Lymphoma is the most common malignant cause, representing about 60% of all cases, with the non-Hodgkins variant being the most prevalent. Traumatic injuries to the upper abdomen and chest including those sustained during surgery are the second leading cause of chylothorax, accounting for approximately PD0325901 mw 25% of cases. The first traumatic injury to the thoracic duct was described in 1875 and the first thoracic duct ligation

was performed in 1948 [6]. The traumatic causes of injury to the duct vary widely, and the most common blunt mechanism producing injury is related to sudden hyperextension of the spine with rupture of the duct just above the diaphragm [4, 7–9]. Sudden selleck stretching over the vertebral bodies for any reason may tear the duct, but this usually occurs in the setting of a thoracic duct previously affected by disease [4, 8]. Episodes of vomiting or a violent bout of coughing resulting in shearing of the lymphatic conduit along the crux of the right diaphragm has been reported as well

[9]. Penetrating injuries, from a gunshot or stab wound, are less common and usually associated with severe damage to nearby structures. The pertinent anatomy involved in the development of a chylothorax begins with the cysterna chyli, which is a confluence of lymphatics located in the retroperitoneum, just to the right of the posteromedial aorta at the level of the renal

arteries. The thoracic duct ascends from this level and enters the chest through the aortic hiatus into the right hemithorax. The duct crosses over to the left chest at the fourth and fifth thoracic levels and enters the neck anterior to the left subclavian artery to join the venous system at the junction of the left subclavian vein and left internal jugular vein [10, 11, 13]. Knowledge of this anatomy should alert the physician to the possibility of a thoracic duct injury with thoracic spine fractures or any associated upper abdomen or chest injury involving this trajectory. As in this case, the diagnosis of a chyle leak was supported by a pleural fluid triglyceride level greater than 110 mg/dL. A pleural fluid triglyceride concentration less Progesterone than 50 mg/dL excludes a chylothorax. An intermediate level between 50 and 110 mg/dL should be followed by lipoprotein analysis to inspect the pleural fluid for chylomicrons or cholesterol crystals. The presence of chylomicrons and the absence of cholesterol crystals confirm a chyle leak. In addition, a ratio of pleural fluid cholesterol to triglyceride of less than 1 is also diagnostic [11, 12]. Although most cases of traumatic chylothorax can be managed non-operatively, the need for surgical intervention in the subset of patients with associated thoracic fractures is higher and approaches 50 percent [5, 11].