(1194) Atypical Case of Chronic Empyema and Calcified Pleura Secondary to Pasteurella multocida

Introduction: Pasteurella multocida is a zoonotic bacteria associated with soft tissue infections from animal scratches/bites. We present a case of empyema secondary to P. multocida with extensive calcifications.

Description: Patient is a 64 year old male with a history of tobacco use and COPD who presented with 4 months of dyspnea and productive cough. Initial vitals showed tachycardia, tachypnea, and hypoxia. Exam was notable for respiratory distress with right basilar crackles. Laboratory values noted leukocytosis and respiratory acidosis with compensatory metabolic alkalosis. CT chest with contrast revealed biconvex gas and fluid collection on both sides of calcified pleura in the right lung base, concerning for empyema and lung abscess. Patient was started on empiric ceftriaxone/doxycycline and steroids. Pulmonology and CT surgery (CTS) were consulted; thoracoscopy was deferred due to concerns for significant blood loss and lung injury. Instead, a chest tube was placed which drained thick milky fluid. However, he subsequently developed worsening respiratory failure, needing intubation. Pleural fluid cultures showed P. Multocida. Antibiotics were switched to unasyn. His respiratory status improved and he was extubated. On day 13, his chest tube was removed. On day 18, he developed leukocytosis and worsening dyspnea. Repeat CT showed recurrent right pleural effusion and a chest tube was reinserted. A 2nd CTS consultation was requested, but antibiotic therapy and chest tube drainage were recommended. New pleural fluid studies grew MRSA and Vancomycin was started. His chest tube continued to drain and a 3rd CTS consultation was requested. CTS then performed a right VATS minithoracotomy, complete pleural decortication, and resection of the calcified mass. His symptoms improved and he was discharged on day 54 with 10 more days of oral antibiotics.

Discussion: P. Multocida is an uncommon pathogen implicated in pleural disease, with severe presentations and a high mortality rate, especially in individuals with chronic pulmonary disease. It is likely that this patient’s colonization of P. Multocida and impaired mucosal clearance from COPD contributed to the development of empyema. It is important to consider screening for animal exposure in cases of empyema that do not respond to initial empiric therapy.