Coronavirus disease 2019 (COVID-19) in patients with systemic autoimmune diseases or vasculitis: radiologic presentation.

Coronavirus disease 2019 (COVID-19) has transformed into a worldwide challenge, since its outbreak in December 2019. Generally, patients with underlying medical conditions are at a higher risk of complications and fatality of pneumonias. Whether patients with systemic autoimmune diseases or vasculitides, are at increased risk for serious complications associated with COVID-19, is not established yet. Computed tomography (CT) has been employed as a diagnostic tool in the evaluation of patients with clinical suspicion of severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) infection with a reported sensitivity of higher than reverse transcription polymerase chain reaction (RT-PCR) test. Multifocal bilateral ground-glass opacities (GGOs) with peripheral and posterior distribution and subsequent superimposition of consolidations are considered the main imaging features of the disease in chest CT. However, chest CT images of underlying rheumatologic or autoimmune diseases or vasculitides, such as systemic sclerosis, systemic lupus erythematosus, rheumatoid arthritis, Behçet disease, and granulomatosis with polyangiitis, especially those with extensive lung involvement can overshadow or obliterate features of COVID-19. In addition, CT findings of such diseases may resemble manifestations of COVID-19 (such as ground glass opacities with or without superimposed consolidation), making the diagnosis of viral infections, more challenging on imaging. Comparing the imaging findings with prior studies (if available) for any interval change is the most helpful approach. Otherwise, the diagnosis of COVID-19 in such patients must be cautiously made according to the clinical context and laboratory results, considering a very high clinical index of suspicion on imaging.