Role of Lung Ultrasound in Early Diagnosis of Systemic Sclerosis-Related Interstitial Lung Disease

Abstract

Interstitial lung disease (ILD) is a major extra-articular manifestation of systemic sclerosis (SSc), significantly contributing to morbidity and mortality. Early detection and close monitoring of patients at high risk of progression are critical for establishing the need for targeted treatment with immunomodulatory and antifibrotic drugs that have the potential to alter the course of the disease. Although the predictive value of high-resolution computed tomography (HRCT) is undeniable, it increases the risk of cancer in SSc-ILD patients with a propensity for developing cancer due to medication overuse and radiation exposure. Lung ultrasonography (LUS) is an intriguing alternative technology in this context, providing a non-invasive and non-radiating evaluation that can be performed prior to other imaging techniques, such as a CT scan, to detect interstitial abnormalities within the subpleural space. Vertical artifacts such as B lines and pleural line modifications have a strong link with the presence of ILD on HRCT and the extent and severity of the disease, with sensitivity and negative predictive values of up to 100%. In the past decades, LUS has been shown to be a cost-effective and repeatable procedure when combined with pulmonary function tests as a primary assessment, limiting the frequency of HRCT application and minimizing radiation exposure that contributes to the probability of cancer development and progression. In this review, we have provided an etiological background for pulmonary involvement in SSc, screening modalities for ILD in SSc, and a thorough description of LUS findings and scoring systems as a point-of-care diagnostic tool in SSc-ILD.