
My sisters 3 year old boxer bitch has been having similar problems. It started with hair loss on her side which spread to quite a large area, she had blood tests & biopsies, the vet said it was a form of alopecia. Then the front paws started to get itchy, (anal glands checked, not the cause), which got worse & worse despite daily washes in Malesab (I think). Next the bitch got itchy around her face and her scratching it caused scabs. The poor thing, she had pink itchy paws, scabby & bleedng face and a huge bald patch with big black blotches on it.
She had been on an exclusion diet to try to find the route of the problem, the vet suspects it's an alergy to something so has started with food. The dog is looking much better now, her itching has nearly gone and her big baldy patch is starting to slowly grow back, so hopefully they will get to the bottom of it.
In in all, I've probably been not much help here!! but I can sympatise with you as I know how much of a worry it has been for my sister.
ETA, my sisters boxer is white, so the black in the bald patch and the scabs on her face really show up, she looks like shes recovering from horrific injuries :(