I don't feeeeel
good.........
Frequently Asked
Questions
What is Inflammatory Bowel Disease?
Inflammatory bowel disease (IBD) refers to the
condition that results when cells involved in inflammation and
immune response are called into the lining of the GI
tract. This infiltration thickens the bowel lining and
interferes with absorption and motility (the ability of the bowel
to contract and move food). With abnormal ability to contract and
abnormal ability to absorb, the bowel’s function is
disrupted. Chronic vomiting results if the infiltration is in
the stomach or higher areas of the small intestine. A watery
diarrhea with weight loss results if the infiltration is in the
lower small intestine. A mucous diarrhea with fresh
blood(colitis) results if the infiltration
occurs in the large intestine. Of course, the entire tract from top
to bottom may be involved. Many people confuse inflammatory bowel
fisease with irritable bowel syndrome, a stress-related diarrhea
problem. Treatment for IBS is aimed at stress; it is a completely
different condition from IBD.
Why would the Veterinarian Think My Pet Might have
Inflammatory Bowel Disease?
A little vomiting or diarrhea here and there seems
to be pretty standard for pet dogs and cats. After all, cats groom
themselves and get hairballs. Dogs eat all sorts of ridiculous
things they aren’t supposed to. Still, many owners notice that
their pets seem to have vomiting or diarrhea a bit more often than
it seems they should. It might be subtle where one notices that one
is cleaning up a hairball or vomit pile rather more frequently than
with previous pets or it could be the realization that one hasn’t
seen the pet have a normal stool in weeks or months. Typically, the
animal doesn’t seem obviously sick. Maybe there has been weight
loss over time but nothing acute. There is simply a chronic problem
with vomiting, diarrhea or both. Inflammatory bowel disease is
probably the most common cause of chronic intestinal
clinical signs and would be the likely
condition to pursue first.
How is Inflammatory Bowel Disease
Diagnosed?
The first step in pursuing any chronic problem is a
metabolic database. This means a basic blood panel and urinalysis
to rule out more biochemically widespread problems (such as liver
disease or kidney disease) that could be responsible for the
signs. Since inflammatory bowel disease is localized to the GI
tract, such a database is usually normal (but might express a
general inflammatory response in the blood or a loss of blood
proteins as often there is a leaking of albumin (an important blood
protein) from the intestine into the bowel contents).
Radiographs may also be a good idea to rule out
growths in the abdomen or tumors that could be accounting for
the chronic problems. A trial of a
simple medication such as metaclopramide
(Reglan) or metronidazole (Flagyl) is often used to
see if there is symptomatic relief.
If this kind of non-invasive testing is not
revealing, then the definitive test for inflammatory bowel disease
is needed: a biopsy. Tissue samples must be harvested from several
areas of the GI tract. This can be done either surgically or via
endoscopy. Endoscopy involves the use
of a skinny tubular instrument (an endoscope) which has a tiny
fiber optic or video camera at the end. The endoscope is inserted
down the throat, into the stomach and into the small intestine and
small pinches of tissue are obtained via tiny biting forceps.
If the large intestine is to be viewed, a series of enemas is
needed prior to the procedure as well as a relatively long
fast. The endoscope is inserted rectally and again tissue
samples are harvested. The advantage of this procedure over surgery
is that it is not as invasive as surgery. Patients typically go
home the same day. Disadvantages are expense (often referral to a
specialist is necessary) and the fact that the rest of the abdomen
cannot be viewed. Growths that are seen via endoscopy cannot be
removed at that time and a second procedure typically must be
planned whereas, if surgical exploration is used to obtain the
biopsy, any growths can also be excised at that time.
Surgical exploration may also be used to obtain
samples. The recovery afterwards is typically a couple of days
though some patients bounce back immediately. With surgery, other
organs can also be sampled and abnormal sections of tissue can be
removed. Surgery tends to be more expensive than endoscopy but this
depends on the recovery period. Often these two procedures work out
to be of similar expense. Tissue
samples obtained are processed by a special laboratory and
analyzed. The infiltration of inflammatory cells is graded as mild,
moderate, or severe and the type of cells involved in the
inflammation are identified.
What Causes It?
Unfortunately, the causes of inflammatory bowel
disease are not well understood. Usually, a cause is not found. The
basic theory is that "something” is leading to a chronic stimulus
of inflammation. This could be an allergy against a food protein,
the continuing presence of a parasite, inflammatory products
produced by the normal bacteria living in the intestine or there
may be an underlying problem with the immune system in affected
individuals. Obviously, there may be different causes in different
individuals or a combination of the possibilities listed working
together. Most of the time an extensive search for the underlying
cause is not made.
What are Other causes of Chronic Vomiting or Diarrhea?
It is important to rule out parasitism as best
as possible in cases such as these. A fecal flotation for worms is
a good idea. Parasites such as whipworms or giardia may be
difficult to detect so a short course of treatment to rule out
their presence might also be a good idea, especially in the
dog.
Pancreatic enyzyme insufficiency or chronic
pancreatic inflammation might cause chronic vomiting or diarrhea. A
blood test called a trypsin-like immunoreactivity test is required
to rule out these possibilities. Pancreatic enzyme insufficiency is
an especially important problem in German Shepherd dogs.
More serious causes of chronic gastrointestinal
complaints might include intestinal cancer (especially
lymphosarcoma/lymphoma), fungal infection infiltrating the GI
lining, or a lymphatic condition called lymphangiectasia. A biopsy
will differentiate inflammatory bowel disease from these other
conditions.
An infection in the stomach with a bacterium
called Helicobacter is associated with
inflammatory bowel disease, but we do not know enough to establish
which is the cause and which is the effect. Helicobacter
infection can lead to ulceration and inflammation, compounding the
problems of the inflammatory bowel disease.
How is it Treated?
The cornerstone of treatment for inflammatory bowel
disease is suppression of the inflammation. In milder cases of
large intestinal inflammatory bowel disease, the immunomodulating
properties of metronidazole (Flagyl) might be adequate for control but usually prednisone is needed. Prednisone
will work on inflammatory bowel disease in any area of the
intestinal tract. In more severe cases, stronger immune suppression
is needed (as with cyclosporine or azathioprine).
Higher doses are usually used in treatment at first
and tapered down after control of symptoms has been gained. Some
animals are able to eventually discontinue treatment or only
require treatment during flare-ups. Others require some medication
at all times. Long-term use of prednisone should be accompanied by
appropriate periodic monitoring tests due to the immune suppressive
nature of this treatment.
Dietary manipulation may also be helpful in the
management of inflammatory bowel disease depending on the patient’s
interest in newer foods.
How Can Diet be Used to Treat IBD?
The first step in dietary management of inflammatory
bowel disease is fat restriction. Fat prolongs the time food spends
in the stomach, which tends to promote nausea. There can also be
undesirable interactions with fats and the bacteria of the
intestine.
The second step in using diet as therapy for this
condition is to use a protein source with which the patient is
inexperienced. Such a novel diet is considered hypoallergenic and
removes any immunological stimulation by dietary properties. While
there is no hypoallergenic diet that is appropriate for all
patients, many food companies have recognized the need for diets
such as these and something may be specially ordered. Such
diets are typically based on duck, venison, or rabbit
proteins. Some specialists
have recommended the use of what is called a sacrificial protein.
This kind of treatment involves using one novel protein during
initial treatment stages while the intestine is still inflamed and
switching to another one when signs have been controlled. The
theory is that an allergy to the initial protein is more likely to
develop while the intestine is still diseased.
Insoluble fibers have been helpful in
inflammatory bowel disease. They increase fecal bulk which
stimulates more normal motility from the intestine. Slower stool
passage results which enhances water absorption. Adding oat
bran to the hypoallergenic diet may be helpful.
Is it at all Reasonable to just Try Treatment and Skip
the Expensive Diagnostics?
Possibly. The problem with the prednisone trial
involves the possibility of intestinal lymphosarcoma (also called
lymphoma). This is a type of cancer that produces chronic diarrhea
or vomiting just as inflammatory bowel disease can. Lymphoma is
temporarily responsive to prednisone but the response is
short-lived. Exposure to prednisone will make the lymphoma much
more difficult to diagnose should biopsies be obtained later. Plus
exposure to prednisone can lead to resistance to other medications.
(This is less of a problem for cats, but in dogs even a few days of
prednisone can make a lasting remission impossible to
achieve.)
In short, if one tries prednisone without
confirming a diagnose, harm can be caused should a lymphoma be
present instead of inflammatory bowel disease.