A new study found that lung ultrasound may be an effective screening tool for detecting interstitial lung disease in patients with rheumatoid arthritis, outperforming traditional symptom-based assessments.
In the study, published in RMD Open, investigators reported that lung ultrasound (LUS) exhibited an area under the receiver operating characteristic (AUROC) curve greater than 0.9 for predicting both clinical and subclinical interstitial lung disease (ILD) associated with rheumatoid arthritis (RA-ILD), demonstrating superior diagnostic accuracy compared with dyspnea and cough assessments.
The investigators conducted a cross-sectional study involving 116 adult patients with RA who underwent high-resolution computed tomography (HRCT) scans, pulmonary function tests (PFT), and LUS. They utilized a 72-zone scanning protocol to assess B-lines—vertical artifacts indicating interstitial lung abnormalities. HRCT confirmed RA-ILD in 11.8% of patients, whereas 5% exhibited subclinical interstitial lung changes. B-line presence correlated strongly with HRCT-confirmed ILD (P < .001), whereas symptom-based measures such as the modified Medical Research Council (mMRC) dyspnea scale and Visual Analog Scale (VAS) for cough demonstrated weak predictive value.
Sensitivity and specificity analyses revealed that using a threshold of five B-lines on LUS resulted in 100% sensitivity for detecting advanced ILD and 94.4% sensitivity for identifying subclinical or clinical ILD. In contrast, symptom-based screening was less reliable, with dyspnea assessment detecting RA-ILD at 61.5% sensitivity and cough assessment detecting the condition at 53.9% sensitivity.
LUS was easily integrated into routine checkups, avoiding the inconvenience of additional return visits and lengthy procedures associated with CTs and PFTs.
"LUS is a promising tool for early detection of RA-ILD, outperforming symptom-based questionnaires or the presence of dyspnoea or cough," said lead study author Marie Vermant, of the Department of Chronic Diseases and Metabolism at Katholieke Universiteit Leuven in Belgium, and her colleagues.
While LUS presented an accessible, radiation-free, and cost-effective alternative to HRCT for ILD screening, the investigators emphasized that further studies are needed to establish standardized protocols and define optimal B-line thresholds for clinical use.
The authors reported no competing interests.