Nontraumatic Chylothorax: Diagnostic Algorithm and Treatment Options.

Nontraumatic chylothorax is a relatively rare condition in which the intestinal lymph (chyle) leaks into the pleural cavity. Nontraumatic chylothorax is more difficult to treat than the more common traumatic chylothorax because the site of chylous leak may occur in less predictable locations. In the past, patients with nontraumatic chylothoraces were offered traditional fluoroscopically guided lymphangiography and thoracic duct embolization similar to traumatic chylothorax. However, the observation that thoracic duct embolization outcomes for nontraumatic chylothorax differed based on the imaging findings during lymphangiography has led to the development of a treatment algorithm, which incorporates noninvasive diagnostic studies, such as magnetic resonance lymphangiography. The development of this systematic approach allows better delineation of the source of the chylous leak and selection of the appropriate method of embolization. In this article, we will review the etiologies of nontraumatic chylothorax, the diagnostic work-up for managing this condition, and the treatment algorithm to care for these patients.