Comparison of diagnostic performances between bedside sonography and chest x-ray in severe pneumonia

Objective To evaluate the diagnostic performances of bedside lung ultrasound (US) and chest radiography (CXR) in patients with severe pneumonia.Method Lung ultrasound (US),CXR and chest CT were performed in sequence in adult patients admitted to the emergency department for suspected acute respiratory failure caused by severe pneumonia.Here,chest CT served as a" golded standard" for comparison.The diagnostic efficacy of US for the detection of severe pneumonia,defined as rapidity and accuracy (sensitivity,specificity,positive predictive value,negative predictive value) were compared with CXR.Results The number of patients with consolidation of lung,pleural alteration,subpleural pathological changes,and pleural effusion in the severe pneumonia group was higher than that in the nonpneumonia group.Sensitivity of bedside ultrasound examination for the diagnosis of severe pneumonia was 95.7％,and specificity 96.3％,positive predictive value 95.7％,negative predictive value 96.3％,and accuracy 96.0％.There were differences in sensitivity,negative predictive value and accuracy found between CXR and US.Conclusions Bedside chest ultrasound is a reliable device for the diagnosis of severe pneumonia,and superior to CXR in this setting,allowing a more prompt diagnosis and treatment. Key words: Ultrasonic inspection;  Chest X-ray;  Severe pneumonia