Inflammatory Bowel Disease (IBD) is a chronic disease of the gut, or gastrointestinal tract. Most affected dogs have a history of recurrent or chronic vomiting and/or diarrhoea. They may lose weight but are otherwise normal. Most eat well or have an increased appetite, and appear normal.
Inflammatory cells invade the lining of the bowel causing thickening of the bowel. This interferes with digestion and absorption of nutrients and with normal movement of the bowel.
When the cells invade the stomach walls or upper small intestine vomiting develops. Infiltration of the small intestine causes watery diarrhoea and weight loss. Infiltration of the large intestine causes diarrhoea coated with mucus and fresh blood. The entire gastrointestinal tract is sometimes affected.
Something in the diet triggers the disease in some dogs. Bacterial proteins are involved in other cases. In most cases we cannot find any underlying cause.
Diagnosis
IBD is diagnosed by ruling out other diseases. Blood tests rule out liver or kidney disease, pancreatic insufficiency and diabetes. Faecal tests rule out parasites like whipworms or giardia.
X-rays or ultrasound rule out some tumours or cancers in the abdomen.
If these tests are all clear we trial special low allergy, low residue or high fibre diets, depending on the part of the bowel most involved. If bacterial overgrowth is present we trial various antibiotics until we see improvement.
If there is no improvement we biopsy the bowel and a pathologist identifies the type of cells involved, assesses the severity of the inflammation and checks for cancer cells.
Treatment
If any diet has improved the condition we continue it.
Medication controls (not cures) the problem. We trial drugs like metronidazole, prednisolone and azathioprine until we find what suppresses the signs best. Most dogs stay on the appropriate drugs and diet for life.