Canine pleural and mediastinal effusions: a retrospective study of 81 cases

Abstract

Eighty-one cases of canine pleural and/or mediastinal effusions were identified from radiography and ultrasonography records reviewed between 1992 and 2000 at the Queen's Veterinary School Hospital, University of Cambridge. All cases had a follow-up period of at least 12 months. Twenty-eight underlying disease processes were associated with pleural and/or mediastinal effusions. The most common disease was pyothorax (13 cases). Other common diseases identified were idiopathic pericardial effusion, cranial mediastinal mass, idiopathic chylothorax, secondary lung metastases and dilated cardiomyopathy. Approximately one-quarter of all cases recovered completely after initial treatment and one-third of all cases either died during, or were euthanased immediately after, completion of the initial investigations.

Successful medical treatment of 15 dogs with pyothorax

“…Although pyothorax is not considered a common condition in dogs, it has been documented to be one of the more common causes of pleural effusion in dogs in one study (Mellanby and others 2002). The cause is often unknown, although inhaled foreign body migration is suspected most frequently.…”

Body Cavity Fluids

“…Historically, chylous effusions were thought to be primarily a result of thoracic duct rupture. Purebred cats were overrepresented in a 1991 retrospective study by Fossum et al Chylous pleural effusions are more prevalent in cats (30.5%) than dogs (18.9%) (Davies and Forrester, 1996;Mellanby et al, 2002); however, the prevalence of chylothorax in the Mellanby study may be underestimated as mediastinal effusions were also included in that study. Causes for chylous effusions in the thoracic cavity include cardiovascular disease, neoplasia (e.g., lymphoma, thymoma, and lymphangiosarcoma), heartworm disease, diaphragmatic hernia (Kerpsack et al, 1994), lung torsion, mediastinal fungal granulomas, chronic coughing, vomiting, primary lymphedema, iatrogenic, or idiopathic Fossum et al, 1986a;Fossum et al, 1991;Fossum, 1993;Mclane and Buote, 2011;Meakin et al, 2013;Neath et al, 2000;Schuller et al, 2011;Singh and Brisson, 2010;Small et al, 2008;Waddle and Giger, 1990).…”

“…Hemothorax is associated with a variety of etiologies (Mellanby et al, 2002). In the dog these include rodenticide intoxication (DuVall et al, 1989), neoplasia (Slensky et al, 2003), secondary to parasitic infestation (Chikweto et al, 2012;Sasanelli et al, 2008), and iatrogenic (Cohn et al, 2003).…”

Thoracoscopic foreign body removal and right middle lung lobectomy to treat pyothorax in a dog

“…Pyothorax, characterised by the presence of a pleural exudate (whether it be septic or not), is a common cause of pleural effusion (Mellanby and others 2002) and a life‐threatening disease in dogs.…”