PULMONARY CAVITARY LESION WITH RARE PSEUDOMONAS STUTZERI

Abstract

SESSION TITLE: Monday Medical Student/Resident Case Report Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/21/2019 02:30 PM - 03:15 PM INTRODUCTION: Pseudomonas stutzeri is a gram-negative rod bacterium infrequently associated with clinical infection. We present a case of pulmonary cavitary lesions caused by P.stutzeri. CASE PRESENTATION: A 59-year-old male with history significant for intravenous (IV) heroin abuse (last use 1 week prior), splenectomy and culture negative endocarditis (10 months prior) presented to the hospital with 1 week of chest pain, dyspnea and subjective fevers. Within a few hours of admission, a rapid response was called for altered mental status, chest pain and tachypnea. Computed tomography of the chest revealed a 12cm cavitary left lower lung lesion. He was placed on tuberculosis precautions and subsequently transferred to the Intensive Care Unit (ICU) for further management. Blood cultures were obtained prior to empiric vancomycin plus piperacillin/tazobactam. He required intubation for impending respiratory failure. Bronchoscopy with bronchoalveolar lavage (BAL) was performed demonstrating copious mucus and purulent secretions bilaterally. Approximately 36 hours into his admission, he suffered a PEA (pulseless electrical activity) arrest. Return of spontaneous circulation (ROSC) was achieved after 15 minutes of cardiopulmonary resuscitation (CPR). Physical exam revealed diffuse crepitus, subcutaneous emphysema tracking along posterior thorax extending into left lateral thigh and profound scrotal swelling. Arterial blood gas demonstrated acidemia with hypercarbia. Within less than an hour, he suffered a second PEA arrest. There was concern for ruptured pleural cavitary lesion leading to a tension pneumothorax. Needle decompression performed bilaterally was unsuccessful; surgery at bedside placed left hemithorax chest tube. Again, achieved ROSC after 18 minutes of CPR. Unfortunately, within a few minutes he decompensated into ventricular fibrillation. Further resuscitation efforts a third time were unsuccessful. Post-mortem blood cultures were negative but his BAL cultures were positive for pan-sensitive Pseudomonas stutzeri. All acid-fast bacilli smears and cultures were negative. DISCUSSION: Pseudomonas stutzeri has rarely been reported as a cause of necrotizing pneumonia (1) and may represent only 1% of all clinical Pseudomonas isolates (2). In our patient, the timeline of events, whether the cavitary lesion ruptured from the positive pressure of mechanical ventilation or as a consequence of CPR remains a mystery. CONCLUSIONS: There is debate in the literature regarding the pathogenicity of this organism which is frequently deemed to be colonization rather than pathogenic. However, in the case of this patient, all other infectious work up was negative and no alternative pathogen could be linked to the development of the cavitary lesions. This case emphasizes the necessity of diagnostic testing to identify uncommon pathogens. Reference #1: Lin KH et al, Pseudomonas stutzeri necrotizing pneumonia in pre-existing pulmonary tuberculosis. Intern Med. 2014;53(21):2543-6. 2014 Nov 1. Reference #2: Bisharat, N et al, 10-Years Hospital Experience in Pseudomonas stutzeri and Literature Review. The Open Infectious Diseases Journal, 2012, 6, 21-24. DOI: 10.2174/1874279301206010021 DISCLOSURES: No relevant relationships by Zachary Bugos, source=Web Response No relevant relationships by Brandon Smith, source=Web Response