A rare case spontaneous bacterial empyema due to pasteurella multocida

SESSION TITLE: Disorders of the Pleura 2 SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/09/2018 01:15 pm - 02:15 pm INTRODUCTION: Spontaneous Bacterial Empyema (SBEM) is an uncommon complication in patients with hepatic hydrothorax. This occurs in approximately 13-16% of cases, with a mortality rate of 20%. Pathogenesis is similar to that of spontaneous bacterial peritonitis (SBP) in that transient bacteremia and bacterial translocation leads to the infection. In upto 40% of the cases, SBEM can occur even in the absence of SBP or even ascites. Most common causative organisms are Escherichia coli, Klebsiella, and Enterococcus. Here we present a rare case of Pasteurella multocida (P. multocida) causing SBEM without known animal contact. CASE PRESENTATION: A 65-year-old female with a history of decompensated Hepatitis C cirrhosis, recurrent hepatic hydrothorax, and hepatocellular carcinoma status post chemoablation presented with a one-week history of cough and dyspnea. The patient was hypoxic on oximetry. The clinical and laboratory evaluation was unremarkable for an infectious etiology. There were no concomitant ascites. Chest radiology and bedside ultrasound showed right-sided pleural effusion. Diagnostic and therapeutic thoracentesis yielded 1L of amber-colored fluid. Fluid studies showed pH 7.45, LDH 353 (sLDH 307), protein 3.4 (serum 8.1), albumin 1.6 (serum 2.8), 77,170 nucleated cells with 83% neutrophils. Cytology was negative for malignant cells. Fluid culture returned positive for P. multocida. She was treated with intravenous ceftriaxone 1g daily. Albumin was not administered. DISCUSSION: Although P. multocida empyema has been described as a rare entity, to our knowledge, this is the first case of P. multocida SBEM. It is a gram-negative, non-motile, facultative anaerobic coccobacilli, found mostly in the oral flora of cats (70%), dogs and other mammals. Commonly presenting as a skin infection, the lungs are a rare site of colonization by this organism, although it can be transmitted by contaminated aerosols or inoculation with animal secretions. Chronic pulmonary diseases and immunosuppressive states such as malignancy, diabetes, and cirrhosis are important predisposing factors. This likely led to our patient acquiring this infection without an overt zoonotic contact. CONCLUSIONS: SBEM is an underdiagnosed complication of recurrent hydrothorax as most patients do not undergo diagnostic thoracentesis. Diagnostic criteria for SBEM is similar to that of SBP; >250 PMNs and positive culture, SAAG >1.1, which our case met. Our patient’s LDH was elevated likely due to a large number of leukocytes in the fluid. There are important distinctions between SBEM and pneumonia associated empyema (PAE), as the management differs drastically. In PAE, chest tube and antibiotics remain the mainstay of therapy. Whereas, antibiotics and albumin are sufficient in treatment of SBEM. There is a relative contraindication to chest tube placement in patients with recurrent hydrothorax as this can lead to rapid volume depletion. Reference #1: Lam, S., Johnson, M., et.al. (2014). Spontaneous Bacterial Empyema: Not Your Average Empyema. Retrieved March 03, 2018, from https://doi.org/10.1016/j.amjmed.2014.01.034 Reference #2: Boyer TD, Kahn AM, Reynolds TB. Diagnostic Value of Ascitic Fluid Lactic Dehydrogenase, Protein, and WBC Levels. Arch Intern Med. 1978;138(7):1103–1105. https://doi.org/10.1001/archinte.1978.03630320041014 Reference #3: Jogani, S., Subedi, R., et.al. (2016). Pasteurella multocida pleural effusion: A case report and review of literature. Retrieved March 03, 2018, from https://doi.org/10.1016/j.rmcr.2016.07.013 DISCLOSURES: No relevant relationships by Ayushi Chauhan, source=Web Response No relevant relationships by Denise Marie Francisco, source=Web Response No relevant relationships by David Fraulino, source=Web Response No relevant relationships by Parin Shah, source=Web Response No relevant relationships by Aniket Sharma, source=Web Response