Case Presentation: A 61-year-old African American male with a history of alcohol use disorder and chronic pancreatitis presented to the hospital with shortness of breath and severe chest pain that worsened with inspiration. Two months prior to admission he was found to have a 17x12x12 cm pancreatic pseudocyst and subsequently underwent cystogastrostomy with stent placement for treatment. The patient had absent breath sounds over the left lung field on exam, along with egophony and dullness to percussion. Vitals signs were notable for a pulse of 121, temperature of 101 F, and oxygen saturation of 90% on room air. Chest CT revealed a large, loculated, left-sided pleural effusion with lung collapse and mediastinal shift. Emergent thoracentesis was performed resulting in 2 L of purulent fluid drained. Initial pleural fluid analysis was significant for an LDH of 3,800 U/L and 47,000 nucleated cells. Empyema was suspected, and the patient began antibiotic therapy with piperacillin/tazobactam and vancomycin. Symptoms improved initially, but rapidly worsened in a matter of days. Repeat CT was obtained and showed a re-accumulation of pleural fluid. 3 L of fluid was then drained following chest tube placement. Further pleural fluid analysis was performed and significant for a lipase of over 3,000 U/L and an amylase of 6,560 U/L, concerning for a pseudocyst leak or pancreatic fistula. MRCP was unremarkable. A diagnostic ERCP was subsequently performed, which revealed a small pancreaticopleural fistula between a pseudocyst and the left thorax. The patient was made NPO and started on TPN and octreotide for management. He then underwent repeat ERCP with stent placement for treatment and was discharged the following day.
Discussion: Pancreaticopleural fistula is a rare, potentially life-threatening cause of pleural effusion. It is most commonly diagnosed in men between the age of 40-50 with a history of alcoholism (1, 2). 3-7% of patients with pancreatitis are diagnosed with a pancreaticopleural fistula, which most often arises from pseudocysts (2). Clinical manifestations include shortness of breath, chest pain that worsens with inspiration, and unilateral reduced or absent breath sounds on exam. Massive loculated pleural effusions, particularly left-sided effusions, are often seen on imaging (3). Pleural fluid analysis is imperative for diagnosis. High lipase and amylase, often in excess of 1,000 U/L, allows for differentiation of pancreaticopleural fistulas from empyema and other etiologies of exudative pleural effusions (2). CT, MRCP, and ERCP are the preferred imaging modalities to visualize and assess the site/size of pancreaticopleural fistulas (3, 4). However, unremarkable MRCP, as evident by the findings in our patient, does not necessarily exclude diagnosis (3). If clinical suspicion remains high for a pancreatic fistula, further evaluation with ERCP may be warranted (6). Management with an NPO diet, TPN, octreotide, antibiotics, chest tube placement, and ERCP with stenting has proven effective in eliminating pancreaticopleural fistulas (5, 6). Additionally, surgical intervention should be considered in refractory cases (3, 5, 6).
Conclusions: Pancreaticopleural fistulas are a rare cause of pleural effusions that should be included in the differential diagnosis for patients presenting with shortness of breath, chest pain, and a history of pancreatitis.