Hi - Hollysmom emailed me and asked me to post.
First off, this doesn't look like fungal to *me* at all. I'm not a vet but I've had a lot of experience with 'mange' generally (altho that's a misleading term -- there are two types of mange that pups your age get -both VERY different with different causes & resolutions totally).
The vet didn't give ivermectin for ringworm -- PROMISE. Ringworm is a fungus and ivermectin would not, under any circumstances, treat that. However, the vet *did* suspect sarcoptic mange. The operative question for you is very specific. Did the itchies stop FOR EVEN A DAY after the ivermectin shots?
The skin scraping was for demodectic mange - something quite different (and I suspect there may be some demodex involved here - I'd have to talk with you more to determine it). But you won't find sarcoptic mange on a scrape -- you just won't 99.99999% of the time. They're too fast -- unless you happen to get lucky and find a female who has burrowed to lay eggs and even then they usually don't stick around on a slide.
Sarcoptic mange is a big huge topic. Each species of mammals have their own specific 'variety' of sarcops. In humans, it's called "scabies". But a sarcop will feast on the blood of any warm-blooded animal. But they will return to their host of choice *usually* to breed. But unfortunately more and more vets are finding sarcops that are actually wildlife sarcops who are quite a home in dog skin. They may or may not be laying eggs in the dog -- but they sure will bite the heck out of them.
So that's where the question is -- if the ivermectin helped for even a day or two, then it probably IS sarcops. But the first time the dog went back outside and went sniffing around that place where squirrels, possum, coon, or any other critter may ahve been -- any residue sarcops will jump right back on and you're right back to square one.
Both types of mange are VERY VERY immune-related. Demodex is a gene-related flawed immune system. (again it's complicated -- the article I can send you will help explain that). But essentially the dog is overly-sensitive to demodex mites and the immune system doesn't keep them under control as it should.
Sarcops just plain prey on weakened animals. Puppies, old dogs, sick animals or animals that just aren't as healthy as they should be.
Now honestly a pup can have BOTH. And by the looks of those pictures, I gotta suspect that. Either that or it is also possible there is a contact allergy working here -- can you tell me where you live? If you live in the south and have St. Augustine sod, night-blooming jasmine, wandeirng jew in ANY form (house plant, or the several varieties that are very common outside in the South) that could easily explain the itchy pink skin as well. But typically you will find contact allergies in the more hairless areas like the belly.
This isn't straightforward -- I wish I could just look at your pictures and say "oh, it's a-----------" but I can't. But if I talked to you a bit more I might be able to help you figure it out.
I'm just a lady who has done rescue for a zillion years who has tended to help dogs with skin problems. So I've seen TONS of them. And often the tough ones are the ones that are a combination of more than one thing.
You make reference that this dog had a difficult beginning - if you can tell me more it would help.
Is the dog spayed yet??
I'm going to say something totally opposite here .... if a dog has a sub par immune system (for example a dog you suspect is potentially a dog that may get demodex or a dog that is having any kind of immune problem) -- SPAY EARLY and neuter early.
Why? Because sexual maturation is the BIGGEST hardest thing on the immune system of puppyhood. That and teething. It puts the body in turmoil and it is a huge drain on the body's resources. It is almost always sexual maturation that will make demodex or any sort of mange worse because it so depletes the immune system. Often dogs with demodex or sarcops just will NOT recover until they are spayed because the sexual maturation will keep the immune system totally depressed and it just won't let up. The only thing worse is estrus itself - and by then the animal can be so severely immune compromised it's difficult to get it on target again.
Spaying and neutering stops that cold -- it halts the incessant pressure of sexual maturation and altho surgery itself IS a stressor, it allows the body to recoup and build up.
Hollysmom -- you will see for a couple of weeks yet some immune compromise because the body is recovering from surgery. But ultimately spaying her early will have no ill effects.
I will go one further and this isn't something often discussed in spay threads. A dog that is spayed EARLY ... like at 2 months ... these dogs rarely have any spay incontinence problems at all. That's a whole other subject, but essentially when a spay is done when they are pretty well fully sexually mature, can leave the bladder 'hanging' without much support. A dog that is spayed early at 2 months? Nope -- the sex organs just plain don't develop. So the bladder stays 'connected' properly and doesn't drop (which is often the cause of spay incontinence).
If your dog is a purebred and you are worried about size, etc. -- the dog spayed earlier may get a bit bigger than normal -- but there are a lot of factpors but from an immune standpoint the spay will only help.