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Clinical presentation, diagnosis and management of cholesterol effusions

John E Heffner, MD
Section Editor
V Courtney Broaddus, MD
Deputy Editor
Geraldine Finlay, MD


Cholesterol pleural effusions (also called chyliform effusion or pseudochylothorax) are uncommon and are usually seen in the setting of chronic pleural inflammation or infection of greater than five years duration, although shorter durations have also been reported [1-5]. By definition, they contain a high concentration of cholesterol, giving them their characteristic turbid or milky white appearance. Although similar in gross appearance, the milky-appearing fluid in a chylothorax contains a high concentration of triglycerides, most commonly from disruption or obstruction of the thoracic duct.

The diagnosis and management of cholesterol pleural effusions will be reviewed here. The etiology, clinical presentation, diagnosis, and management of chylothorax and general issues regarding the evaluation and management of pleural effusions are discussed separately. (See "Etiology, clinical presentation, and diagnosis of chylothorax" and "Mechanisms of pleural liquid accumulation in disease" and "Diagnostic evaluation of a pleural effusion in adults: Initial testing" and "Imaging of pleural effusions in adults".)


Cholesterol effusions and chylothoraces both classically have a milky or opalescent appearance. However, their etiologies and therapy differ, making it important to distinguish them.

Cholesterol effusions (also known as pseudochylothoraces or chyliform effusions) contain a high concentration of cholesterol. These effusions typically develop in patients with thickened and sometimes calcified pleural surfaces in the setting of chronic pleural inflammation [6,7], although they have been reported without pleural thickening in patients with rheumatoid arthritis [2,8].

Chylothoraces, by comparison, are much more common and contain a high concentration of triglycerides in the form of chylomicrons [1,9-11]. A chylothorax arises when lymph fluid from the thoracic duct or other lymphatic channels accumulates in the pleural space due to disruption or obstruction. (See "Etiology, clinical presentation, and diagnosis of chylothorax".)

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Literature review current through: Nov 2017. | This topic last updated: Jun 27, 2017.
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