A Retrospective Study on Bacteriology, Clinicopathologic and Radiographic Features in 28 Cats Diagnosed with Pyothorax

Abstract

This retrospective study aimed to determine the etiological, clinicopathological, and radiographic features and outcome of feline pyothorax cases. Medical records from twenty-eight cats with pyothorax aged from 4 months to 10 years (median 10 months) diagnosed between 2013 and 2020 were reviewed. Dyspnoea (75.0%), abnormal lung sounds (75.0%) and open-mouth breathing (64.3%) were the predominant respiratory signs. Leucocytosis (61.5%), particularly monocytosis (68.0%), and hyperglobulinaemia (65.4%) were among the most prominent findings in blood analysis. Bilateral pleural effusion was found in 67.9% of the thoracic radiographs. A total of 47.4% of the cytological samples revealed the presence of bacteria, while all had positive bacterial growth. Pasteurella multocida, E. coli, Streptococcus spp., and Staphylococcus spp. were the predominant aerobic bacteria isolated from pleural effusion samples. A chest tube was placed in 64.3% of the cats and 66.7% of cats with chest tubes survived. In total, 46.4% of cats with pyothorax recovered. Amoxicillin–clavulanate was the antimicrobial of choice against aerobic bacteria found in this study and should be given in combination with antimicrobials that cover anaerobic bacteria. Chest tube placement is crucial for treatment success. Cytological results and bacterial culture may not be consistent; thus, bacterial culture should be performed for every case.

Therapy of Pyothorax in Cats via Small-Bore Thoracostomy Tube in Terms of Efficacy, Complications and Outcomes

“…Parenteral antibiotics are recommended as a starting point, while their administration into the pleural cavity is no longer recommended [ 12 ]. In addition, in most studies a closed-chest lavage is performed [ 1 , 2 , 3 , 4 , 5 , 6 ], which is also recommended in the current guidelines [ 12 ].…”

“…The overall prognosis for cats with pyothorax is fair to good. Cats survive to discharge in 46% to 78% of cases [ 1 , 2 , 3 , 4 , 5 ]. The mortality rate is highest during the first 48 h of hospitalisation [ 1 , 2 , 6 ].…”

“…A combination of drainage of the septic pleural effusion via thoracostomy tubes and intravenous (IV) administration of a broad-spectrum antibiotic is currently the first-line treatment. Surgical management is recommended in 4% to 6% of cases because of intrathoracic abscesses [ 1 , 2 , 5 ] detected by diagnostic imaging and in 5% to 9% of cases because medical management fails [ 1 , 2 , 3 , 4 ].…”

“…For medical management, single or multiple thoracentesis or placement of a thoracostomy tube with and without intermittent closed-chest lavage are described [ 1 , 2 , 3 , 4 ]. Traditionally, large-bore thoracostomy tubes (14–16 F) are placed with a rigid trocar under anaesthesia [ 4 , 5 , 7 ]. Complications associated with large-bore thoracostomy tubes in cats with pyothorax include anaesthetic complications, pneumothorax, lung laceration and subcutaneous fluid leakage [ 4 , 5 ].…”

“…Traditionally, large-bore thoracostomy tubes (14–16 F) are placed with a rigid trocar under anaesthesia [ 4 , 5 , 7 ]. Complications associated with large-bore thoracostomy tubes in cats with pyothorax include anaesthetic complications, pneumothorax, lung laceration and subcutaneous fluid leakage [ 4 , 5 ].…”