The role of nutritional-immunological indices in estimating serum LPS and antioxidant enzyme activity and sepsis status in female dogs with pyometra caused by E. coli

The aim of this study was to diagnose pyometra and related sepsis status using cost-effective nutritional-immunological indices, antioxidants, and toxin levels in dogs and to investigate the utility of the indices in predicting toxin and antioxidant status. A total of 29 dogs were enrolled into the present study. Among these, 9 female dogs in their diestrus stages, were allocated for elective ovariohysterectomy. The pyometra group was also separated into two subgroups as Sepsis (+) and Sepsis (-). Blood samples were collected into two tubes containing EDTA for hematological analysis; without anticoagulant for serum progesterone, LPS concentration, and antioxidant levels at the time of diagnosis. Bacteriological and tissue samples of the uterus were collected after the ovariohysterectomy. Antioxidant activity, progesterone, and toxin concentration were determined by using commercial ELISA kits. Statistical analyses were performed using Stata version 16.1 and MedCalc 16 statistical software. Receiver operating characteristics curves were used for the threshold for evaluating pyometra and sepsis status. Pairwise comparisons were carried out of the area under the curve (AUC) for thresholds of nutritional immunologic indices (hemoglobin, albumin, lymphocyte, platelet (HALP) score; prognostic nutritional index (PNI); Albumin hemoglobin index (AHI)), serum LPS and antioxidant activity. Linear regression model was used for the estimation of serum LPS and antioxidant activity by using indices. Mean serum progesterone, LPS concentrations, and Nitric Oxide (NO) production were greater, while serum superoxide dismutase (SOD), tissue SOD, and glutathione peroxidase (GPx) activities were lower in dogs with pyometra. All nutritional-immunologic indices were lower in pyometra cases. Nutritional-immunologic indices (AUC of HALP:0.759; PNI:0.981; AHI 0.994), NO (AUC: 0.787) and SOD (AUC: 0.784) levels were useful for pyometra diagnosis. AHI and LPS were useful for the determination of sepsis status with the AUC values of 0.850 and 0.740, respectively. While AHI was useful for the estimation of serum LPS and NO concentration (p < 0.001), PNI was useful for serum SOD concentration (p = 0.003). In conclusion, PNI, HALP and AHI can be used in the diagnosis of pyometra, however, only AHI and LPS levels can be used in the diagnosis of sepsis. SOD and NO can be used to determine pyometra but have no effect on determining sepsis status. Additionally, the estimation of the levels of serum LPS, NO, and SOD activities can be done using the AHI and PNI values.