Increased concentrations of Serum amyloid A in dogs with sepsis caused by pyometra

BACKGROUND: Sepsis is a serious and potentially life-threatening condition and early diagnosis and appropriate treatment is crucial for survival. Pyometra is one of the most common diseases in intact female dogs. The disease often leads to sepsis (systemic inflammatory response syndrome, SIRS, caused by infection). Diagnostic markers for detecting sepsis are gaining increasing interest in veterinary medicine. Acute phase proteins (APPs) such as C-reactive protein (CRP) are useful for detecting systemic inflammation in dogs. Serum amyloid A (SAA) is another major APP in dogs that is not yet as widely used. Albumin is regarded as a negative APP and has earlier been evaluated for prediction of prognosis in septic dogs. The aim of the present study was to determine SAA, CRP and albumin concentrations in dogs with sepsis and pyometra and to evaluate whether these inflammatory markers are associated with length of postoperative hospitalization. RESULTS: Thirty-one surgically treated bitches with pyometra were included, whereof 23 septic (SIRS-positive) and eight non-septic (SIRS-negative). Albumin concentrations were analyzed by routine automated methods. SAA and CRP analyses were performed with previously validated commercially available assays (ELISA and immunoturbidimetric). Mean (±SE) serum concentrations of SAA were significantly higher in septic (130.8 ± 8.0 mg/L) compared to non-septic bitches (88.5 ± 12.5 mg/L). Using a cut-off value for SAA of 109.07 mg/L (n = 31 bitches), the sensitivity and specificity for detecting sepsis was 74% and 50%, respectively. Serum albumin concentrations were not significantly different in septic compared to non-septic bitches (mean ± SE, 25 ± 1 g/L and 26 ± 1 g/L, respectively). CRP concentrations were also not significantly different in septic (mean ± SE 225.6 ± 16.0 mg/L) compared to non-septic bitches (mean ± SE, 176.0 ± 27.1 mg/L). None of these inflammatory markers were associated with the outcome as measured by length of hospitalization. CONCLUSIONS: SAA concentrations were increased in dogs with sepsis induced by pyometra and may be useful as an adjunctive diagnostic marker for sepsis. To evaluate the full potential of SAA as a marker for sepsis also in other diseases, further studies are warranted.