THE SUPERINFECTION THAT’S A REAL HEADACHE

Abstract

SESSION TITLE: Critical Care 1 SESSION TYPE: Fellow Case Report Posters PRESENTED ON: 10/09/2018 01:15 PM - 02:15 PM INTRODUCTION: Legionnaires’ disease serves as one of the most ubiquitous causes of community-acquired pneumonia. We are reporting a rare case of influenza with a superinfection of Legionnaires disease presenting with altered mental status due to severe hyponatremia. CASE PRESENTATION: A 60-year-old woman with no significant medical history was brought to the ER by her sister after she was found on the ground. According to her sister, the patient had a right facial droop with dried blood in her nares and sub-conjunctival hemorrhage as well as an “unusual posturing” of her hands and feet. Prior to the event, she had been complaining of nausea and vomiting for the past two days for which she had been taking Alka-Seltzer and herbal teas. On physical examination, she remained unconscious with bilateral conjunctival swelling and injection but no nuchal rigidity or apparent head injury. Temperature was 99.7 F with heart rate of 70 bpm, blood pressure was elevated to 221/105 mmHg. She was intubated with subsequent improvement in BP. The initial laboratory results revealed hyponatremia with sodium of 109 mEq/L and elevated creatinine kinase level of 11108. Urine toxicology report was negative. CT imaging of head demonstrated cerebral edema with loss of the gray and white matter significant for global ischemia. After admission to the ICU for management of hyponatremia and cerebral edema, she was found to be influenza and legionella positive. She completed a course of Tamiflu and Levaquin and sodium was slowly corrected to 134mEq/L. She was extubated on hospital day 3, by day 6 she had complete restoration of mental status and strength and was discharged home. DISCUSSION: While the most common superinfections with influenza are S. pneumoniae, H. influenzae, and S. aureus, Legionella has been associated with influenza virus (1). There exists no particular set of clinical features that should raise suspicion for the disease as the presentations may differ. Legionella etiology of community acquired pneumonia serves as a strong predictor for low sodium level, independent of disease severity (2). Although previous studies suggested antidiuretic hormone-independent mechanisms such as direct renal effects of cytokines and toxins as the culprit, the mechanism still remains unknown. (3). However, since hyponatremia can cause a number of serious complications, such as coma and death, there still needs to be a careful management of those patients presenting as symptomatic hyponatremia. When dealt with the right management with correction of sodium level and appropriate antibiotics in a timely manner, one may expect a dramatic improvement in patients’ physical and mental status. CONCLUSIONS: Even though the extent of hyponatremia in patients with Legionella pneumonia may not correlate with the severity of the disease, hyponatremia in itself can lead to dangerous outcomes and suspicion for legionella infection should be high. Reference #1: Morris DE, Cleary DW, Clarke SC. Secondary Bacterial Infections Associated with Influenza Pandemics. Frontiers in Microbiology. 2017;8:1041. https://doi.org/10.3389/fmicb.2017.01041. Reference #2: Yu, Victor L. Legionnaires' Disease: Importance of High Index of Suspicion in Patients in the ICU with Community-Acquired Pneumonia. CHEST. 2014;145:2. DOI: https://doi.org/10.1378/chest.13-2170 Reference #3: Schuetz P, Haubitz S, Christ-Crain M, Albrich WC, Zimmerli W, Mueller B. Hyponatremia and anti-diuretic hormone in Legionnaires’ disease. BMC Infectious Diseases. 2013;13:585. https://doi.org/10.1186/1471-2334-13-585. DISCLOSURES: No relevant relationships by Erica Altschul, source=Web Response No relevant relationships by Cyra-Yoonsun Kang, source=Web Response