Bicavitary septic effusion associated with staphylococcal cholecystitis in a dog

Septic peritonitis and septic pyothorax are both common life-threatening conditions in veterinary medicine. To the authors' knowledge, this is the first report describing septic bicavitary effusion associated with a biliary staphylococcal infection in a dog. The exact mechanism by which the infection spread remains unclear, but hematogenous or lymphatic routes are considered the most probable. However, the presence of microscopic diaphragmatic defects and an anicteric gallbladder rupture cannot completely be excluded. The concurrent hyperadrenocorticism may have also contributed to an immunocompromised state, predisposing the dog to the development of infection.