The Role of Nailfold Capillaroscopy in Evaluating Patients with Interstitial Lung Disease Related to Connective Tissue Disease.

Capillaroscopy is a non-invasive and safe imaging method that allows the evaluation of the microcirculation of the small vessels of the skin. The method's main advantage is the early detection of microvascular changes that may occur in certain connective tissue diseases (CTDs). Today, the presence of specific autoantibodies and capillaroscopic findings are generally accepted and emerge as a powerful diagnostic tool for detecting underlying CTDs in patients with Raynaud's phenomenon. The role of capillaroscopy has also been investigated in patients with CTD and interstitial lung disease (ILD). In these patients, lung involvement is considered one of the most severe complications, potentially leading to significant morbidity and mortality. So far, studies have shown an association of the scleroderma pattern in capillaroscopy with lung involvement in Scleroderma patients. Although there are studies on the association of capillary findings in patients with other CTDs, further efforts are needed to evaluate this technique and produce high-performance algorithms in the early detection of involvement and the progression of (CTD) related ILD (CTD-ILD). The present study aims to perform capillaroscopy in CTDILD patients with different imaging patterns and to correlate the method's findings with those found in high-resolution computed tomography, pulmonary tests, and the immunological profile of patients. Furthermore, the impact of ILD treatment on the capillaroscopic findings will be evaluated.