Journal Article

The role of lung ultrasound B-lines and serum KL-6 in the screening and follow-up of rheumatoid arthritis patients for an identification of interstitial lung disease: review of the literature, proposal for a preliminary algorithm, and clinical application to cases

Lin, Qisheng, Xie, Xuezhen, Hoffmann-Vold, Anna-Maria, Zhang, Guohong, Du, Guangzhou, Chen, Shaoqi, Zheng, Shaoyu, Furst, Daniel E., Zhuang, Jinghua, Matucci-Cerinic, Marco, Wang, Yukai, Zheng, Kedi, Hu, Shijian, Lin, Jianqun, Zhang, Weijin

2021

Overview

Screening and follow-up of interstitial lung disease associated with rheumatoid arthritis (RA-ILD) is a challenge in clinical practice. In fact, the majority of RA-ILD patients are asymptomatic and optimal tools for early screening and regular follow-up are lacking. Furthermore, some patients may remain oligosymptomatic despite significant radiological abnormalities. In RA-ILD, usual interstitial pneumonia (UIP) is the most frequent radiological and pathological pattern, associated with a poor prognosis and a high risk to develop acute exacerbations and infections. If RA-ILD can be identified early, there may be an opportunity for an early treatment and close follow-up that might delay ILD progression and improve the long-term outcome. In connective tissue disease–associated interstitial lung disease (CTD-ILD), lung ultrasound (LUS) with the assessment of B-lines and serum Krebs von den Lungen-6 antigen (KL-6) has been recognized as sensitive biomarkers for the early detection of ILD. B-line number and serum KL-6 level were found to correlate with high-resolution computed tomography (HRCT), pulmonary function tests (PFTs), and other clinical parameters in systemic sclerosis–associated ILD (SSc-ILD). Recently, the significant correlation between B-lines and KL-6, two non-ionizing and non-invasive biomarkers, was demonstrated. Hence, the combined use of LUS and KL-6 to screen and follow up ILD in RA patients might be useful in clinical practice in addition to existing tools. Herein, we review relevant literature to support this concept, propose a preliminary screening algorithm, and present 2 cases where the algorithm was used.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Arthritis / Asymptomatic / B-lines / Clinical medicine / Complications and side effects / Diagnostic tests / Evaluation / High-resolution computed tomography / Identification and classification / KL-6 / Lung diseases / Lung diseases, Interstitial / Lung ultrasound / Medical diagnosis / Medical prognosis / Medicine / Medicine & Public Health / Mortality / Orthopedics / Pneumonia / Pulmonary function tests / Radiation / Review / Rheumatoid arthritis / Rheumatoid arthritis–associated interstitial lung disease / Rheumatology / Tomography / Tumor necrosis factor-TNF / Ultrasonic imaging