COVID-19 pneumonia: CT findings of 122 patients and differentiation from influenza pneumonia

Abstract

Objectives To investigate the clinical and chest CT characteristics of COVID-19 pneumonia and explore the radiological differences between COVID-19 and influenza. Materials and methods A total of 122 patients (61 men and 61 women, 48 ± 15 years) confirmed with COVID-19 and 48 patients (23 men and 25 women, 47 ± 19 years) confirmed with influenza were enrolled in the study. Thin-section CT was performed. The clinical data and the chest CT findings were recorded. Results The most common symptoms of COVID-19 were fever (74%) and cough (63%), and 102 patients (83%) had Wuhan contact. Pneumonia in 50 patients with COVID-19 (45%) distributed in the peripheral regions of the lung, while it showed mixed distribution in 26 patients (74%) with influenza (p = 0.022). The most common CT features of the COVID-19 group were pure ground-glass opacities (GGO, 36%), GGO with consolidation (51%), rounded opacities (35%), linear opacities (64%), bronchiolar wall thickening (49%), and interlobular septal thickening (66%). Compared with the influenza group, the COVID-19 group was more likely to have rounded opacities (35% vs. 17%, p = 0.048) and interlobular septal thickening (66% vs. 43%, p = 0.014), but less likely to have nodules (28% vs. 71%, p < 0.001), tree-in-bud sign (9% vs. 40%, p < 0.001), and pleural effusion (6% vs. 31%, p < 0.001).Conclusions There are significant differences in the CT manifestations of patients with COVID-19 and influenza. Presence of rounded opacities and interlobular septal thickening, with the absence of nodules and tree-in-bud sign, and with the typical peripheral distribution, may help us differentiate COVID-19 from influenza. Key Points • Typical CT features of COVID-19 include pure ground-glass opacities (GGO), GGO with consolidation, rounded opacities, bronchiolar wall thickening, interlobular septal thickening, and a peripheral distribution. • Presence of rounded opacities and interlobular septal thickening, with the absence of nodules and tree-in-bud sign, and with the typical peripheral distribution, may help us differentiate COVID-19 from influenza.

Chest CT Imaging Signature of Coronavirus Disease 2019 Infection

“…Risk of bias with respect to patient spectrum was rated "unclear" in two studies, 34,39 because the number of patients with normal chest CT imaging findings was not reported. Risk of bias with respect to flow and timing was rated "unclear" in 24 studies, 15,16,[18][19][20][21][22][23][24][26][27][28][29][30][31][32][34][35][36][37][38][39][40][41] because these studies did not report the time interval between CT scanning and RT-PCR/gene sequencing. Risk of bias with respect to flow and timing was rated "high" in two studies, 14,25 because the time interval between CT and RT-PCR procedures exceeded 72 hours (maximum of 7 and 14 days, respectively).…”

Chest CT in COVID-19 pneumonia: A review of current knowledge

“…However, the peripheral location of the lesions, involvement of the five lobes, the presence of thin reticulations and peribronchovascular thickening would be more frequently found in COVID-19 pneumonitis [17,18]. In influenza pneumonia, nodular or micronodular tree-in-bud pattern may be more common, as may pleural effusions [19].…”

A Telemedicine Approach to Covid-19 Assessment and Triage

“…Covid-19 pneumonia typically presents on CT scans as a bilateral ground glass appearance, with or without consolidation [ 73 , 74 , 75 ]. In Covid-19, lesions are often distributed in peripheral and subpleural areas of the lung [ 76 ].…”