COVID-19 and interstitial lung diseases

Challenges in the differential diagnosis of SARS-CoV-2-induced viral pneumonia and interstitial lung diseases (ILD), especially those that were previously undiagnosed, newly-onset or acute, have been identified based on data from the COVID-19 pandemic. Viral infections are known to be a risk factor for the development and exacerbation of ILD. In COVID-19, acute lung injury occurs with the development of inflammatory changes in the pulmonary interstitium, which may lead to the fibrotic formation of the lung tissue. Currently, the problem of ILD and COVID-19 remains extremely urgent, given the difficulties in differential diagnosis of the acute phase of COVID-19, post-COVID-19 changes, and various nosological forms of ILD, and the significant impact of COVID-19 on the course of an underlying ILD. The aim of this review was to highlight the features of the differential diagnosis of ILD and viral pneumonia caused by SARS-CoV-2, and to investigate the impact of COVID-19 on the course of ILD. Conclusion. The differential diagnosis of ILD and COVID-19 viral pneumonia should consider a combination of features of the disease onset, clinical findings, changes on high-resolution computed tomography (HRCT), laboratory data, and identification of SARS-CoV-2.