The Level of Endotoxin in Organs, Antibiotic Sensitivity, and Serotyping of Bacteria Isolated from Cats and Dogs with Septicaemia

Septicaemia is the presence of bacteria and its toxins in blood circulation, potentially leads to sepsis and death. Despite its importance in human medicine, study pertaining to septicaemia in veterinary medicine has been lacking. The study was conducted to measure the concentration of endotoxin in vital organs and their relationship with point of entry of septicaemia in dogs and cats with septicaemia. Subsequently, common septicaemic agents and their sensitivity towards antibiotics were determined. Fifty carcasses of cats and dogs were selected. Samples of the heart, lungs, liver, and kidney were collected for bacterial identification and endotoxin concentration quantitation. The three most commonly isolated bacteria were subjected to antimicrobial sensitivity testing using disc diffusion technique. As Escherichia coli was later determined as the most common bacteria, the isolates were subjected to in silico serotyping. It was observed that E. coli, Klebsiella pneumoniae, and Staphylococcus pseudintermedius were the most commonly isolated bacteria in cats and dogs with septicaemia. Endotoxin was detected from all of the collected organs, with significantly (p<0.05) high concentration of endotoxin in lungs and kidney when septicaemia originated from the respiratory tract or urinary tract, respectively. These findings were consistent in both cat and dog. Escherichia coli were sensitive to sulfamethoxazole/trimethoprim and enrofloxacin, and resistant to clindamycin (intrinsic resistance), K. pneumoniae were observed to be resistant towards sulfamethoxazole/trimethoprim, clindamycin (intrinsic resistance), cephalexin, enrofloxacin, and amoxicillin (intrinsic resistance). On the other hand, S. pseudintermedius were sensitive towards all of the tested antibiotics. In silico serotyping of E. coli revealed high percentage of serotype O104:H4 and O102:H18 which were associated with infections in human. E. coli is the most commonly isolated bacteria and the gastrointestinal is the most common point of entry for septicaemia in cats and dogs. Common septicaemic agents of these companion animals showed sensitivity and resistance towards antibiotics commonly used in veterinary practice.