Intestine Infection - HGE symptoms

Last week was my frenchie's 1yr b-day and on her b-day she began vomitting, diarrhea, lethargic, just terrible. I took her to the vet and he has been treating her as if it was HGE. After 4 days, she was still vomiting. The vet gave her a fluid/dye that shows up during x-rays. The x-rays showed the dye made it all the way through her system, but slower than normal. Today, day 7, she was still vomiting. The vet opened up her stomach to look for any blockage. Nothing. He did notice that her small intestine was darker in color and said possibly infected. He sent a sample out for analysis and I'm just waiting. So basically, it's been a week and still in the diagnostic process. I'm hoping someone in here can give me any information to what might be causing this and treatment if any. Thanks in advance for any input.

[Aleda M Cheng, D.V.M., C.V.A]

I am sorry for the delay in answering.  I have been at a veterinary conference and just returned.  By now you may already know what the biopsy showed.  However, it sounded as if your dog may have had a bowel intussusception.  Intussusception is a telescoping of the bowel inside itself as a result of a severe GI disease such as HGE, or Parvo disease or other serious GI disease.  The intussuscepted piece of bowel loses it's blood supply and can actually die, or become very damaged.  Intussusceptions usually have to be excised surgically because the dead piece of bowel cannot heal on it's own.