A PRIMARY EMPYEMA OF UNKNOWN DURATION DUE TO ANAEROBIC GRAM-NEGATIVE BACILLUS HAFNIA ALVEI

Abstract

TOPIC: Chest Infections TYPE: Medical Student/Resident Case Reports INTRODUCTION: Empyema is the presence of pus or bacteria in the pleural space. Incidence is increasing gradually with higher rates in the elderly with a greater prevalence in males [1]. Empyema is a fatal infection with a mortality rate of 20% [2]. Anaerobic Enterobacteriaceae accounting for less than 6% of empyema cases, are an infrequent cause [1]. CASE PRESENTATION: An 80-year-old male with a history of coronary disease, hypertension, hyperlipidemia, peripheral vascular disease, moderate aortic stenosis, a former smoker was seen at the pulmonary clinic for intermittent dyspnea with right-sided abdominal fullness of unknown duration and no symptoms of infection. He had significant asbestos exposure from his shipyard work. Around six months back, he underwent superior mesenteric artery (SMA) stenting for chronic abdominal angina. He was taking a super enzyme supplement to enhance his digestion. Chest x-ray review revealed right-sided effusion, which was also present before SMA stenting (Figure A1-2). A diagnostic thoracentesis showed brownish-green fluid with analysis indicative of empyema (Figure B). His blood work was normal. He was admitted, and a pigtail catheter was inserted into the right pleural space with purulent fluid drainage. He also underwent fibrinolysis. The pleural fluid culture grew Hafnia alvei sensitive to quinolones, aminoglycoside, and carbapenems (Amp C resistance pattern). At discharge, computed tomography and x-ray of the chest revealed empyema resolution, and the chest tube was removed (Figure C1-2). The initial antibiotic ertapenem was transitioned to levofloxacin for one month at discharge. At four weeks after discharge, his symptoms had entirely resolved DISCUSSION: H. alvei is a gram-negative facultative motile anaerobe of the Enterobacteriaceae family, a commensal in the gastrointestinal (GI) tract of humans and animals. It colonizes the oropharynx in humans [3]. It produces a cytolytic toxin, a virulent factor, causing acute gastroenteritis. It is a rare cause of nosocomial and community-acquired infection with a preference for biliary tree infection and has lower mortality [4-5]. In patients with multiple comorbidities and immunosuppressed, it causes extraintestinal diseases such as endophthalmitis, bronchopneumonia, gastroenteritis, and meningitis [5]. The infection source is the GI tract via gut translocation or oropharynx venous drainage draining into the heart and forced into the visceral pleura or alveolar capillary bed [5-6]. In our patient, another source could be the contaminated supplement (it contains Ox bile) CONCLUSIONS: In primary empyema of remote duration and an infrequent cause, a possible source could be the GI tract or the oropharynx. Clinicians should be aware of supplement contents that could be a source of infection REFERENCE #1: Godfrey MS, Bramley KT, Detterbeck F. Medical and Surgical Management of Empyema. Semin Respir Crit Care Med. 2019;40(3):361-74 REFERENCE #2: Corcoran JP, Wrightson JM, Belcher E, DeCamp MM, Feller-Kopman D, Rahman NM. Pleural infection: past, present, and future directions. Lancet Respir Med. 2015;3(7):563-77 REFERENCE #3: Fazal BA, Justman JE, Turett GS, Telzak EE. Community-acquired Hafnia alvei infection. Clin Infect Dis. 1997;24(3):527-8 DISCLOSURES: No relevant relationships by Phillip Beck, source=Web Response no disclosure on file for Wilson Grace; No relevant relationships by Ethan Karle, source=Web Response No relevant relationships by AARON MILLER, source=Web Response No relevant relationships by Shakuntala Patil, source=Web Response No relevant relationships by SACHIN PATIL, source=Web Response No relevant relationships by ANTONY RAWINDRARAJ, source=Web Response