ABSTRACT
SESSION TITLE: Critical Care in Chest Infections Case Report Posters 2 SESSION TYPE: Case Report Posters PRESENTED ON: 10/17/2022 12:15 pm - 01:15 pm INTRODUCTION: Shewanella are gram-negative bacteria that inhabit salt and brackish watery environments, rarely causing skin and soft tissue infections. We report a case of septic shock, bacteremia, and empyema due to Shewanella in a COVID-ARDS survivor who previously received ECMO. CASE PRESENTATION: A 67-year-old man with a medical history of hypertension, diabetes, recent COVID-ARDS illness complicated with STEMI, leading to a VT/VF arrest requiring 21-days of VV-ECMO support presented three weeks after discharge due to worsening oxygen needs. The patient was hypotensive, febrile, tachycardic, tachypneic, with SatO2 92% on HFNC> 50%FIO2. Labs showed leukocytosis, lactic acidosis, and acute kidney injury. Chest x-ray showed a loculated left pleural effusion. Broad spectrum antibiotics were started. Blood cultures grew Shewanella species in aerobic and anaerobic bottles. A CT of the chest is shown (Figure 1). Thoracentesis was performed with findings consistent with empyema (Table 1). The empyema was managed with pigtail catheters and TPAse-DNAse. Pleural fluid cultures had no growth. The patient improved and was discharged on 6-week course of IV ceftazidime. DISCUSSION: Shewanella is a rare cause of skin and soft tissue infections, following traumatic injuries in association with exposure to salt or brackish water. It has also been associated with pneumonia, in the setting of near drownings, in both fresh and saltwater. Individuals with underlying liver disease and immunocompromising conditions are at the highest risk of contracting the pathogen and manifesting illness. Shewanella algae and putrefaciens may manifest as deep ulcers with hemorrhagic bullae, bacteremia, endocarditis, and meningitis (1). In addition, biliary tract infections and peritonitis can occur (2). Our patient had no epidemiologic risk factors for Shewanella infection. Although nosocomial transmission is possible, we are not aware of any previous reports of such exposure in association with this infection. Given negative pleural fluid culture with positive blood culture, we hypothesize our patient's empyema is due to Shewanella given no other apparent infectious etiology. Studies have shown that approximately 40% of pleural infection are culture negative. It is possible that antibiotic therapy started before fluid collection lowered the diagnostic yield of thoracentesis. The prevalence of bloodstream infections during ECMO ranges from 3 to 18%, with coagulase-negative staphylococcus as the most frequent cause, followed by Candida spp., Pseudomonas aeruginosa, Enterobacteriaceae, Staphylococcus aureus and Enterococcus spp. (3) with no known reports of Shewanella per the ELSO registry. CONCLUSIONS: This case may confer possible healthcare-related acquirement of Shewanella. Our case adds awareness to clinicians about potential routes of inoculation, predisposing factors, and the wide clinical manifestations of Shewanellosis. Reference #1: Weiss TJ, Barranco-Trabi JJ, Brown A, Oommen TT, Mank V, Ryan C. Case Report: Shewanella Algae Pneumonia and Bacteremia in an Elderly Male Living at a Long-Term Care Facility. Am J Trop Med Hyg. 2021;106(1):60-61. Published 2021 Nov 15. doi:10.4269/ajtmh.21-0614 Reference #2: Savini V, Marrollo R, Nigro R, Fazii P. Chapter 6-Skin and Soft Tissue Infections Following Marine Injuries. In: The Microbiology of Skin, Soft Tissue, Bone and Joint Infections. Vol 2.;2017:93-103. Reference #3: S. Biffi et al. / International Journal of Antimicrobial Agents 50 (2017) 9–16 DISCLOSURES: No relevant relationships by Akram Alkrekshi No relevant relationships by Robert Kalayjian No relevant relationships by Ismini Kourouni No relevant relationships by Srinivasa Potla No relevant relationships by Zahra Zia