The very edge of Spirit's ear is dried...

This is a hard symptom to explain - I tried to take a picture but it didn't show what I'm seeing. The edge of Spirit's ear looks as though it's dry, kind of. There's a little bit of a crusty brown substance right on the edge, and I pulled a little off, and the hair came off with it so easily. I thought, maybe ringworm, but it's just some dried brown "grains" stuck on the edge of his ear, and no circular hair loss.

I adopted Spirit 2 weeks ago - he's about 6 months old, and came to me with worms, a respiratory virus, and ear mites, all of which were treated by my vet but I don't know that he's kicked any of them yet.

Do you think this is a symptom of ear mites? The ear that this is on is also the ear that seemed to be most heavily infested. He's had brown gunk coming out of that ear since a week after the vet put the drops in.

I also wonder if he has a food sensitivity because he still has diarhea or soft stool, and he's been grooming (licking) himself a lot. I have just started switching him from Science Diet to Blue Spa kitten formula. Blue Spa is a natural food, no corn or soy and no by products of course.

Any opinions would be welcome.

Has he been out in the cold? That could be frost bite.

Interesting thought, but if he was ever out in the cold it was at least 2 months ago, because he was in foster homes and shelters since then, until I adopted him.

I just called and made an appointment at the vet for that and to check up on his respiratory virus because he's still sneezy. The soonest I can bring him in is Wednesday, so I'll see how it develops over the next couple days.