Características radiográficas de la neumonía adquirida en la comunidad en el adulto inmunocompetente hospitalizado según el agente causal

Abstract

In a clinical setting the chest radiograph is the reference standard in establishing the diagnosis of community-acquired pneumonia (CAP). Objectives: This study aimed to assess interobserver reliability (IR) of radiographic findings and the relationship to different respiratory pathogens in CAP. Methods: Chest radiographs of 300 immunocompetent adult patients hospitalized with pneumonia, obtained from a database, were reviewed by three residents of radiology without specific clinical information. Main pattern of pulmonary infiltrates, topographic localization, extent of pneumonia, presence of pleural fluid, thickened bronchial walls, lymphadenopathy and air bronchogram were scored. Sputum and blood cultures, serological tests and nasopharyngeal swab for respiratory virus detection by molecular diag- nostic techniques were performed to identify the causative pathogen. Results: Clinical manifestations and chest X-ray findings were similar in pneumonias caused by different respiratory pathogens: classic bacteria, respiratory viruses and atypical microorganisms. The alveolar pattern of lobar distribution predominated in bacterial pneumonia; meanwhile, interstitial or mixed alveolar-interstitial pattern with ground glass opacities predominated in viral and atypical pneumonias. IR was fair to good (kappa > 0.6) for determining the main pattern of infiltrates, anatomical location and the presence of pleural effusion, their anatomical location and extension. IR was moderate (kappa 0.4-0.6) for determining the extent of pneumonia and signs of congestive heart failure. Conclusion: Simple features such as main pattern description, anatomical location, identifying the involved lobes and pleural fluid recognition showed fair to excellent interobserver reliability. Chest radiographs was of limited value in predicting the causative pathogen but were of beneficial use to characterize pulmonary infiltrates and to detect complications such as parapneumonic effusion.