Lung Ultrasound in Children With Systemic Juvenile Idiopathic Arthritis-Associated Interstitial Lung Disease

Abstract

Objective: Systemic juvenile idiopathic arthritis (JIA) associated with lung disease (JIA-LD) is a potentially life threating complication in children with systemic JIA. Although high-resolution computed tomography (HRCT) is considered the gold standard imaging modality for evaluating interstitial lung disease (ILD), lung ultrasound (US) has shown utility for ILD screening in adults with connective tissue diseases at lower cost and without using ionizing radiation. The goals of this pilot study were to describe lung US features in children with known systemic JIA-LD and to assess the feasibility of lung US in this population.

Methods: Children age <18 years with systemic JIA-LD and healthy controls were enrolled. Lung US acquisition was performed at 14 lung positions. Demographic, clinical, and HRCT data were collected and reviewed. Feasibility was assessed through patient surveys. Lung US findings were qualitatively and semiquantitatively assessed and compared to HRCT findings.

Results: Lung US was performed in 9 children with systemic JIA-LD and 6 healthy controls and took 12 minutes on average to perform. Lung US findings in systemic JIA-LD included focal to diffuse pleural irregularity, granularity, and thickening, with associated scattered or coalesced B-lines, and subpleural consolidations. Lung US findings appeared to correspond to HRCT findings.

Conclusion: Lung US in systemic JIA-LD reveals highly conspicuous abnormalities in the pleura and subpleura that appear to correlate with peripheral lung findings on HRCT. Lung US is a feasible imaging tool in children even from an early age. This study suggests a potential role of lung US in systemic JIA-LD screening, diagnosis, and/or prognostication.

Figure 1.

Normal and sJIA-LD on Lung Ultrasound. LUS in a healthy control (a) and sJIA-LD (b-d). (a) Control patient with normal pleural surface denoted by a thin hyperechoic pleural line (grey arrows). (b) Diffuse pleural irregularity, coarse granularity, and thickening (arrowheads), and associated B-lines (arrows). (c) Consolidation at the posterior lung base seen as hepatization (arrowheads) adjacent to the diaphragm (dotted arrows). (d) Subpleural consolidations (arrowheads) and associated dense B-lines (arrows). Asterisk = ribs. LUS = lung ultrasound.

Figure 2.

Paired LUS and HRCT findings in and sJIA-LD. Lung ultrasound (LUS) and high-resolution computer tomography (HRCT) images of the lungs in sJIA-LD Top: Focal pleural irregularities (arrowheads) and scattered B-lines (arrow) on LUS (left) that correspond to subpleural interlobular septal thickening and reticulation (arrow) on HRCT (right). Bottom. Diffuse pleural irregularity with a fine granular pattern and dense B-line confluence on LUS (left) that corresponds to an area of minimal subpleural consolidation (black arrow) adjacent to an area of more pronounced subpleural consolidation (white arrow) on HRCT (right). Asterisk = ribs.