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Published on: December 19, 2020
Risk factors for delayed negative conversion of SARS-CoV-2 in patients with COVID-19 pneumonia: a retrospective
Pingzheng Mo1, Liping Deng1, Xiaoping Liu2
1Department of Infectious Diseases, Zhongnan Hospital of Wuhan University, Wuhan430071, Hubei, China.
Insights
Identifying risk factors for delayed SARS-CoV-2 negative conversion in COVID-19 patients is crucial. Cough, elevated leucocytes, neutrophils, and ESR, along with low CD3+CD4+ lymphocytes, predict longer viral shedding, informing quarantine duration.
Area of Science:
- Infectious Diseases
- Virology
- Clinical Medicine
Background:
- The COVID-19 pandemic caused by SARS-CoV-2 has led to significant global health challenges.
- Understanding factors influencing viral clearance is essential for patient management and public health strategies.
Purpose of the Study:
- To identify clinical and laboratory risk factors associated with delayed SARS-CoV-2 negative conversion in COVID-19 patients.
- To evaluate the predictive performance of identified factors for prolonged viral shedding.
Main Methods:
- Retrospective single-centre study of 169 COVID-19 patients.
- Patients grouped based on median SARS-CoV-2 negative conversion time (18 days).
- Comparison of clinical characteristics, comorbidities, and laboratory markers between short-term and long-term conversion groups; multivariate analysis performed.
Main Results:
- Long-term converters were older, had more comorbidities, presented with cough and chest distress, and exhibited severe illness.
- Elevated leucocytes, neutrophils, aspartate aminotransferase, creatine kinase, and erythrocyte sedimentation rate (ESR) were observed in long-term converters.
- Lower CD3+CD4+ lymphocytes and albumin levels, along with a higher likelihood of mechanical ventilation, were noted in long-term converters.
- Multivariate analysis identified cough, leucocytes, neutrophils, ESR (positive correlation), and CD3+CD4+ lymphocytes (negative correlation) as predictors of delayed conversion.
- An integrated indicator of leucocytes, neutrophils, and CD3+CD4+ lymphocytes demonstrated good predictive performance (AUC 0.786-0.815).
Conclusions:
- COVID-19 patients with cough, elevated leucocytes, neutrophils, ESR, and low CD3+CD4+ lymphocytes may require longer quarantine periods.
- These factors can help predict delayed SARS-CoV-2 RNA negativity.
- The findings support individualized quarantine strategies based on specific patient risk factors.
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-centre study, we included 169 consecutive patients with confirmed COVID-19 in Zhongnan Hospital of Wuhan University from 15th January to 2nd March. The cases were divided into two groups according to the median time of SARS-CoV-2 negative conversion. The differences between groups were compared. In total, 169 patients had a median virus negative conversion time of 18 days (interquartile range: 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 leucocytes, neutrophils, aspartate aminotransferase, creatine kinase and erythrocyte sedimentation rate (ESR), lower level of CD3+CD4+ lymphocytes and albumin and more likely to receive mechanical ventilation. In multivariate analysis, cough, leucocytes, neutrophils and ESR were positively correlated with delayed virus negative conversion, and CD3+CD4+ lymphocytes were negatively correlated. The integrated indicator of leucocytes, 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 leucocytes, neutrophils and ESR and lower levels of CD3+CD4+ lymphocytes.
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