Fecal S100A12 concentration predicts a lack of response to treatment in dogs affected with chronic enteropathy

S100A12 is a potential biomarker of gastrointestinal inflammation in dogs and fecal S100A12 concentrations are correlated with disease severity and outcome. The aim of the present study was to investigate whether there was any association between pre-treatment fecal S100A12 concentrations in dogs affected with chronic enteropathy (CE) and the response to treatment. Dogs affected with CE were recruited into the study and were classified as antibiotic-responsive diarrhea (ARD; n = 9), food-responsive diarrhea (FRD; n = 30) or idiopathic inflammatory bowel disease (IBD; n = 25). They were also grouped based on their response to treatment as complete remission (n = 35), partial response (n = 25) or no response (n = 4). Fecal S100A12 concentrations, measured by ELISA, were elevated in dogs affected with IBD compared with those from dogs affected with FRD (P = 0.010) or ARD (P = 0.025). Dogs with IBD that did not respond to treatment (n = 4) had significantly greater fecal S100A12 concentrations than dogs in complete remission (P = 0.009). Measurement of fecal S100A12 at the time of diagnosis discriminated between dogs with IBD that were refractory to therapy (≥2700 ng/g fecal S100A12) from those with at least a partial response (<2700 ng/g fecal S100A12), with a sensitivity of 100% and a specificity of 76%. These preliminary results suggest that testing of fecal S100A12 may be useful for predicting the lack of response to treatment in dogs affected with CE. The utility of serial fecal S100A12 measurements for monitoring dogs undergoing treatment for CE warrants further investigation.