A practical approach to coronavirus disease 2019 pneumonia imaging

Coronavirus disease 2019 (COVID-19) was first recognized in China in December 2019 and then was declared as a pandemic by the WHO in March 2020. The most established diagnostic tool is the real-time reverse transcription-PCR, which is highly specific but has a relative low sensitivity. False-negative results and consequently the need to repeat the test and relative delay in conclusive results are a real diagnostic problem. Other laboratory marker tests are more suggestive than diagnostic. All these factors have made computed tomographic (CT) imaging in cases of clinically suspected COVID-19 a routine and an integral part of the algorithm for disease diagnosis in many countries including Egypt. The role of CT is well established in detecting the presence of a lesion, discriminating different types of lesions, and assessing distribution, severity, complications, associated extrapulmonary chest manifestations, and follow-up of cases. The CT picture of COVID-19 is known to reflect atypical pneumonia and/or organizing pneumonia. The presence of ground-glass opacities, consolidation, or crazy paving in bilateral subpleural distribution with predominant lower lobes affection is considered typical for COVID-19. Based on our experience, in the context of the current pandemic, the presence of CT inflammatory changes in a patient with clinical suspicion of COVID-19 should be considering as an alarming sign for the presence of COVID infection as the cause of ground-glass opacities. A negative CT report for COVID-19 should only be considered in cases of normal CT or if CT lesions do not represent inflammatory changes.