LAUSR

OBJECTIVE To quantify plasma cytokine concentrations in dogs with sepsis and noninfectious systemic inflammation and to evaluate the association between plasma cytokines and outcome in dogs with sepsis. DESIGN Prospective, observational cohort study. SETTING University teaching hospital. ANIMALS Forty-five dogs with sepsis, 10 dogs with noninfectious systemic inflammation (nSIRS), and 15 healthy controls were consecutively enrolled from June 2015 to February 2016 and followed to hospital discharge. Dogs with sepsis satisfied ≥2 SIRS criteria and had a documented or highly suspected bacterial infection. Dogs with nSIRS satisfied ≥2 SIRS criteria but had no evidence of infection. Dogs <3 kg and those with documented coagulopathy were excluded. INTERVENTIONS Measurement of inflammatory cytokines and high-mobility group box-1 (HMGB-1) was performed on each group. MEASUREMENTS AND MAIN RESULTS High-mobility group box-1 concentrations were analyzed by ELISA. Plasma concentrations of 13 cytokines were measured in singlet using multiplex magnetic bead assays. Kruskal-Wallis with Dunn's multiple comparison tests were used to compare biomarker concentrations between groups. Mann-Whitney U-tests were used to compare biomarker concentrations between survivors and nonsurvivors. Associations between biomarkers were evaluated using Spearman's correlation coefficients. Independent outcome predictors were identified using multivariable logistic regression. Alpha was set at 0.05. Concentrations of interleukin (IL)-6, C-X-C motif chemokine (CXCL)-8, keratinocyte-derived chemokine (KC)-like, C-C motif chemokine ligand 2 (CCL2), and HMGB-1 were significantly greater in dogs with sepsis versus healthy controls (all P ≤ 0.034). In dogs with sepsis, only CCL2 was independently associated with survival (odds ratio [OR] 0.996, 95% CI 0.993-0.999, P = 0.004). A cut-off of 385 pg/mL for CCL2 was 80% sensitive and 91.4% specific for nonsurvival (area under the ROC curve [AUROC] 0.866). CONCLUSIONS Dogs with sepsis have significantly increased concentrations of HMGB-1 and inflammatory cytokines, including IL-6, CXCL8, and KC-like. Increased CCL2 concentration is a negative prognostic indicator in dogs with sepsis. These findings should be confirmed using duplicate analyses in larger, distinct populations of dogs with sepsis before applying them to clinical patients.