Gastrointestinal: Black pleural effusion induced by pancreaticopleural fistula

Abstract

A 47-year-old woman with chronic alcoholic pancreatitis presented to our emergency department with progressive dyspnea that persisted for one month. She was afebrile, but tachypneic (30 breaths/ min). Physical examination revealed decreased breath sounds and dullness to percussion over the left hemithorax. Blood tests showed leukocytosis (White blood cell: 17,830/μL) and elevated amylase (508 IU/L) and lipase (1,284 IU/L). The chest X-ray (Figure 1a) and ultrasonography revealed massive left-sided pleural effusion. Emergency thoracentesis yielded large amount of black, positive occult-blood and amylase rich (53,600 IU/L) exudative fluid (Figure 1b). Microscopic analysis of pleural fluid indicated severe hemolysis. Subsequent enhanced thoracoabdominal computed tomography revealed an atrophic pancreas with parenchymal calcifications (Figure 2a) and a fistulous tract arising from an encapsulated cystic lesion in the tail of pancreas (Figure 2a, arrow) which tracked alongside the left crus of diaphragm (Figure 2b, arrow) and passed through the aortic hiatus (Figure 2c, arrow) into the pleural cavity (Figure 2d, arrow). Black pleural effusion induced by a pancreaticopleural fistula was diagnosed. Because this patient declined surgical management, she received conservative treatment with thoracic drainage. However, her condition deteriorated and she died 2 months after admission. Pancreaticopleural fistula, an unusual complication of chronic pancreatitis, results from a disruption of the pancreatic duct or a pseudocyst which leaks the pancreatic fluid through the retroperitoneum into the pleural cavity. It occurs mostly in middleage men with alcohol-associated chronic pancreatitis and is seen in 3 to 7% of patients with pancreatitis. The diagnostic clue is an extremely elevated pleural fluid amylase level (> 1,000 IU/L). This must be differentiated from other causes of amylase-rich pleural effusion, including acute pancreatitis, malignance, and esophageal rupture (amylase level usually less than 1,000 IU/L). Multidetector row computed tomography has been considered a better noninvasive image study than endoscopic retrograde cholangiopancreatography or magnetic resonance cholangiopancreatography to detect the fistulous tract. Medical treatment and endoscopic stent placement for pancreatic duct obstruction are the first line therapies. However, surgical intervention is indicated when conservative therapy fails. Black pleural effusion is a rarely reported condition with etiologies including infection (Aspergillus niger and Rhizopus oryzae), metastatic melanoma, and hemorrhage. The black pleural effusion induced by a pancreaticopleural fistula was scarcely reported. In this case, the etiology of black pleural fluid may result from thoracic bleeding followed by hemolysis. When patients with a history of alcohol-associated pancreatitis presented with prolonged dyspnea and black pleural effusion, pancreaticopleural fistula should be considered.