Serum alpha -proteinase inhibitor concentrations in dogs with systemic inflammatory response syndrome or sepsis.

OBJECTIVE

To determine whether the concentration of serum canine alpha -proteinase inhibitor (cα -PI) has diagnostic or prognostic utility in dogs with sepsis or noninfectious systemic inflammatory response syndrome (SIRS).

DESIGN

Prospective, observational study from May to December 2010.

SETTING

University teaching hospital ICU.

ANIMALS

Sixty-nine client-owned dogs: 19 dogs with SIRS or sepsis and 50 healthy control dogs.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Serum and plasma samples were collected from dogs with SIRS or sepsis on the day of hospital admission and once on the following 2 days, and on a single day in healthy controls. Patients were assessed using the 10-parameter Acute Patient Physiologic and Laboratory Evaluation (APPLE ) and 5-parameter (APPLE ) score. Serum cα -PI concentrations were measured, compared among groups of dogs, and evaluated for a correlation with the concentration of serum C-reactive protein, plasma interleukin-6, tumor necrosis factor-α, the APPLE scores, and survival to discharge. Serum cα -PI concentrations were significantly lower in dogs with SIRS/sepsis (P < 0.001) than in healthy controls. While day 1 serum cα -PI concentrations did not differ between dogs with SIRS and those with sepsis (P = 0.592), septic dogs had significantly lower serum cα -PI concentrations on days 2 (P = 0.017) and 3 (P = 0.036) than dogs with SIRS. Serum cα -PI concentrations did not differ between survivors and nonsurvivors (P = 1.000), but were inversely correlated with the APPLE score (ρ = -0.48; P = 0.040) and plasma interleukin-6 concentrations (ρ = -0.50; P = 0.037).

CONCLUSIONS

These results suggest a role of cα -PI as a negative acute phase protein in dogs. The concentration of serum cα -PI at the time of hospital admission does not have utility to identify dogs with sepsis from those with noninfectious SIRS, but may be a useful surrogate marker for early stratification of illness severity.