attitude hasn't changed and it doesn't seem to hurt him when I touch or press on it. It was not there one day and then the next it just showed up. I had him at the dog park for a few hours and he was laying in the dirt there- so maybe its just an allergy? I just feel like it should have went away or something by now. Has anyone ever seen anything like it? or experienced something similar?

Like I said, it kind of looks like that fur got stained or something- but its in a very distinctive shape and won't wash off or go away. I have a picture but am not sure how to get it on here...

[Aleda M Cheng, D.V.M., C.V.A]

Thank you for the photo's!

It looks like porphyrin staining from your dog licking himself in that area.  Another possibility is a malassezia yeast dermatitis.

Has your dog been licking himself in this area?  Some dogs' saliva and tears contain a pigment called porphyrin which stains light colored fur a reddish brown or a dark brown.  If your dog has not licked himself than the alternative is a common skin yeast called malassezia which is a dark brown color.  It is a normal skin inhabitant in low numbers, but can become an infection if in high numbers.  Malassezia is usually secondary to Atopy (allergic skin disease).

[clg06d]

[IMG]http://i40.tinypic.com/2yloge8.jpg[/IMG]

or if that doesn't work
http://tinypic.com/r/2yloge8/5