Most cat owners and many colleagues may consider that regular vomiting is “normal” in a cat. Yet cats who vomit more than twice a month should be worked up rather than treated with “benign neglect.” Statistically, about half have chronic enteritis and about half have intestinal cancer. Such is the revolutionary conclusion of a retrospective study* conducted on 300 cats by Gary Norsworthy at the Alamo Feline Health Center in San Antonio, TX. Cats were suspected to have chronic small bowel disease, which leads to chronic vomiting, chronic diarrhea and weight loss.
The objective of the study was to determine the prevalence of suspected cats having small bowel disease based on clinical signs and ultrasonographic findings; to identify the most common causes; and to compare the methods for differentiating the various causes of small bowel disease.
- Vomiting ≥3 times/months for at least 3 consecutive months
- Small bowel diarrhea for ≥3 weeks
- Weight loss of ≥1 lb within the past 6
Wall thickness is defined as the distance from the serosa to the near side of the lumen. Laparotomy and small intestine biopsy were recommended if the wall thickness was ≥3 mm or if ≥2 measurements were ≥28 mm. Cats with some measurements of wall thickness ≥28 mm and other measurements of wall thickness ≤25 mm were categorized as having segmental disease.
Biopsy results were classified as lymphoma, chronic enteritis, non-lymphoid neoplasia, other, or normal. If biopsies of an individual cat showed different categories, the disease was classified as segmental.
Of the 300 cats, 159 (53%) were male and 141 (47%) were female. Median age was 11 years (1-19 years) with 141 (47%) ≥12 years old and 81 (27%) ≥14 years old. All 300 cats recovered fully from the surgery.
Overall, 288 (96%) had abnormalities where 150 (50%) had chronic enteritis, 124 (41%) lymphoma, 11(4%) non-lymphoid neoplasia and 3 had other conditions. The remaining 12 (4%) were normal.
The authors concluded:
- Chronic small bowel disease was diagnosed in 96% of affected cats.
- 45% had intestinal cancer (primarily lymphoma) and 50% had chronic enteritis.
- Full-thickness (surgical) biopsies of the intestine gave the diagnosis. Ultrasound alone could not differentiate between lymphoma and chronic enteritis.
* GD Norsworthy et al. “Prevalence and underlying causes of histologic abnormalities in cats suspected to have chronic small bowel disease: 300 cases (2008-2013).” JAVMA 2015, Vol. 247, N. 6, p. 629-635.