How do you get a dog to eat?

My dog is suffering from Lyme's disease. She hasn't had a decent meal in a couple weeks. Her appetite is getting smaller and smaller. I'm really worried, does anyone know about anything that would help her be more likely to eat? The vet gave me special food for her kidney's (because of repetitive kidney failures), but she doesn't eat it. If it helps at all my dog is an American Eskimo/Golden Lab mix. I don't know if eating habits are very different between small, medium, and large dogs. Please help!