Chest CT for early detection and management of coronavirus disease (COVID-19): a report of 314 patients admitted to Emergency Department with suspected pneumonia.

PURPOSE: The purpose of our study was to assess the potential role of chest CT in the early detection of COVID-19 pneumonia and to explore its role in patient management in an adult Italian population admitted to the Emergency Department. METHODS: Three hundred and fourteen patients presented with clinically suspected COVID-19, from March 3 to 23, 2020, were evaluated with PaO2/FIO2 ratio from arterial blood gas, RT-PCR assay from nasopharyngeal swab sample and chest CT. Patients were classified as COVID-19 negative and COVID-19 positive according to RT-PCR results, considered as a reference. Images were independently evaluated by two radiologists blinded to the RT-PCR results and classified as "CT positive" or "CT negative" for COVID-19, according to CT findings. RESULTS: According to RT-PCR results, 152 patients were COVID-19 negative (48%) and 162 were COVID-19 positive (52%). We found substantial agreement between RT-PCR results and CT findings (p < 0.000001), as well as an almost perfect agreement between the two readers. Mixed GGO and consolidation pattern with peripheral and bilateral distribution, multifocal or diffuse abnormalities localized in both upper lung and lower lung, in association with interlobular septal thickening, bronchial wall thickening and air bronchogram, showed higher frequency in COVID-positive patients. We also found a significant correlation between CT findings and patient's oxygenation status expressed by PaO2/FIO2 ratio. CONCLUSION: Chest CT has a useful role in the early detection and in patient management of COVID-19 pneumonia in a pandemic. It helps in identifying suspected patients, cutting off the route of transmission and avoiding further spread of infection.

SARS-CoV-2 evasion from ADAR hyper-editing is both genome-encoded and sustained by the virus replication strategy (preprint)

SARS-CoV-2 is threatening the human society because of its capability to subvert antiviral defenses, causing cytokine hyper-activation and prolonged damage in multiple tissues with unpredictable outcomes in the mid-long term. Here, we evaluated the role of ADAR, an interferon-stimulated gene able to control the activation of the immune system and to directly modify exogenous dsRNAs, during in-vivo infection by SARS-CoV-2. After accurate analysis of 863 RNA-seq samples from different species, we identified ADAR-mediated hyper-editing of SARS-CoV-2 only in 49 human datasets at a low level (0.036‰ hyper edited reads on average) and preferentially on ORF6. Conversely, in mouse datasets we found abundant hyper-editing of viral reads (up to 1.16‰). The analysis of dinucleotide frequency along the ORFs of α, β, δ and γ coronaviruses highlighted the evolutionary pressure of ADAR enzymes, suggesting that the SARS-CoV-2 resistance to hyper-editing is both genome-encoded and supported by the viral transcription strategy.

Chest CT For Early Detection And Management Of Coronavirus Disease (COVID-19): A Report Of 314 Patients Admitted To Emergency Department With Suspected Pneumonia (preprint)

PURPOSE: The purpose of our study was to assess the potential role of chest CT for the early detection of COVID-19 pneumonia and to explore its role in patient management in an adult Italian population admitted to the Emergency Department.METHODS: 314 patients presented with clinically suspected COVID-19, From March 3 rd to 23 th 2020, were evaluated with PaO2/FIO2 ratio from arterial blood gas, RT-PCR assay from nasopharyngeal swab sample and chest CT. Patients were classified as COVID-19 negative and COVID-19 positive according to RT-PCR results, considered as a reference. Images were independently evaluated by two radiologists blinded to the RT-PCR results and classified as “CT positive” or “CT negative” for COVID-19, according to CT findings.RESULTS: According to RT-PCR results, 152 patients were COVID-19 negative (48%) and 162 were COVID-19 positive (52%). We found substantial agreement between RT-PCR results and CT findings (p<0.000001), as well as an almost perfect agreement between the two readers. Mixed GGO and consolidation pattern with peripheral and bilateral distribution, multifocal or diffuse abnormalities localized in both upper and lower lung, in association with interlobular septal thickening, bronchial wall thickening and air bronchogram, showed higher frequency in COVID positive patients. We also found a significant correlation between CT findings and patient’s oxygenation status expressed by PaO2/FIO2 ratio.CONCLUSION: Chest CT is a vital component in the early detection and in patients management of COVID-19 pneumonia in a pandemic. It allows to identify suspected patients, cutting off the route of transmission and avoiding further spread of infection.