My dog has recently developed spots of hair loss, what could this be?

My 2 year old female German Shepherd has recently developed spots on her back between her hips of hair loss. It appears as though the undercoat is there and there is a light top coat that remains. We have taken her to the vet and have ruled out food allergies. The spots are not bilateral but rather sporadic spots that vary in shape and size. She bites and grooms as usual and we have her on flea and tick treatments. There has also been mild hair loss on the back of her legs near her rump. It does not cause her discomfort and the spots are not red or irritated. Before taking her to a dermatologist I was hope to get some feedback. Does anyone know what this could be? Any in home treatments? Ever had an experience like this before?My dog has recently developed spots of hair loss, what could this be?
most likely mange. flea medication doesnt always protect against mange- my dog got it when he was littler. you need to get a skin scrape (its hardly painful at all- i know it sounds like death D:)My dog has recently developed spots of hair loss, what could this be?
has your vet done a skin scraping to check for demodetic or sarcoptic mange? if you have ruled out food alllergies and fles, this is another possibility.