What is Inflammatory Bowel Disease (IBD)?
IBD results from an inappropriate response of the
immune system to substances presented to the gastrointestinal tract.
These substances might include proteins, carbohydrates, food
preservatives or bacteria in the stomach or intestinal tract. For some
unknown reason, the immune system begins to recognize one or more of
these substances as foreign and reacts by trying to rid them from the
body. The white blood cells of the immune system leave the blood stream
and migrate into the walls of the gastrointestinal tract. This causes
the walls to become thickened and decreases the ability of the stomach
and intestine to properly digest and absorb nutrients from the ingested
food. Any region of the gastrointestinal tract from the stomach through
the large intestine can be affected, and different regions may be
affected to varying degrees. For example, there may be mild inflammation
in the stomach, but severe inflammation in the small or large intestine.
Severe cases of IBD, particularly in cats, can progress to a cancer
called lymphosarcoma.
What are the clinical signs of IBD?
The clinical signs seen with IBD vary, but most commonly, the pet
suffers from one or more of the following clinical signs. These include
decreased appetite, nausea, vomiting, diarrhea or weight loss. The pet
may have any one of these clinical signs alone, or all of them depending
on the region of the gastrointestinal tract affected and the severity of
inflammation. The frequency of vomiting or diarrhea can vary from
multiple times daily to intermittent episodes. Some pets will begin to
lose weight, despite having a reasonable appetite. The clinical signs
may not be severe, and might be written off to the pet having a
“sensitive stomach”. Many pets have had intermittent episodes of
vomiting or diarrhea for months to years before seeking medical
attention.
Can I test my pet for IBD?
There are dozens of causes for vomiting, diarrhea, inappetence and
weight loss in cats and dogs. Before pursuing a diagnosis of IBD it is
important to rule out other causes of the clinical signs by performing
less invasive tests first. These screening tests might include fecal
examination, routine or more specialized blood tests and urinalysis to
screen for metabolic causes of the clinical signs, such as liver,
kidney, thyroid or pancreatic disease and viral testing in cats.
Radiographs and ultrasound may also be recommended to evaluate organ
size and texture and to look for evidence of masses. Ultrasound can also
look at the thickness and layering of the gastrointestinal tract. If
after these screening tests, it is still indicated, your veterinarian
may recommend endoscopy. This procedure requires the pet to be put under
general anesthesia. A long, flexible scope with a camera in the end is
inserted into the stomach and upper small intestine, where any gross
abnormalities can be visualized. If large bowel diarrhea is perceived to
be a problem, the colon and possibly the lower small intestine may also
be evaluated. Small pinch biopsies are taken from each region and
submitted to a pathologist. The pathologist is able to assess the
tissues on a cellular level and look for abnormal accumulations of white
blood cells in the stomach or intestinal walls. Endoscopic or surgical
biopsy of the affected tissues is the only reliable method of diagnosing
IBD.
How do you treat IBD?
Treatment is tailored to each individual pet and depends on the severity
of the inflammation and the clinical signs. Some pets will respond to a
hypoallergenic diet if the inflammation is triggered by a component of
the diet. Some pets require antibiotic therapy, as the compromised
stomach and intestine are more prone to overgrowth of certain types of
bacteria. Treatment of most pets is centered around suppressing the
abnormal immune response by using medications such as corticosteroids.
The goal is to use the lowest dosage of medication possible that
prevents the clinical signs of IBD from re-surfacing, yet minimizes the
side effects of the medications.
Can IBD be cured?
There is no cure for IBD, however approximately 80% of pets can be
controlled with diet change and medications that help to alleviate their
clinical signs. The remaining 20% may range from having recurrent
flare-ups of their clinical signs to not responding to medications at
all. Although the majority of patients will require some form of
life-long medication, the odds are in our favor that the pet’s IBD can
be controlled with the pet leading a normal, quality life.
