Can serum amyloid A levels be used in the diagnosis of SIRS in cats with pyometra?

Serum amyloid A (SAA) level increases in conditions such as infection, tissue damage and trauma and is not specific to a disease but provides information about the presence and severity of inflammation. As a life-threating conditions pyometra usually causes systemic inflammatory response syndrome (SIRS) and therefore may lead an increase in SAA levels. The present study was designed to determine SAA levels in cats with pyometra that developed SIRS, and to demonstrate the diagnostic value of SAA by comparing it with hematological and biochemical parameters as well as SIRS criteria. For this purpose, data were used from cats with open-cervix pyometra (OP, n=6) and closed-cervix pyometra (CP, n=6), which were identified as having developed SIRS and were admitted to hospital as well as from healthy cats brought in for routine neutering, which were identified to be in the diestrus phase of the sexual cycle (DE, n=6). Cats with pyometra had higher SAA levels and leukocytosis compared to cats in the DE group (P= 0.002 and P= 0.000, respectively). The highest SAA level was detected in the CP group (168.6 µg/ml) and this level is statistically significant compared to the other groups (P= 0.028). While there was no correlation between SAA levels and SIRS criteria, SAA levels were negatively correlated with both AST (P= 0.045, rs=-0.478) and GGT (P= 0.019, rs= -0.548). In the study, it was determined that sepsis and SIRS progressed with different symptoms in cats and SIRS criteria were less specific in cats. It was concluded that SAA levels may be an important marker in closed-cervix pyometra cases. We think that the study data are promising but further and comprehensive studies are needed considering the number of patients included in the study.