Objective—To assess and compare the expression of perinuclear antineutrophilic cytoplasmic antibodies (pANCA) in sera obtained from dogs with inflammatory bowel disease (IBD) and dogs with intestinal lymphoma.
Animals—104 dogs with IBD and 23 dogs with intestinal lymphoma.
Procedures—Each ill dog had persistent gastrointestinal signs (> 3 weeks in duration) and absence of response to diet changes or antimicrobial treatments. Gastrointestinal endoscopy was performed in ill dogs to obtain intestinal biopsy specimens for histologic confirmation of IBD or lymphoma. A serum sample was obtained from each ill dog. Neutrophils were isolated from a blood sample from the healthy dog; neutrophil-bearing slides were incubated with serum from each ill dog and examined for expression of pANCA by use of an indirect immunofluorescence technique. Detection of cells that had a perinuclear fluorescence pattern was considered a positive result.
Results—The 2 groups of dogs did not differ with regard to breed and sex but did differ with regard to age. Expression of pANCA was detected in 38 of the 104 (36.5%) dogs with IBD and 4 of the 23 (17.4%) dogs with intestinal lymphoma. Although the frequency of pANCA expression was higher in dogs with IBD, compared with findings in dogs with intestinal lymphoma, the difference was not significant.
Conclusions and Clinical Relevance—Results indicated that circulating pANCA are present in some dogs with IBD or intestinal lymphoma. However, pANCA detection does not seem to be useful for distinguishing dogs with IBD from dogs with intestinal lymphoma.