View Abstract

A5677 - Influenza B Causing Severe ARDS
Author Block: M. P. Clark-Coller1, S. Alqalyoobi2, M. Schivo2, M. Omer3; 1Internal Medicnie, University of California Davis Medical Center, Sacramento, CA, United States, 2Division of Pulmonary and Critical Care, University of California Davis Medical Center, Sacramento, CA, United States, 3Department of Cardiology, University of Missouri, Kansas City, Olathe, KS, United States.
Introduction: Acute respiratory distress syndrome (ARDS) due to influenza A is well described. Influenza B is considered a less severe infection with lower mortality. Our case describes severe ARDS due to influenza B complicated by bacterial pneumonia.
Case description: A 17-year-old previously healthy female presented to a community hospital with four days of cough, fever, myalgias, and nasal congestion, and two days of facial swelling and dyspnea. She tested positive for influenza B two days prior. She was emergently intubated for hypercapnic respiratory failure and was treated with broad spectrum antibiotics. She was transferred to our center for evaluation of extracorporeal life support (ECLS) for respiratory failure from ARDS. On arrival, she was febrile to 41C, required vasoactive pressors due to septic shock, inhaled nitric oxide, and ventilator support. She was found to have bilateral patchy infiltrates on chest radiograph, a left-sided opacification of the left lung, and subcutaneous emphysema. She had bilateral chest tubes placed and was started on veno-venous ECLS for refractory mixed hypoxic/hypercapnic respiratory failure due to influenza B with bacterial super-infection. Blood and respiratory cultures grew methicillin susceptible staphylococcus aureus; respiratory viral panel confirmed influenza B. Her course was complicated by Pseudomonas, Aggregatibacter segnis, and Candida glabrata pneumonia, bilateral empyemas, and Prevotella melaninogica bacteremia. She underwent multiple bronchoscopies for removal of obstructive red blood cell casts. A Computed Tomography (CT) scan of the chest on her 40th day of hospitalization showed bilateral necrotizing pneumonia and bronchiectatic changes with severely reduced aeration. On hospital day 45 she was evaluated for lung transplant. However, due to her limited prognosis based on prolonged ECLS and multiorgan failure, she was denied. She remained on ECLS for 46 days. On hospital day 46, care was compassionately withdrawn and she subsequently died.
Discussion: This case illustrates the potential severity of influenza B infection. Generally considered less threatening than influenza A, influenza B has been shown to cause severe disease even in immunocompetent hosts.i Influenza B can cause combined viral pneumonia and predispose to a post-viral bacterial pneumonia. This case raises the question of whether post-influenza fungal pneumonia exists as an independent entity warranting further study, and whether viral-induced changes to the host affect the course of fungal infection.