Irritable bowel syndrome (IBS)
is an intestinal disease of humans that involves diarrhea and abdominal cramping
of unknown cause. It is not a well-defined disease process in veterinary
medicine, but is believed to be associated with some sort of functional disorder
of intestinal motility or movement, rather than an infectious, inflammatory,
or cancerous problem.
It is a chronic (long term) problem with intermittent clinical signs and
is primarily a disorder of dogs. There are no breed or sex predilections.
Some authors suggest that stress plays a role in the disease process, because
IBS has been noted in high strung dogs and performance and working dogs.
What to Watch For
Intermittent bouts of diarrhea or soft stool
Increased frequency of defecation
Passage of small volumes of stool
Straining to defecate
Abdominal distension/bloating
Excessive gas
Abdominal discomfort
Occasional nausea and vomiting
Diagnosis
History and physical exam
Complete blood count (CBC)
Biochemical profile
Urinalysis
Fecal tests for parasites, protozoa and bacteria
Fecal cytology
Tests for bacterial overgrowth in the intestine
Food trial
Abdominal ultrasound
Endoscopy and intestinal biopsy
Treatment
Dietary modification
Anti-diarrheal drugs
Anti spasmodic/tranquilizer combinations for abdominal bloating and pain
Drugs to minimize gastrointestinal gas
Home Care and Prevention
Give all medications as prescribed by your veterinarian. Careful adherence
to dietary recommendations is crucial. Feed only the prescribed diet. Do
not feed table scraps or other foods, including natural chew toys (rawhides).
Observe for inappropriate response to treatment or worsening of clinical
signs at home. Persistent diarrhea, lack of appetite, abdominal discomfort,
and lethargy should prompt a call to your veterinarian.
Because of the possible role that stress may play in this disease process,
potential stressors in the home environment should be identified and minimized
when possible.
Information In-depth
IBS is thought to be caused by abnormal motility or movement of the intestinal
tract. It generally causes chronic and intermittent signs, but the affected
animals do not lose weight and otherwise appear healthy. Certain patterns
of illness may appear following a stressful event in the animal's life. The
most common signs are bouts of diarrhea and abdominal cramping, bloating
or discomfort. There is no specific test to diagnose IBS, so it is therefore
a diagnosis of exclusion. This means that all other known causes of gastrointestinal
disease that produce similar clinical signs must be ruled out prior to making
an appropriate diagnosis of this disease process. Other diseases that may
cause similar clinical signs include:
Diseases involving other body systems that have gastrointestinal side effects.
These might include diseases affecting the kidneys and/or urinary tract,
liver, immune system and endocrine system (hormone producing glands).
Bacterial infection of the GI tract.
Campylobacter, Salmonella and Clostridium are types of bacteria that can
infect the GI tract and cause diarrhea and vomiting.
Parasitism.
Intestinal worms or Giardia (a protozoal organism) can also cause vomiting
and diarrhea.
Food allergy or intolerance.
Animals that have allergies or an intolerance to certain foods may manifest
their allergies via diarrhea and/or vomiting.
Overgrowth of GI bacteria.
The GI tract normally contains many normal bacteria; however, excessive growth
of the bacteria may lead to an overabundance, which impedes normal GI function.
Inflammatory bowel disease (IBD).
IBD is a common cause of diarrhea and vomiting in both dogs and cats.
The clinical signs may be very similar to IBS, but it is a different disease.
IBD is characterized by the presence of inflammatory cells in the lining
of the intestinal wall, as noted by intestinal biopsy.
Fungal disease of the GI tract. Histoplasmosis and Pythiosis are fungal infections that can involve the
GI tract and cause vomiting and diarrhea. These infections are specific to
certain geographical areas.
Neoplasia.
Cancers affecting the GI tract, most notably lymphosarcoma, can cause similar
clinical signs as IBS. Lymhposarcoma is a cancer of the lymphoid tissues,
of which there is an abundant supply in the GI tract.
Veterinary Care In-depth
Diagnosis In-depth
A history and physical exam are necessary to guide the diagnostic work-up.
Careful history taking should help determine if the clinical signs are consistent
with the classical presentation of animals with IBS. Physical exam findings
of animals with IBS are usually unremarkable. Abnormalities found on the
physical exam may be more suggestive of another disease entity.
Complete blood count.
The CBC evaluates the red and white blood cells as well as the platelets.
The CBC is usually normal in these patients, but it may be helpful to rule
out other disease processes that may cause signs similar to IBS.
Biochemical profile.
The biochemical profile helps to evaluate liver and kidney function as well
as assessing blood sugar, protein and electrolyte levels (sodium and potassium
are examples of electrolytes). This is imperative in ruling out diseases
of other body systems such as liver and kidney disease.
Urinalysis. Evaluation of the urine together with the biochemical profile is necessary
to fully assess kidney function.
Fecal tests. Fecal analysis is necessary to diagnose bacterial and
parasitic infections. A fecal float looks for worm eggs. A fecal culture
is necessary to rule out the bacterial causes of infection, and there is
a specific fecal test to diagnose Giardia.
Fecal cytology.
This involves examining the feces under a microscope to look for evidence
of inflammatory cells, which may be indicative of an infectious process or
another disease such as IBD. Fecal cytology should be normal in patients
with IBS.
Bacterial overgrowth can be assessed in several ways. One method involves
getting samples of intestinal juice and culturing it to evaluate the total
number of bacteria present. Bacterial overgrowth can also be implied by measuring
blood levels of cobalamin (Vitamin B12) and folate. Cobalamin is often consumed
by bacteria and folate is a substance produced by bacteria. Therefore, alterations
in the levels of these two substances can be suggestive of bacterial overgrowth.
Food trial.
Switching the animal's food to a new diet or a hypoallergenic diet may indicate
an allergy to a specific food if the signs resolve following cessation of
the previous diet.
Abdominal ultrasound.
Ultrasound exam of the abdomen may help pinpoint the site of the problem.
Animals with IBS have normal exams. Evidence of intestinal thickening or
enlarged lymph nodes or tumors in the abdomen will help exclude a diagnosis
of IBS.
Intestinal biopsy. Biopsy of the intestine is necessary to rule out
inflammatory and cancerous causes of the clinical signs. This is often done
via endoscopy, which is a scope placed into the animal's intestinal tract
either via the mouth or the rectum. Biopsies of the stomach as well as the
small and large intestine can be obtained by this method.
Therapy In-depth
Treatment principles for IBS involve manipulating the diet to create a highly
digestible food source. Additionally, many animals respond favorably to addition
of fiber to the diet. Fiber is thought to normalize gastrointestinal motility.
Many animals will not respond to dietary therapy alone and may require anti-diarrheal,
anti-spasmodic, anti-gas and even tranquilizing drugs during episodes of
marked discomfort.
Dietary modification.
A diet that is low in fat and highly digestible is recommended. This should
be a diet that the pet has never eaten before. Hypoallergenic diets may also
be used. Fiber can either be added to the diet, or high fiber formulations
may be prescribed. It is important to note that each animal is different
with respect to their response to a particular diet and the dietary modification
must be tailored to the individual.
Antidiarrheal drugs.
Loperamide (Imodium) and diphenoxylate (Lomotil) are drugs that may be useful
in dogs whose predominant signs are diarrhea and urgency to defecate. They
work by decreasing intestinal secretions, promoting absorption, and altering
intestinal motility. They should be used under the supervision of your veterinarian,
as some dogs may have worsening of bloating and abdominal discomfort as a
side effect.
Antispasmodic/tranquilizer medications.
Librax is one example of a combination drug that may alleviate discomfort
associated with bloating. It contains a Valium-type sedative and an antispasmodic
agent that reduces intestinal motility. This type of drug is generally used
on a short-term basis only.
Anti-gas drugs.
Over the counter medications such as Gas-X and Mylanta-Gas contain a drug
called simethicone, which alleviates intestinal gas. This is another drug
that should only be used after consulting with your veterinarian.
Follow-up
Optimal treatment for your pet involves a combination of home and professional
veterinary care. Follow-up can be critical, especially if your pet does not
rapidly improve.
Administer all prescribed medications as directed. Alert your veterinarian
if you are having problems treating your pet.
Strict adherence to a new diet is imperative to successful dietary therapy.
The prescribed diet should be the only food that your pet eats. This means
that all treats (unless made of the same formulation as the new diet), table
scraps and natural chew toys or flavored toys must be eliminated. It is important
to notify your veterinarian if your pet is not adjusting to the new diet
and is not eating appropriate quantities. Problems with palatability may
require changing the diet or even formulating a special home-cooked diet
in certain cases.
IBS can be a frustrating disorder because of its chronic and intermittent
nature.Flare-ups should be expected. It is important to try to determine
if recurrence of signs coincides with any specific activities or changes
in your pet's environment. All possible stressors should be minimized as
much as possible.
IBS is not a life threatening disorder and will not shorten your pet's life
expectancy. Careful observations and coordinated care with your veterinarian
will allow you to determine the proper therapy for your pet and hopefully
minimize flare-ups.
Once a full work-up has been completed, the need for follow-up care will
depend on how your pet is doing at home. If signs are becoming more frequent
or worsening, repeat diagnostics may be necessary.
This article has been provided courtesy of PetPlace.com
(www.petplace.com), the definitive
online source for pet news, health,
and wellness information.
The above information is simply informational. It's intent
is not to replace the advice of a veterinarian nor to assist you in making
a diagnosis of your pet. Please consult with your own veterinarian for confirmation
of any diagnosis. Your pets life may depend on it.
