Acute phase protein response and changes in lipoprotein particle size in dogs with systemic inflammatory response syndrome

Abstract

Background: Improved methodology to measure acute phase proteins and determination of lipoprotein particle-size distribution (PSD) could be clinically useful in dogs with systemic inflammatory processes. Objectives: Evaluate an immunoturbidometric assay for serum amyloid A (SAA) and lipoprotein PSD in dogs with sepsis, nonseptic systemic inflammation, and in healthy controls. Correlate dyslipidemic changes with SAA and C-reactive protein (CRP) concentrations. Animals: Twenty-five dogs with sepsis, 15 dogs with nonseptic systemic inflammation, and 22 healthy controls. Methods: Prospective, case-control study. Variables included SAA, CRP, and electrophoretic subfractionation of high- and low-density lipoproteins (HDL, LDL). Continuous variables were compared using ANOVA or Kruskal-Wallis tests with linear regression or Spearman's rank correlation used to assess relationships between variables. Results: Median SAA and CRP concentrations were greater in dogs with sepsis (SAA 460 mg/L, interquartile range [IQR] 886 mg/L; CRP 133.2 mg/L, IQR 91.6 mg/L) and nonseptic inflammation (SAA 201 mg/L, IQR 436 mg/L; CRP 91.1 mg/L, IQR 88.6 mg/L) compared to healthy dogs (SAA 0.0 mg/L, IQR 0.0 mg/L; CRP 4.9 mg/L, IQR 0.0 mg/L) P 677.5 mg/L SAA was 43.2% sensitive and 92.3% specific for sepsis. Low-density lipoprotein was higher in dogs with sepsis 29.6%, (mean, SD 14.6) compared to 14.4% (mean, SD 5.6) of all lipoproteins in healthy controls (P =.005). High-density lipoprotein was not associated with CRP but was negatively correlated with SAA (rs −0.47, P