Kinetics of Regenerating Protein 3E and C‐Reactive Protein in Healthy Dogs, Dogs Undergoing Tibial Plateau Leveling Osteotomy, and Dogs With Sepsis

BACKGROUND: Serial measurements of acute-phase proteins help monitor the development of and recovery from sepsis in people and dogs. To date, the kinetics of regenerating protein (REG) 3E, a novel biomarker for inflammation in dogs, are unknown. OBJECTIVES: The goal of our study was to assess changes in the concentrations of REG3E and compare these to C-reactive protein (CRP) concentrations over 48-72 h in different cohorts of dogs. METHODS: Plasma REG3E concentrations were measured using an ELISA on 3-4 consecutive days from 43 dogs, including 12 healthy controls, 17 undergoing tibial plateau leveling osteotomy (TPLO), and 14 with sepsis. Canine CRP was measured using a turbidimetric immunoassay. RESULTS: REG3E concentrations were low in control and TPLO dogs throughout all time points. In the TPLO group, there was a mild but significant increase in CRP over time. REG3E and CRP concentrations were higher in septic dogs at admission compared to the other groups and progressively decreased after initiation of treatment to 14% and 28% of initial levels, respectively, within 72 h. REG3E, but not CRP concentrations, stayed high in two dogs, one of which developed recurrent sepsis. There was a significant moderate correlation between both acute-phase proteins among all groups and within the sepsis group, but not within the TPLO group. CONCLUSIONS: In conclusion, based on this cohort of dogs, CRP appears to be more sensitive to detect minor postsurgical inflammation, but the potential of REG3E to predict developing or recurrent sepsis deserves further investigation.