RARE CASE OF NOCARDIA EMPYEMA IN AN IMMUNOCOMPROMISED HOST

Abstract

SESSION TITLE: Wednesday Medical Student/Resident Case Report Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/23/2019 09:45 AM - 10:45 AM INTRODUCTION: Nocardia is an aerobic weakly staining gram positive organism found commonly in the soil and decaying matter. It commonly affects the respiratory tract causing pneumonia in immunocompromised individuals but can lead to empyema and abscess formation. Extra-pulmonary disease occurs in 50% of patients presenting with pulmonary disease; with the brain being the most frequently affected. Standard treatment consists of a sulfonamide and a second agent such a carbapenem for strains that may be resistant. CASE PRESENTATION: A 66-year-old male with a past medical history significant for esophageal cancer, chronic lymphocytic leukemia, nicotine abuse, and diabetes mellitus presented to the emergency department complaining of increased dyspnea, weight loss, and shortness of breath associated with copious green expectorations. A chest x-ray showed wedge shaped opacity laterally in the right upper lobe as well as pleural effusion in the right lower lobe. Subsequent CTA confirmed a right apical cavitary mass, a right lower lobe consolidation suggesting atelectasis, and bilateral infiltrates consistent with multilobar pneumonia. Empiric antibiotic therapy consisting of vancomycin and piperacillin-tazobactam was promptly initiated pending results of sputum and blood cultures. Thoracentesis fluid analysis revealed an exudative pattern showing a RBC count of 481,000; WBC count 76,800 with 93% neutrophils; glucose 2; LDH 8180. Pleural fluid grew Nocardia paucivarans via Maldi-Toff spectometry. CT head ruled out brain involvement. Antibiotics were changed to Trimethroprim/ Sulfamethoxazole and Imipenem. Therapy with TPA/ dornase was initiated for enzymatic empyema degradation. DISCUSSION: Nocardia is an uncommon bacterial infection with the ability to cause suppurative disease in humans and animals. Nocardia paucivorans is a recently described species with only 33 cases reported over a 20-year span. It is often an opportunistic infection affecting those who are immunocompromised with risk factors such as malignancy, glucocorticoid therapy, those receiving cytotoxic chemotherapy, and HIV infection. This patient was certainly at risk due to his history of esophageal cancer and CLL. Prior to his infection, he received eight cycles of Rituximab and Bendamustine increasing his risk of impaired humoral and cellular mediated immunity. Literature review shows since 2000, when this bacterium was first identified, there are only three previous cases of N. paucivorans empyema in patients. CONCLUSIONS: In patients with various immunocompromising conditions, Nocardia should be included in the differential diagnosis as a potential cause of pulmonary infiltrate. Imaging may be variable as pulmonary Nocardial involvement may include nodules, cavities, interstitial infiltration, pleural effusions, and empyema. This case report illustrates rapid recognition leading to appropriate therapy and improved clinical outcome. Reference #1: Jacopo Monticelli, Roberto Luzzati, Cristina Maurel, Chiara Rosin, Romina Valentinotti, Claudio Farina Mediterr J Hematol Infect Dis. 2015; 7(1): e2015011. Published online 2015 Jan 1. https://doi.org/10.4084/MJHID.2015.011 Reference #2: Martínez, R., Reyes, S., & Menéndez, R. (2008). Pulmonary nocardiosis: Risk factors, clinical features, diagnosis and prognosis. Current Opinion in Pulmonary Medicine, 14(3), 219-227. https://doi.org/10.1097/mcp.0b013e3282f85dd3 Reference #3: Overview of Nocardiosis - Generalized Conditions. (n.d.). Retrieved from https://www.merckvetmanual.com/generalized-conditions/nocardiosis/overview-of-nocardiosis DISCLOSURES: No relevant relationships by Kevin Dawkins, source=Web Response No relevant relationships by Justin George, source=Web Response No relevant relationships by roberto mercado, source=Web Response No relevant relationships by Niraj Patel, source=Web Response No relevant relationships by Belissa Ramos-Chaves, source=Web Response No relevant relationships by Wilhelmine Wiese-Rometsch, source=Web Response