Lung Ultrasound-A Supplementary Tool for the Diagnosis of Pulmonary Tuberculosis in Children.

Abstract

Background: There are logistic problems in obtaining adequate microbiological samples for the diagnosis of pulmonary tuberculosis (PTB) in children, globally. Most studies on ultrasound have evaluated mediastinal nodes in children with tuberculosis (TB), but very few studies are available on lung ultrasound (LUS) appearances in proven PTB.

Purpose: To study the LUS appearances in children with microbiologically proven PTB and to assess the inter-observer agreement.

Materials and methods: Thirty children with microbiologically proven PTB, were evaluated prospectively on LUS and chest radiograph (CR) in Radiology department of a tertiary care hospital, from November 2019 to November 2021. CR was interpreted by an experienced Radiologist (R2); LUS was conducted by a Radiology resident (R1), who was blinded to CR findings; and findings were recorded. Archived static images/videos of LUS were interpreted by R2 after a month, to avoid bias; and findings were recorded.

Results: Composite LUS finding of either consolidation and subpleural nodule (SUN) was detected in 29/30 (96.7%) children with lower zone predominance (70%). Miliary pattern was observed on LUS in 11/30 (33.3%) children, but their CR was normal. Consolidation was detected on LUS in a significantly higher proportion of children (83.3%) than on CR (43.3%). Inter-observer agreement calculated for detection of consolidation and pleural effusion was k = 0.88, for B lines k = 0.79, confluent B lines k = 0.75, miliary nodules k = 0.70 and SUN k = 0.57.

Conclusion: We conclude that in low-resource endemic areas, LUS by virtue of being non -invasive and not using ionizing radiation, can be a useful supplementary tool in the diagnosis of childhood PTB.