Comparison of the diagnostic value of ultrasound with chest CT scan in patients with unspecified pulmonary pneumonia in the emergency department

Objective: according to the most recent guidelines, the recommended imaging approaches for the diagnosis of pneumonia are chest x-ray (cxr) and computed tomography (ct) scan. however, there are limitations to these approaches. lung ultrasound (lus) has attracted a lot of attention in intensive care units (icus) and emergency departments. considering the importance of the timely diagnosis and proper treatment of pneumonia, this study aimed to determine the diagnostic value of bedside lus in comparison to chest ct scans in patients with suspected pneumonia or unspecified cxr findings in the emergency department. methods: this prospective descriptive-analytic study was conducted in the emergency department of imam reza hospital. patients aged 3 years and older with early diagnosis of pneumonia or any unspecified cxr findings with an indication of ct scan were included in the study. lus was performed with a deep curved and linear surface probe. the results obtained from the chest ultrasound were compared with the results obtained by ct scan as the diagnostic gold standard. results: a total of 175 patients were included in this study. according to the results, the sensitivity and specificity of lus in the diagnosis of subpleural consolidation were 94.1% and 100%, respectively, and the positive predictive value and the negative predictive value were 100% and 33.3%, respectively. the sensitivity and specificity of lus in diagnosing pleural effusion were 69.2% and 100%, respectively, and the positive predictive value and the negative predictive value were 100% and 90.7%, respectively. furthermore, the sensitivity of lus in diagnosing dynamic air bronchogram was 98%. conclusion: according to the findings of the present study, in patients suspected of pneumonia, lus is more sensitive and specific in the diagnosis of pneumonia and is less time-intensive and costly. additionally, the ultrasound device is easily portable and accessible. it can be widely used and does not have the secondary side effects of ionizing radiation in patients. however, the technician’s skill in performing ultrasound is a matter of importance.