Q. I have a 2-year-old Weimarmer who was very healthy up until about a year ago. Now he weighs 48 pounds. He is very thin, his ribs show, and he has diarrhea most of the time. I have taken him to two different vets, who have done extensive testing on him: blood work, a GI series, and chest X-rays. Everything comes back normal. I feed him small amounts of food at least six times a day. Sometimes he vomits, but not all the time. He does not have a megoesophagus. If he gets too much fat in his dog food, he gets very sick. I cannot find anyone who can give me a reason for this. Could he possibly have colitis or diverticulitis?
A. Diarrhea, weight loss, and vomiting, if ongoing, are always a serious medical concern. There are many scenarios that can cause this, but the list can be narrowed down with blood tests and X-rays. It sounds like your dog has had all the basic testing already, so I would be thinking about several conditions that are harder to diagnose.
Exocrine pancreatic insufficiency occurs when a dog’s pancreas is no longer able to absorb nutrients because of inadequate production of digestive enzymes. It is most common in German Shepherd Dogs, but can occur in any breed. A blood test called TLI is the test of choice to diagnose this condition. The TLI level will be very low if your dog has this condition.
The treatment for EPI is supplementation with pancreatic enzymes, similar to what a person would take with this condition. In addition, there are dietary modifications which you may already be doing (a low-fat, low-fiber diet).
Another condition that can cause weight loss, vomiting, and diarrhea is inflammatory bowel disease or IBD. (Abbreviations are very common in medicine; after a while you get used to using them.) This occurs when the immune system is hyperactive and infiltrates the wall of the intestine. This infiltration can cause decreased absorption, as well as protein loss through th e intestinal wall.