Here is my origional thread about 
hair loss . 
When I shaved him it looked like he had a bug bite on his upper hindleg, but never noticed him scratching or biting ferociously. 
He wasn't bald b/c there was very thin hair, but it was super silky compared to the rest of his coat. After he was shaved the rest of him was silky like his legs and the hair is showing some growth so all is well with Ranger. 
Glad I could help, but really if you notice anything don't hesitate to get it investigated by a vet!!