Using thoracic ultrasound to detect interstitial lung disease in patients with rheumatoid arthritis: a protocol for the diagnostic test accuracy AURORA study

Abstract

IntroductionPulmonary diseases are significant contributors to morbidity and mortality in patients with rheumatoid arthritis (RA). RA-associated interstitial lung disease (RA-ILD) may be prevalent in up to 30% and clinically evident in 10% of patients with RA. Feasible methods to detect concomitant ILD in RA are warranted. Our objective is to determine the diagnostic accuracy of thoracic ultrasound (TUS) for ILD in patients with RA with respiratory symptoms, by using chest high-resolution CT (HRCT) as the reference standard. Further, we aim to evaluate the diagnostic accuracy for the promising blood biomarkers surfactant protein-D and microfibrillar-associated protein 4 in the detection of ILD in this group of patients.Methods and analysisBy use of a standardised 14 zone protocol patients suspected of having RA-ILD will undergo TUS as index test performed by a junior resident in rheumatology (BKS), who is certified by the European Respiratory Society in performing TUS assessments. Participants form a consecutive series of up to 80 individuals in total. The anonymised TUS images will be stored and scored by the junior resident as well as two senior rheumatologists, who have received training in TUS, and a TUS-experienced pulmonologist. HRCT will be used as the gold standard for ILD diagnosis (reference standard). The two basic measures for quantifying the diagnostic test accuracy of the TUS test are the sensitivity and specificity in comparison to the HRCT.Ethics and disseminationData will be collected and stored in the Research Electronic Data Capture database. The study is approved by the Committees on Health Research Ethics and the Danish Data Protection Agency. The project is registered at clinicaltrials.gov (NCT05396469, pre-results) and data will be published in peer-reviewed journals.

Do Ultrasound Lung Abnormalities Correlate to Biomarkers and Male Gender in Rheumatoid Arthritis Patients? A Monocentric Cross-Sectional Study

“…The sample size was calculated according to the methodology suggested in recent studies on ILD in RA [ 32 , 47 ]: 155 patients in the studied population achieved >80% statistical power, with an α level of 0.05 and beta 0.2.…”

“…Even if air is not a favorable medium for transmission of LUS waves, the identification of vertical comet artifacts (B lines, due to fluid and collagen accumulation) and pleura layer morphological abnormalities has shown good sensitivity and concordance with the extent and severity of ILD in HRCT in autoimmune diseases and RA [ 30 , 31 , 32 , 33 ].…”

Pleural clinic: where thoracic ultrasound meets respiratory medicine

“…In patients with rheumatoid arthritis, US can accurately detect ILDs, and the number of B-lines has been associated with the degree of functional impairment and the levels of circulating inflammatory markers ( 27 ). The sensitivity and specificity of TUS in comparison to HRCT are currently under investigation ( 28 ). Similarly, US assessment has been effectively employed as a diagnostic tool for COVID-19 pneumonia, given the predominant involvement of the lung periphery ( 29 ).…”

Design of ANCHOR-RA: a multi-national cross-sectional study on screening for interstitial lung disease in patients with rheumatoid arthritis

“…The gold standard for radiological assessment of ILD is a high-resolution computed tomography (HRCT) scan [21,22]. Evidence is emerging on the use of lung ultrasound as a screening tool [23][24][25][26][27], but more data are needed to establish its accuracy in the detection of RA-ILD. The high prevalence of RA and lower prevalence of RA-ILD means that it would be inefficient and likely not feasible for all patients with RA to undergo HRCT, but there is no consensus as to which patients should be screened.…”