AUTHOR=Qiao Xi-Min , Xu Xiao-Feng , Zi Hao , Liu Guo-Xiong , Li Bing-Hui , Du Xiang , Tian Zhi-Hai , Liu Xiao-Ying , Luo Li-Sha , Wang Xiao 

TITLE=Re-positive Cases of Nucleic Acid Tests in Discharged Patients With COVID-19: A Follow-Up Study

JOURNAL=Frontiers in Medicine

VOLUME=Volume 7 - 2020

YEAR=2020

URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2020.00349

DOI=10.3389/fmed.2020.00349

ISSN=2296-858X

ABSTRACT=Background: The frequent emergence of the re-positive patients with COVID-19 has been a potential threaten worldwide. This study aimed to describe data from admission to follow-up for patients with COVID-19, and analyze the possible causes for re-positive nucleic acid test, to provide more scientific basis for reducing the numbers of re-positive patients after discharge. 
Methods: We retrospectively recorded 15 patients with COVID-19 admitted to the Central Hospital of Xianyang, China. The baseline, exposure histories, clinical syndromes, laboratory characteristics, nucleic acid and follow-up tests were analyzed, and the radiological characteristics of re-positive patient at different periods were compared.
Results: 8 (53.33%) patients had the history of travel to Wuhan, 4 (26.67%) patients had close contact with confirmed patients, and 1 (6.67%) patient had close contact with suspected patients. After treatment, all patients had two consecutively negative nucleic acid and were discharged from hospital. All patients were followed-up for more than 14 days, and the average time from discharge to the first follow-up was 14.67±3.31 days (from 9 to 22 days). Most patients showed no clinical symptom and negative nucleic acid, while one patient felt itchy throat and her CT scan showed a light density shadow in the right lower lobe of the lung, and the nucleic acid turned positive again. The second follow-up of the other 14 patients (except the re-positive one) was conducted 20.80±7.78 days (from 13 to 30 days) after discharge, and all of them had negative nucleic acid. The positive patient was immediately readmitted and received a new round of treatment. Her family members and colleagues remained healthy until now.
Conclusions: The quality of nucleic acid testing reagents should be enhanced, and the training of nucleic acid sampling operators should be strengthened to reduce the false-negative results in the nucleic acid of SARS-CoV-2; the clinical specimens of throat and nasopharynx swabs can be collected at the same time; IgM- and IgG-specific antibodies of SARS-CoV-2 should be carried out for discharged patients; the radiological characteristics should be evaluated strictly; the discharge standard can be specified according to the baseline, severity of disease of patients.