S100A12 and myeloperoxidase (MPO) are considered inflammatory markers of chronic enteropathy (CE) and mainly originate from granulocytes. Increased concentrations of canine S100A12 (cA12) in feces and serum were found in dogs with CE. Intestinal mucosal MPO activities have been reported to be increased in humans with inflammatory bowel disease (IBD) and also in animal models of human IBD. However, intestinal mucosal cA12 and MPO have not been investigated in dogs with CE.

We evaluated the levels of mucosal cA12 and MPO in dogs with CE in comparison with healthy dogs using an enzyme-linked immunoassay and a spectrophotometric method, respectively. Additionally, we assessed the association of mucosal cA12 and MPO levels with the canine clinical IBD activity index (CIBDAI), histopathologic findings, clinical outcome, and serum albumin concentration. Intestinal mucosal biopsies were collected from 40 dogs with CE (duodenum [n=35], ileum [n=12], colon [n=15], and caecum [n=6]). Historical intestinal tissue samples from 18 healthy beagle dogs served as controls (duodenum, ileum, and colon [n=18, each] and caecum [n=6]). Data are presented as medians (interquartile range).

In comparison to healthy controls, mucosal cA12 concentrations in CE-dogs were higher in duodenum (43.93 [23.62–78.03] vs. 11.86 [7.66–29.1] µg/L; p<0.0001) and colon (63.04 [33.53–211.53 vs. 15.94 [6.95–59.3] µg/L; p<0.001] µg/L). Mucosal MPO activities of CE-dogs were higher than in control dogs in duodenum (1.3 [0.77–2.16] vs. 0.41 [0.11–0.64] ΔA/min; p<0.0001), ileum (1.91 [0.72–2.83] vs. 0.75 [0.21–1.27] ΔA/min; p<0.01), colon (1.46 [0.57–3.01 vs. 0.09 [0.03–0.17] ΔA/min; p<0.0001] ΔA/min), and caecum (0.68 [0.3–1.55] vs. 0.19 [0.08–0.4] ΔA/min; p<0.05).

Mucosal cA12 concentrations showed a significant association (p<0.05) with severity of macrophage infiltration in the duodenum and total histopathologic injury and epithelial injury in the colon. Mucosal MPO activities showed a significant association (p<0.05) with severity of total histopathologic injury, epithelial injury, and eosinophil infiltration in the duodenum. Duodenal cA12 concentrations showed a strong negative correlation with serum albumin concentration (rs=Ë-0.449; p=0.007). There was no significant association between mucosal cA12 and MPO levels with CIBDAI or clinical outcome.

This study showed that both mucosal cA12 concentrations and MPO activities are increased in the duodenum and colon of dogs with CE, with mucosal MPO being also increased in the ileum and caecum. The results provide supporting evidence for the possible diagnostic value of cA12 and MPO for dogs with CE.

Disclosures

No disclosures to report.