Assessment of Bedside Ultrasound in Patients with Pneumonia and its Correlation with Chest Radiography Rale Score and Chest Computed Tomography

INTRODUCTION: Pneumonia is an inflammatory infiltrate of the alveolar airspace. It remains a common infective cause for admission to ICU (Intensive Care Unit). It accounts for a significant global burden of disease especially prevalent in low and middle income nations. Plain radiograph remains a viable option in such a situation, but in some scenarios, it fails to delineate the exact location and involvement. CXR (Chest X ray) is recommended and most frequently used as the first imaging approach for diagnosing pneumonia, but it is important to note that the CXR may miss a significant number of early pneumonia cases. LUS is being increasingly evaluated nowadays as a bedside method, and results have been encouraging. Some recent studies have shown that LUS has better sensitivity than CXR in the diagnosis of pleural effusion.(1) OBJECTIVE: To evaluate the diagnostic utility of bedside lung ultrasound in patients with pneumonia, and its correlation with chest radiography and chest computed tomography. MATERIALS AND METHODS: INCLUSION CRITERIA: 1. All patients with suspected pneumonia who needed hospital admission. 2. Patients aged 18 years or above. EXCLUSION CRITERIA: 1. Children less than 18 years of age. 2. Pregnant women. 3. Patients having subcutaneous emphysema over the chest. 4. Patients with pneumonia in whom diagnosis could be made on the basis of Chest X ray and CT chest was not indicated. RESULTS AND OBSERVATIONS: LUS showed high values of sensitivity, specificity, diagnostic accuracy and good agreement with pneumonia as compared to CXR. B lines and LUS did not show statistical significant results between pneumonia and non pneumonia cases. Shred sign, hepatisation sign and dynamic air bronchogram have shown to have a good diagnostic accuracy in predicting pneumonia, with dynamic air bronchogram being the most specific. Cxray RALE score and LUS showed positive correlation (p<0.0001) and median RALE score is on lower side in patients with pneumonia. Sensitivity, specificity, positive predictive value and negative predictive value of B lines, Air bronchogram, Shred sign and Hépatisation for predicting pneumonia. CONCLUSION: In our study we observed positive correlation between RALE score and LUS in patients with pneumonia and patients with pneumonia had lower RALE score. The strengths of our study include large sample size, comparison of CXR and LUS findings with CT scan which is the gold standard. LUS is a powerful tool in the hands of intensivist to make early diagnosis of pneumonia with high accuracy.