We attempt to classify each case of diarrhea as either a major problem or a minor problem and localize the source of the diarrhea to the small intestine or large intestine (or both). It is important to determine how long the diarrhea has been present and whether the cat has lost weight. We use all of the information gathered to formulate a plan for diagnostic and therapeutic procedures.

Contributing Factors

Some potential risk factors for diarrhea include dietary indiscretion, exposure to certain illnesses, contraction of feline leukemia or immunodeficiency viruses, and travel to areas of endemic fungal infection.

Clinical Signs

With minor causes of diarrhea, the cat may have no signs of illness other than the loose stool. Major causes of diarrhea result in the cat being visibly ill and exhibiting several, but usually not all, of the following signs: vomiting, dehydration, loss of appetite, abdominal pain, high fever, lethargy, or bloody and/or watery diarrhea

Causes

Minor causes of diarrhea include stomach or intestinal viruses, intestinal parasites, and dietary indiscretions (such as eating garbage or other offensive or irritating materials). Major causes of diarrhea may include inflammatory bowel disease, neoplasia, fungal or bacterial infection, hyperthyroidism, and loss of pancreatic function.

Diagnosis

If your cat does not exhibit the clinical signs of a major case of diarrhea, we classify it as a minor case. A minimum number of tests are performed to rule out common causes. These may include a physical examination, fecal exam for parasites, and possibly an x-ray.

For cats that are visibly ill with diarrhea (major case), diagnostic procedures are usually implemented quickly. We perform a series of tests that allow us to make a diagnosis so that specific treatment may be initiated. These tests may include tests for feline leukemia virus and feline immunodeficiency virus, radiographs (x-rays) with or without barium, blood tests, stool cultures, biopsies of the intestinal tract, thyroid profiles, and exploratory abdominal surgery. Once a specific diagnosis is made, treatment may include special medications and/or diets, or surgery.

Therapy

With minor cases of diarrhea, treatment may be geared toward one or more of the common causes of uncomplicated diarrhea. Even with negative fecal examinations, many cats with uncomplicated diarrhea are routinely dewormed. Other therapies often include drugs to control the motility or relieve inflammation of the intestinal tract and, often, a special diet for a few days. These approaches allow the body's own healing mechanisms to correct the problem.

With major cases of diarrhea, initial therapy may be supportive. This would include fluid replacement, electrolyte replacement, and perhaps antibiotics. Additional therapy will depend upon the diagnosis.

Prognosis

With minor (uncomplicated) cases of diarrhea, we expect improvement within 2-4 days of initiating therapy. If this does not occur, a change in medication or additional testing may be needed to further define possible causes. Please keep us informed of lack of expected improvement so that we may manage the situation properly.

Transmission to Humans

Some of the bacterial and parasitic causes of diarrhea are infectious to humans. If any members of your household are also experiencing diarrhea, it is important to let us know. This will allow the veterinarian and physician to work together in managing potentially infectious causes.

Prevention

Preventive measures are directed toward the specific diagnosis.