Detection of pathogens in blood or feces of adult horses with enteric disease and association with outcome of colitis

Abstract Background Rates of detecting ≥1 potential enteric pathogens (PEP) or toxins (PEP‐T) in feces, blood, or both of horses ≥6 months of age with enteric disease and impact of multiple detections on outcome of horses with colitis has not been reported. Objective To determine detection rates of PEP/PEP‐T in feces, blood, or both of horses with enteric disease and effect of detecting multiple agents on outcome of horses with colitis. Animals Thirty‐seven hundred fifty‐three fecal samples submitted to IDEXX Laboratories and 239 fecal and blood samples submitted to Michigan State University's Veterinary Diagnostic Laboratory (MSUVDL). Methods Retrospective evaluation of PEP/PEP‐T testing results was performed to determine rates of detection of 1 or more PEP/PEP‐T. Impact of detecting multiple agents on outcome was assessed in 239 horses hospitalized for colitis. Results One or more PEP/PEP‐T was detected in 1175/3753 (31.3%) and 145/239 (60.7%) of samples submitted to IDEXX Laboratories and MSUVDL, respectively. In a hospitalized cohort, survival to discharge was lower (76%) in horses with 1 agent, compared to horses with either no (88%) or multiple (89%) agents. There was no difference (P = .78) in days of hospitalization between horses with 0 (1–17), 1 (1–33), and > 1 positive (1–20) result. There was no difference in cost of hospitalization (P = .25) between horses with 0 ($2357, $1110‐15 553), 1 ($2742, $788‐11 005), and >1 positive ($2560, $1091‐10 895) result. Conclusions and Clinical Importance Detection rates of PEP/PEP‐T in horses with colitis vary with cohorts and tests performed. Detection of more than 1 PEP or PEP‐T did not affect outcome.