The role of transthoracic ultrasonography in predicting the outcome of community-acquired pneumonia in hospitalized children

RESEARCH ARTICLE The role of transthoracic ultrasonography in predicting the outcome of communityacquired pneumonia in hospitalized children I-Chen Chen1, Ming-Yen Lin2,3, Yi-Ching Liu1, Hsiao-Chi Cheng1, Jiunn-Ren Wu1,4, JongHau Hsu1,4*, Zen-Kong Dai1,4* a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 1 Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan, 2 Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan, 3 Faculty of Renal Care, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan, 4 Department of Pediatrics, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan * (JHH); (ZKD). Abstract OPEN ACCESS Citation: Chen I-C, Lin M-Y, Liu Y-C, Cheng H-C, Wu J-R, Hsu J-H, et al. (2017) The role of transthoracic ultrasonography in predicting the outcome of community-acquired pneumonia in hospitalized children. PLoS ONE 12(3): e0173343. https://doi.org/10.1371/journal.pone.0173343 Editor: Wei-Chun Chin, University of California, Merced, UNITED STATES Received: April 17, 2016 Accepted: February 20, 2017 Published: March 16, 2017 Copyright: © 2017 Chen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the paper. Funding: This research was supported by the grant from the Kaohsiung Medical University Hospital, Taiwan (KMUH103-3M30) and Ministry of Science and Technology, R.O.C. (MOST105-2314-B-037011- and MOST 103-2314-B-037-023-MY3). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Transthoracic ultrasound (TUS) has recently become a valuable tool in the diagnosis of community-acquired pneumonia (CAP). This study assessed the association between TUS findings and clinical outcome in children with CAP. The medical records of pediatric patients hospitalized with CAP who underwent transthoracic ultrasonography within 48 hours of admission were retrospectively reviewed. Associations between the TUS findings and patient outcome were analyzed, including intensive care unit (ICU) admission, length of hospital stay, and tube thoracotomy. The study enrolled 142 patients (median age, 60 months): 28 (19.7%) required ICU admission, 14 (9.89%) underwent tube thoracotomy, and 26 (18.3%) had a hospital stay > 9 days. Multifocal involvement seen by TUS were independently associated with ICU admission, a prolonged hospital stay, and tube thoracotomy (p = 0.0027, p = 0.02, and p = 0.0262, respectively). A pleural effusion and fluid bronchogram were independent predictors of a longer hospital stay (p = 0.003 and p = 0.006, respectively). In addition, a fluid bronchogram was an independent predictor of tube thoracotomy (p = 0.0262). Conclusion TUS findings of fluid bronchogram, multifocal involvement, and pleural effusion were associated with adverse outcomes, including longer hospital stay, ICU admission, and tube thoracotomy in hospitalized CAP children. Therefore, TUS is a novel tool for prognostic stratifications of CAP in hospitalized children. Introduction Community-acquired pneumonia (CAP) is one of the most common infectious diseases and an important cause of morbidity and mortality in children [1, 2]. Although chest radiography is currently the most commonly used tool for the detection of CAP, it is not absolutely PLOS ONE | https://doi.org/10.1371/journal.pone.0173343 March 16, 2017 1 / 11 Transthoracic ultrasonography in community-acquired pneumonia in children Competing interests: The authors have declared that no competing interests exist. Abbreviations: BTS, British Thoracic Society; CAP, community-acquired pneumonia; TUS, Transthoracic ultrasound. necessary for the diagnosis in children and it involves radiation exposure [3–5]. Transthoracic ultrasound (TUS) is an emerging imaging modality in the assessment of pneumonia [6, 7]. TUS offers the advantages of more specific findings, such as an air bronchogram, fluid bronchogram, B-lines, or minimal effusion, which are often difficult to detect or differentiate by routine chest radiography. An air bronchogram reflects residual air within the consolidation, while a fluid bronchogram indicates fluid-filled airways [8]. B-lines are generated when the TUS beam is intercepted by excessive air, a liquid film, an exudate, or fibrosis in the pleural space [9]. Recent studies suggested that TUS is a feasible tool in the diagnosis and follow-up of pediatric pneumonia with the advantage of no radiation exposure [6–8, 10, 11]. However, whether TUS has a role in the prognostic stratification has not been investigated in hospitalized children with CAP. Predicting clinical outcome of CAP can be beneficial in the management of pediatric CAP. However, to date there is no standard imaging modality for predicting the outcome of CAP. Recent studies have shown that radiographic findings are associated with the severity of CAP in children [5, 12, 13]. For example, multilobar involvement on the admission chest radiograph was related to complicated pneumonia [13, 14]. Nevertheless, the prognostic role of radiography in pediatric CAP has not been established. We postulated that TUS may have a role in predicting the clinical outcome of pediatric CAP because TUS can detect more specific and additional findings than the opacities seen on chest radiographs [8, 10, 15, 16]. Therefore, this study assessed whether TUS is valuable for predicting the outcome of CAP in hospitalized children. Methods We conducted a retrospective cohort study at Kaohsiung Medical University Hospital (Kaohsiung, Taiwan). Our local Institutional Review Board approved the study (KMUHIRB20120062). All patient records and clinical information were analyzed anonymously. Patients We retrospectively analyzed the electric medical records of patients between 6 months and 18 years of age seen between January 1, 2010, and December 31, 2012. The inclusion criteria were children admitted to our hospital with a diagnosis of CAP and who underwent TUS within 48 hours of admission. We used International Classification of Diseases (ICD-9-CM) diagnosis codes (481, 482.x, 483.x, 485, and 486) to detect hospitalized CAP cases and the National Health Insurance billing code for TUS to identify patients for our study. (Fig 1) We excluded those who had underlying diseases, including respiratory tract anomalies, immunodeficiency, cerebral palsy, neuromuscular diseases, congenital heart disease, and malignancy. Clinical examinations were done and recorded using a digital system by a physician within 24 hours of admission. The data were extracted from our digital system of medical charts and imag (...truncated)