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Published on: December 19, 2020
Delayed Clearance of Viral RNA in Sputum for Severity COVID-19 Patients with Initial High Viral Load
Hong Zhao1, Huilan Tu1, Xia Yu1
1State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310003, People's Republic of China.
Aim:
To analyze the possible risk factors of delayed virus clearance in hospitalized patients with coronavirus disease 2019 (COVID-19).
Methods:
Retrospective analysis of patients with COVID-19 admitted to the isolation wards from our hospital from 19th Jan 2020 to 18th March 2020. We were collected patient's data including demographic, epidemiologic, and clinical information, as well as laboratory and radiologic findings. The possible confounding risk factors for prolonged viral RNA shedding of COVID-19 during hospitalization were explored by univariate analysis and any variables with a p value less than 0.05 after univariate analysis were included in a subsequent multivariate logistic regression model analysis.
Results:
The 104 patients included 30 mild patients and 74 severe or critically ill patients. The median duration of viral RNA positivity in sputum was 11 days, and the longest duration of viral RNA positivity was 49 days after admission. Multivariate analysis shown that the used with darunavir/cobicistat treatment (odds ratio [OR]: 4.25, 95% confidence interval [CI]: 1.25-14.42, p = 0.020), duration of fever (OR: 1.15, 95% CI: 1.03-1.30, p = 0.015) and time to radiological improvement (OR: 1.14, 95% CI: 1.01-1.30, p = 0.033) were associated with delayed clearance of SARS-CoV-2 in sputum from COVID-19 patients. Then adjusted in the multivariate binary logistic regression analysis model in severe COVID-19 and found that critical COVID-19 patients (OR: 13.25, 95% CI: 1.45-12.07, p = 0.022), lower virus cycle threshold (CT) values of RT-PCR (OR: 0.96, 95% CI: 0.93-0.99, p = 0.004) and used with darunavir/cobicistat treatment (OR: 8.44, 95% CI: 2.21-32.28, p = 0.022) were associated with delayed clearance of SARS-CoV-2 in sputum from COVID-19 patients.
Conclude:
Clearance of viral RNA in sputum was delayed in severe COVID-19 patients, especially with lower virus CT value. And antivirals with darunavir/cobicistat has little advantage in eliminating SARS-CoV-2.
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