Transthoracic sonography may be a sensitive, non-invasive tool for identifying and monitoring early-stage interstitial lung disease in patients with rheumatoid arthritis, systemic sclerosis and systemic lupus erythematosus, according to researchers from the Medical University of Graz in Graz, Austria.
The researchers enrolled 25 patients diagnosed with rheumatoid arthritis (RA), 14 patients with systemic sclerosis (SSc) and six patients with systemic lupus erythematosus (SLE) according to American College of Rheumatology criteria. Forty healthy participants were also recruited as controls.
No patients reported pulmonary symptoms, and pulmonary function tests showed normal forced vital capacity and diffusing capacity of the lung in all patients.
The patients were scanned with high-resolution CT (HRCT), and images were interpreted by one of the authors. Healthy control participants were not examined with HRCT for ethical reasons. All participants were examined with thoracic ultrasound by two additional authors blinded to the HRCT results. Patients also underwent lung sonography. Through ultrasound, the researchers documented patients’ B-lines, subpleural nodes and any irregularities of the pleura.
On HRCT, seven of the patients with RA, nine of the patients with SSc and four of the patients with SLE showed signs of pulmonary fibrosis. Using ultrasound, the researchers observed comet-tail artifacts or B-patterns in all patients with HRCT-confirmed interstitial lung disease (ILD) and in 12% of participants with normal CT scans.
The researchers also observed subpleural nodes in 55% of patients with ILD compared with 17% in the non-ILD group, and 95% of patients with ILD showed pleural irregularities compared with 5% of participants without ILD.
Pleural nodes were seen in all patients with RA and ILD with ultrasound, but in only 22% of patients with SSc and 50% of patients with SLE. An irregular pleural line greater than 3 mm was observed in all of the patients with SLE and ILD and in 86% of patients with RA. – by Shirley Pulawski
Disclosures: The authors report no relevant financial disclosures.