Chylothorax

A chylothorax is a type of pleural effusion. It results from lymphatic fluid accumulating in the pleural cavity.

Causes
Its cause is usually leakage from the thoracic duct or one of the main lymphatic vessels that drain to it. The most common causes are lymphoma and trauma caused by thoracic surgery. The effusion is characteristically white and milky in appearance and contains high levels of triglycerides.

In animals, chylothorax usually results from diseases that cause obstruction to the thoracic duct preventing lymph from draining normally into the venous system. Examples include tumors, heartworm disease, right sided cardiac failure, or idiopathic lymphangiectasia. The most effective form of treatment is surgical ligation of the thoracic duct combined with partial pericardectomy.

Differential Diagnosis

 * Cirrhosis
 * Congenital chylothorax
 * Filariasis
 * Iatrogenic
 * Idiopathic
 * Lymphoma
 * Nonlymphomatous malignancies
 * Nonsurgical penetrating trauma
 * Tuberculosis