Coronavirus Disease (COVID-19) Compared with Middle East Respiratory Syndrome (MERS): A Radiological Perspective.

Background: This study aims to describe the radiological findings in chest radiographs (CXRs) of patients with coronavirus disease (COVID-19) and the Middle East respiratory syndrome (MERS) and to compare the radiological patterns of the two diseases.

Methods: A retrospective cohort study was conducted in a tertiary care hospital in the Southern region of Saudi Arabia. The CXRs were evaluated for the presence and distribution of ground-glass opacities (GGO), consolidation, pleural effusions, pneumothorax, cavitation, and nodules.

Results: A total of 120 CXRs from 15 MERS and six COVID-19 patients were assessed. In the first available CXR, GGO was present in 11 (73%) of the MERS patients (18% located in the middle zones and 67% located peripherally) and in 100% of COVID-19 patients (peripheral and middle zone involvement in all patients). In the first available CXRs, consolidation was present in 10 MERS patients (67%) and in all six COVID-19 patients, while it was present in all patients of both groups when all the available CXRs were considered. Confluent consolidation was present in 47% of the MERS patients and 50% of COVID-19 patients. All the fatal cases had confluent consolidation and radiological signs of acute respiratory distress syndrome (ARDS). Pneumothorax was present in 13% of patients, with 100% mortality, and pleural effusion was present in 47% of patients, with 57% mortality. Lung nodules were present in one patient of each group.

Conclusion: COVID-19 patients showed earlier development of GGO and consolidation with greater involvement of the middle and peripheral lung zones. Confluent consolidation and ARDSlike radiological findings were associated with high mortality. Pneumothorax and pleural effusions were more frequent in MERS patients, with high associated mortality.