Histopathologic examination of the gastric biopsy samples showed no marked inflammation. Moderate numbers of large Helicobacter species-like organisms were present within the gastric pits and extended into the gastric glands. The results of a urease
test were positive, suggesting the presence of Helicobacter species. The duodenal samples showed moderate to severe lymphocytic-plasmacytic infiltrates within the mucosal lamina propria
with mild central lacteal dilatation. This histopathologic report confirmed a diagnosis of IBD.
Treatment and follow-up
The dog was given oral folate supplementation (10 µg/kg) once a day and cobalamin (400 µg) subcutaneously once a week for
six weeks and then every other week for six weeks. Folate and cobalamin concentrations were to be evaluated one week after
the last cobalamin dose. The clinical importance of Helicobacter species in the stomach of dogs and cats is still controversial. The bacteria may even be a normal inhabitant of the stomach.
The Helicobacter species infection was treated in this case because of the gross changes seen on endoscopic examination. This treatment included
amoxicillin (20 mg/kg orally b.i.d.), metronidazole (17 mg/kg orally b.i.d.), famotidine (1.3 mg/kg orally once a day), and
bismuth subsalicylate (1 ml/kg orally one to three times a day) for two weeks. The dog's diet was also changed to a novel
protein diet (Prescription Diet Canine z/d Ultra—Hill's).
The patient did not respond well to therapy initially. After about six weeks, the owner reported that the dog still had a
poor coat and poor claw integrity with minimal weight gain. The necessary duration of a novel protein diet is controversial.
Clinical improvement may not occur until 10 to 13 weeks after beginning such a diet. However, some clinicians think that substantial
improvement should occur within four to six weeks. In one study, 95% of dogs were clinically better within three weeks.2 Prednisone was initiated (2.7 mg/kg/day for four to six weeks, gradually tapered every three or four weeks) because there
was no improvement with empirical deworming and six weeks of a diet trial. The metronidazole, famotidine, bismuth subsalicylate,
and special diet were continued. The dog quickly improved once it began receiving the prednisone.
Over the subsequent five months, the dog gained weight and had no further claw problems and a much improved coat. The owner
reported that the dog was doing great. It was maintained on prednisone (0.6 mg/kg) once a day. The owner was encouraged to
continue tapering the prednisone because it is important to find the lowest effective dose.
Discussion
This case is an interesting example of IBD because the gastrointestinal signs were intermittent and relatively unnoticed by
the owner, yet the disease was serious enough to cause malnutrition, which manifested as weak, breaking claws; a poor coat;
and stunted growth. IBD is a general term that represents several chronic gastrointestinal disorders characterized by inflammatory infiltrates in
the mucosa of the gastrointestinal tract. Diagnosis is based on excluding systemic diseases (e.g. hypoadrenocorticism) and other known causes of intestinal inflammation (e.g. parasites, dietary intolerance or sensitivity) and detecting inflammatory cell infiltrates on histopathologic examination
of intestinal biopsy samples. The most common infiltrates are lymphocytes and plasma cells or eosinophils.3
The clinical findings are variable and may include anorexia, intermittent diarrhea, and vomiting in mild cases to intractable
small intestinal diarrhea, weight loss, and vomiting in severe cases. The treatment of IBD is based on the severity of clinical
and pathologic findings and usually consists of a combination of a novel protein diet, antibiotics, and immunosuppressive
therapy. Empirical deworming with a broad-spectrum product (e.g. fenbendazole) and a dietary trial with a highly digestible diet (e.g. Eukanuba Low-Residue Formula—Iams) or a novel protein source should yield results within six weeks if parasites or dietary
intolerance or sensitivity is present. Additionally, a therapeutic trial for antibiotic-responsive enteropathy or small intestinal
bacterial overgrowth may be warranted.
Immunosuppressive agents are often required in patients that do not respond to these treatments alone or that have hypoproteinemia
or moderate to severe infiltrates. Oral prednisone (2 to 4 mg/kg/day orally) is the initial drug of choice. It is important
to obtain biopsy samples before immunosuppressive corticosteroid administration. Diagnosis and treatment of lymphoma may be
hindered by prior corticosteroid use, and corticosteroids may be fatal in cases of fungal disease.
Kristin Crass, DVM Department of Medical Sciences School of Veterinary Medicine University of Wisconsin Madison, WI 53706
REFERENCES
1. Scott, D.W. et al.: Diseases of eyelids, claws, anal sacs, and ears. Muller & Kirk's Small Animal Dermatology, 6th Ed. W.B. Saunders, Philadelphia, Pa., 2001; pp 1185-1232.
2. Groh, M.; Moser, E.: Diagnosis of food allergy in the non-seasonally symptomatic dog using a novel antigen, low molecular
weight diet: A prospective study of 29 cases. J. Vet. Allergy Clin. Immunol. 6 (1):5; 1998.
3. Guilford, W.G. et al.: Idiopathic inflammatory bowel diseases. Strombeck's Small Animal Gastroenterology, 3rd Ed. W.B. Saunders, Philadelphia, Pa., 1996; pp 451-486.
SUGGESTED READING
1. Simpson, K.: Chronic enteropathies: How should I treat them? Proc. ACVIM, ACVIM, Lakewood, Colo., 2003.
2. Stone, M.: Is It IBD? Proc. Tufts Animal Expo, Boston, Mass., 2002.
3. Jergens, A.E.: Inflammatory bowel disease in the dog and cat. Proc. WSAVA, World Small Animal Veterinary Association, Granada, Spain, 2002.
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