Acute exacerbation (AE) is a possible manifestation of interstitial lung diseases (ILD) associated to very high mortality. It's defined as clinically significant respiratory deterioration with evidence of new widespread alveolar abnormalities on computed tomography scan. AE is better described in idiopathic pulmonary fibrosis (IPF) but also reported in ILD secondary to connective tissue diseases (CTD) and vasculitis. The main features and the real clinical impact of this severe complication in these patients are not well defined. Aim of our study was to prospectively investigate the incidence, clinical features and outcome of AE in a population of patients with ILD related to CTD and vasculitis. We consecutively enrolled all patients, with ILD secondary to rheumatic systemic diseases, referring to our multidisciplinary outpatient clinic for rare lung diseases. All patients were followed for at least 12 months (range, 12-36 months). At baseline, all patients underwent to a core set of laboratory investigations and periodically followed; data about demographic, disease onset, clinical, serological and therapeutic features were also recorded. AE occurred in 9/78 patients, with an incidence of 5.77/100 patients/year, and 5/9 patients died because of AE. The baseline value of DLCO was significantly associated to the risk of AE at Cox regression. In patients with ILD related to rheumatic systemic diseases AE can occur with an incidence similar to IPF. Rheumatologists should carefully consider this life-threatening complication as a possible natural course of all patients with ILD secondary to systemic rheumatic disease.

In 2019, the novel SARS-CoV-2 infection emerged, causing the disease called COVID-19, which primarily affects the respiratory tract and lung at alveolar and interstitial levels. Systemic sclerosis (SSc) is an autoimmune connective disease characterized by vascular abnormalities and diffuse and progressive fibrosis of the skin and internal organs. Raynaud phenomenon (RP) occurs in virtually all patients affected by SSc and, in most cases, is an onset symptom of the disease; that is, RP may appear several years before overt illness. Although the exact pathophysiologic pathways leading to RP and SSc are still unknown, several infectious agents, especially viruses, have been suggested as possible triggering factors. Here, the authors describe the first case of RP secondary to SSc following SARS-CoV-2 infection.