SESSION TITLE: Chest Infections 3 SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/09/2018 01:15 PM - 02:15 PM INTRODUCTION: Bordetella bronchiseptica species are documented as commensals and a respiratory pathogen in a number of mammals,pertinently causing tracheobronchitis in dogs(i.e canine cough), atrophic rhinitis in pigs,and snuffles in rabbits.Since 1911,cases of B. bronchiseptica have been reported to cause respiratory infection in humans with underlying immunosuppression. Here we report a case of B.bronchiseptica pneumonia successfully treated with piperacillin-tazobactam & azithromycin. CASE PRESENTATION: A 24-year-old male was admitted to the ICU with a week history of fever,dry cough,post-tussive emesis, and hypotension with concern for sepsis.The patient had a history of perinatal HIV,CD4+ count on admission was <10 and the viral load was 109,295 cop/ml.He had been admitted with similar complaints twice in the past two months, primarily for chronic cough and fever.His vitals on admission were a fever of 38°C, BP 84/62 mmHg and HR 123.He had coarse breath sounds bilaterally, with crackles in the left lower chest.Chest imaging showed a cystic/cavitary lesion was noted measuring 5 x 2 cm in axial dimensions within the left lower lobe with an air-fluid level,and multiple small cystic lesions with a background of mild diffuse ground-glass opacity observed.Sputum culture and bronchoalveolar lavage fluid culture grew gram-negative coccobacillus that was identified as B.bronchiseptica. DISCUSSION: B. bronchiseptica naturally infects non-human mammals, unlike B.pertussis which is an obligate human pathogen.Reports of human B. bronchiseptica infections are limited to case reports or case report series; infection in humans usually requires immunosuppression or malignancy.The infection presents as a lobar pneumonia but often includes chronic cough > 1 month. The incubation period ranges from 1 - 8 days, and the infection can be transmitted from infected animals or humans through respiratory droplets.It has the potential to cause recurrent infection due to its ability to survive intracellularly and evade killing by macrophages due to acid tolerance.It expresses protein adhesions called filamentous hemagglutinin and pretactin that allows it to invade the respiratory epithelium where it can survive and resist antibody and compliment mediated phagocytosis,it does not produce the pertussis toxin,but causes local damage by adenylate cyclase hemolysin and dermonecrotic toxins. These factors allow it to persist for long durations and cause cavitary pneumonias. CONCLUSIONS: B. bronchiseptica is an animal pathogen and there are no guidelines on the management of human infection.Pulse-field get electrophoresis analysis by Celia et al. showed that it shows resistance for aminopenicillins, cephalosporins and aztreonam; but generally susceptible to macrolides and quinolones with total duration of antibiotic therapy 2 - 4 weeks and consideration for longer duration therapy in severely immunocompromised and neutropenic patients. Reference #1: García-de-la-Fuente C, Guzmán L, Cano ME, et al. Microbiological and clinical aspects of respiratory infections associated with Bordetella bronchiseptica. Diagnostic Microbiology and Infectious Disease. 2015;82(1):20-25. https://doi.org/10.1016/j.diagmicrobio.2015.01.011. Reference #2: Gueirard P, Weber C, Le Coustumier A, Guiso N. Human Bordetella bronchiseptica infection related to contact with infected animals: persistence of bacteria in host. J Clin Microbiol. 1995;33(8):2002-2006. Reference #3: Schneider B, Gross R, Haas A. Phagosome Acidification Has Opposite Effects on Intracellular Survival of Bordetella pertussis andB. bronchiseptica. Infect Immun. 2000;68(12):7039-7048. https://doi.org/10.1128/IAI.68.12.7039-7048.2000. DISCLOSURES: No relevant relationships by Janaki Deepak, source=Web Response No relevant relationships by Muhammad Sameed, source=Web Response No relevant relationships by Scott Sullivan, source=Web Response
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