Risk factors for delayed negative conversion of SARS-CoV-2 in patients with COVID-19 pneumonia: A retrospective cohort study

Abstract

The epidemic of coronavirus disease 2019 (COVID-19) began in China and had spread rapidly to many other countries. This study aimed to identify risk factors associated with delayed negative conversion of SARS-CoV-2 in COVID-19 patients. In this retrospective single-center study, we included 169 consecutive patients with confirmed COVID-19 in Zhongnan Hospital of Wuhan University from January 15thto March 2nd. The cases were divided into two groups according to the median time of SARS-CoV-2 negative conversion. The differences between groups were compared. The 169 patients had a median virus negative conversion time of 18 days (interquartile range (IQR): 11~25) from symptom onset. Compared with the patients with short-term negative conversion, those with long-term conversion had an older age, higher incidence of comorbidities, chief complaints of cough and chest distress/breath shortness, and severer illness on admission, higher level of leukocytes, neutrophils, aspartate aminotransferase, creatine kinase, and erythrocyte sedimentation rate, lower level of CD3+CD4+ lymphocytes and albumin, and more likely to receive mechanical ventilation. In multivariate analysis, cough, leukocytes, neutrophils and erythrocyte sedimentation rate (ESR) were positively correlated with delayed virus negative conversion, and CD3+CD4+ lymphocytes were negatively correlated. The integrated indicator of leukocytes, neutrophils and CD3+CD4+ lymphocytes showed a good performance in predicting the negative conversion within 2 weeks (area under ROC curve (AUC)=0.815), 3 weeks (AUC=0.804), 4 weeks (AUC=0.812) and 5 weeks (AUC=0.786). In conclusion, longer quarantine periods might be more justified for COVID-19 patients with cough, higher levels of leukocytes, neutrophils and ESR and lower levels of CD3+CD4+ lymphocytes.