Page 317 - Problem-Based Feline Medicine

17 – THE CAT WITH WEIGHT LOSS AND A GOOD APPETITE 309

● When performing laparotomy or laparoscopy it is Treatment
advisable to collect biopsies of the mesenteric
The basic aims of treatment are to remove the source of
lymph nodes, liver and, if possible, pancreas, as
antigenic stimulation and to suppress the inflammatory
well as from multiple intestinal sites. Part of the
response within the GI tract.
liver and/or mesenteric lymph node biopsy, and
● Treatment typically involves dietary manage-
bile aspirated from the gall bladder can be sent for
ment, ± metronidazole, ± prednisolone.
culture.
● Treatment should be tailored to each patient.
● Collection of duodenal aspirates for quantitative
● Relapses warrant critical reassessment of the case,
culture may help to determine the bacterial load of
and often require repeated intensification of treat-
the small intestine.
ment and/or the addition of more potent immuno-
● Gastric biopsies should always be assessed for the
suppressive drugs.
presence of Helicobacter spp.
● Histopathology reveals inflammatory cells The diet should contain a single highly digestible
infiltrating the lamina propria, plus variable source of protein, ideally that the cat has not eaten before.
degrees of epithelial abnormality and glandular ● The diet should preferably contain few food addi-
distortion. tives, be gluten-free, lactose-free, low residue, not
– Lymphocytic-plasmacytic IBD is the most too high in fat, and adequately supplemented with
common form of IBD in the cat. It may occa- vitamins and minerals, especially B vitamins and
sionally progress to intestinal lymphosarcoma. potassium.
– Granulomatous enterocolitis is less common, ● High-fiber diets may help when the large bowel is
and often presents as GI obstruction. affected.
– Eosinophilic IBD is rare. It may be associated ● No other foods should be fed concurrently.
with eosinophilia and/or hypereosinophilic syn- ● During the initial phase of treatment, when the
drome where tissues other than the GI tract are bowel is recovering, it may be preferable to feed
also affected. either a home-cooked diet, a “sacrificial protein”
– Suppurative IBD is usually associated with an which the cat will then not be fed again, or protein
infectious etiology. hydrolysate which has reduced molecular weight
– Other forms also exist and many cats have mixed protein and is supposed to be less antigenic. This
populations of inflammatory cells. should be fed for 1–2 months, after which time the cat
● Unfortunately, when lymphangectasia is present, can then be fed a commercial “hypoallergenic” diet,
severe hypoproteinemia may render these patients a or further protein sources can be gradually reintro-
poor anesthetic and surgical risk. It may therefore be duced. If feeding homemade diets long-term, great
necessary to make a presumptive diagnosis based on care should be taken to ensure they are balanced.
the presence of diarrhea, panhypoproteinemia and
Metronidazole often forms the mainstay of treat-
lymphopenia in the absence of finding other diseases
ment. Its effect against anaerobic bacteria helps to
on hematology, serum biochemistry, fecal evalua-
reduce secondary bacterial overgrowth. It is also effec-
tion, abdominal ultrasound examination ± mucosal
tive against protozoa (e.g. Giardia spp.), has positive
biopsies.
effects on brush border enzymes levels, and is
believed to alter the immune function of the GI tract,
perhaps by altering neutrophil chemotaxis and inhibit-
Differential diagnosis ing cell-mediated immunity. Administer 7.5–15 mg/kg
PO q 8–12 hours for 2–4 weeks, then taper gradually
These include most of the other causes of weight loss
over 1–2 months. Some authors suggest that it is inad-
with a good appetite. However, since cats with IBD
visable to give very prolonged courses.
usually develop vomiting and/or diarrhea, other causes
of enteropathy, cholangiohepatitis, pancreatitis, Immunosuppressive agents:
hyperthyroidism and the other malassimilation syn- ● Immunosuppressive doses of corticosteroids are
dromes (including alimentary lymphosarcoma) should usually required. Administer prednisolone 2–4
be considered as important differentials. mg/kg q 12–24 hours PO, then taper over 1–3