Diagnostic performance of lung ultrasound and its association with bacterial and viral pneumonia in children

Background: Pediatric pneumonia remains a major cause of childhood morbidity and mortality. Although chest radiography (CXR) is commonly used for imaging, lung ultrasound (LUS) provides a radiation-free bedside alternative. Its potential role in differentiating bacterial from viral pneumonia requires further evaluation. Aims and Objectives: This study aimed to determine the diagnostic performance of LUS and its potential role in identifying the etiology of pediatric pneumonia. Materials and Methods: A hospital-based cross-sectional study was conducted over 1 year at Assam Medical College and Hospital, enrolling 150 children aged 1 month–12 years with clinically diagnosed pneumonia. LUS was performed using a high-frequency linear transducer, assessing consolidations, pleural effusion, and B-lines. Nasopharyngeal swabs Indian Council of Medical Research reverse transcription polymerase chain reaction and clinical data stratified cases into bacterial (n=62) and viral (n=88) groups. Sensitivity and specificity of LUS were compared with CXR using Chi square and t-tests (P < 0.05). Results: Using CXR as the reference standard, LUS demonstrated a sensitivity of 96.16% (95% CI: 93.15–100%) and specificity of 94.90% (95% CI: 88.49–98.32%) for pneumonia. Consolidations >10 mm (43.55% vs. 0%; P < 0.0001) and pleural effusion (33.87% vs. 5.68%; P < 0.0001) were more frequent in bacterial pneumonia, whereas B-lines were more common in viral pneumonia (54.55% vs. 19.35%; P < 0.0001). Fever and crackles were significantly more frequent in the bacterial group. Conclusion: LUS demonstrated high diagnostic performance for pediatric pneumonia. Distinct sonographic patterns differed significantly between bacterial and viral groups, suggesting that LUS may serve as a useful bedside adjunct for diagnosis and etiological assessment when interpreted alongside clinical and microbiological findings.