I don't know anything about the illness, but ask about allergies. I doubt it, but it wouldn't hurt to ask. Dogs react in different way to allergies, just like people do.

I do have tips for the eating issue. Digi was the same way. Wouldn't eat much & she was super skinny. I tried different methods over several months trying to find something that agreed with her, & I finally found it.

She wants her food left out 24/7 & will gobble down fish kibble. THis is the food I feed her
http://kingrattus.net/gallery/v/Pets...y+Smancy+Food/

This is a Canadian Only brand I think, but there are similar brands out there.

If you want to test to see if she LOVES fish, buy some fish, (tuna, salmon, Haddock, ect), make sure its cooked with no spices (if canned, no oil), & offer it to her warm, room temp, or cold. Digi doesn't care about the temp, she just wants her smelly fish kibble or some canned fish.

But I still need to leave it out 24/7, or she'll go days without eating anything or very little.