Page 749 - Problem-Based Feline Medicine

33 – THE CAT WITH SIGNS OF CHRONIC SMALL BOWEL DIARRHEA 741

Alternatively, a commercially available hypoaller-
Classical signs—Cont’d
genic diet made from a single novel protein or protein
hydrolysate is also a useful test diet. Once a diagnosis ● Weight loss, anorexia and dehydration may
of food sensitivity (food intolerance or food allergy) occur if severely affected.
has been made, a commercial hypoallergenic diet con- ● Most adult cats will be asymptomatic or
taining novel protein and carbohydrate sources should have subclinical infections.
be used for long-term maintenance, as homemade diets
are rarely balanced and complete. See main reference on page 705 for details (The Cat
With Signs of Acute Small Bowel Diarrhea).
Intestinal biopsies from cats with food intolerance
may be normal, or may have mild to moderate infil-
trates of lymphocytes, plasma cells or eosinophils, Clinical signs
depending on the duration of intolerance and severity
The principal clinical sign of coccidiosis is acute
of clinical signs.
small bowel diarrhea, which may be bloody, mucoid
or watery. It usually occurs in young cats or kittens
Differential diagnosis as acute diarrhea, but may persist and present as
chronic diarrhea. In severely affected kittens, weight
Intermittent but unrelenting vomiting in an other-
loss, anorexia and dehydration may also occur.
wise healthy cat suggests gastrointestinal motility dis-
turbance, gastric parasites, early inflammatory bowel Other signs that may be observed include vomiting,
disease or antral pyloric hypertrophy. weight loss, lethargy and dehydration.

In cats where diarrhea is the presenting sign or Adult cats that are infected with coccidian parasites
occurs in addition to vomiting, hyperthyroidism, (including cryptosporidia) are typically asymptomatic.
chronic pancreatitis, early renal or liver disease, and
Young or immunocompromised cats with cryp-
other primary GI abnormalities such as neoplasia or
tosporidiosis will have profuse, watery diarrhea and
intermittent intussusception, must be considered.
mesenteric lymphadenopathy due to intestinal hyper-
secretion and malabsorption.
Treatment
Toxoplasma infections are also rarely associated with
Change to a diet that does not contain the offending diarrhea, but in cats with immunocompromise or other
substance. This may be as simple as changing from significant bowel conditions (e.g. IBD), quiescent toxo-
a grocery store brand to a premium brand food (or vice plasmosis may be re-activated and cause clinical signs.
versa), but also may require changing to a hypoaller-
genic food diet (e.g. IVD’s Limited Antigen diets, Hill’s
d/d or z/d, Eukanuba Response formula, Royal Canin Diagnosis
Select Protein) or in some cases, formulating a home-
Diagnosis is made by identification of isosporoid
made diet that is complete and nutritionally balanced.
oocysts in fresh feces.
Since the abnormal gastrointestinal response is non-
The oocysts of cryptosporidia are 1/10th the size of
immunologic, use of oral prednisolone is not likely to
Isospora (smaller than RBCs and 1/16th the size of
be beneficial.
a Toxocara cyst). Toxoplasma oocysts are only
slightly larger.
COCCIDIOSIS (ISOSPOROSIS,
CRYPTOSPORIDIOSIS, TOXOPLASMOSIS)** Special flotation media (Sheather’s sugar or zinc sul-
fate flotation) is required along with special staining
Classical signs (Kinyoun’s carbolfuchsin negative) or phase contrast
microscopy, to identify cryptosporidia.
● In young cats or kittens acute small bowel
diarrhea occurs. Other methods of identification of fecal cryp-
tosporidia include an ELISA test, but its effectiveness