Spontaneous bilateral extrapleural hematoma: a case report.

Extrapleural hematoma (EPH) is a rare condition characterized by the accumulation of blood in the extrapleural space. EPH is generally identified by computed tomography (CT), which shows an inward displacement of extrapleural fat due to intrathoracic peripheral fluid accumulation (Ann Ital Chir 75(83): 5, 2004; J Korean Radiol Soc 49: 89-97, 2003; Monaldi Arch Chest Dis 63(3): 166-169, 2005). EPH has been reported to be associated with chest trauma and injuries. However, the correlation between hemodialysis and EPH has not yet been reported. The causes of EPH in a hemodialysis patient have been postulated, which include high venous flow through the arteriovenous fistula that results in an increase in venous pressure stenosis and/or thrombosis of the brachiocephalic and/or subclavian veins. These conditions thereby induce an increase in venous pressure in the intercostals and bronchial veins of the chest. Pleural fluid resorption is rare and excess pleural fluid formation commonly occurs (J Thoracic Imaging 26(3): 218-223, 2011). The occurrence of pleuritis with fusion of the two pleuric layers results in hematoma development in the extrapleural space instead of the pleural space. We present a chronic hemodialysis patient with spontaneous unilateral EPH. The progression to bilateral EPH was noted after VATS procedure. Awareness of EPH and the use of conservative management are key points for the treatment of this rare clinical condition.