ABSTRACT Background : Several serological tests for SARS-CoV-2 have been developed or use, but most have only been validated on few samples, and none provide medical practitioners with an easy-to-use, self-contained, bedside test with high accuracy. Material and methods : Two-hundred fifty-six sera from 101 patients hospitalized with SARS-CoV-2 infection (positive RT–PCR) and 50 control sera were tested for IgM/IgG using the NG-Test IgM-IgG COVID all-in-one assay. The seroconversion dynamic was assessed by symptom onset and day of RT–PCR diagnosis. Results: Among the SARS-CoV-2 infected patients, positive IgG and/or IgM result was observed for 67.3% of patients (68/101), including 17 (16.8%) already positive at the day of RT–PCR, and 51 (50.5%) with observable seroconversion, and 32.7% (33/101) remained negative as subsequent sampling was not possible (patient discharge or death). The sensitivity increased with the delay between onset of symptoms and sampling, going from 29.1%, 78.2% and 86.5% for the time periods of 0-9-, 10-14- and >14-days after the onset of symptoms, respectively. Cumulative sensitivity, specificity, Positive Predictive Value and Negative Predictive Value were 97.0%, 100%, 100% and 96.2%, respectively 15-days after the onset of symptoms. No difference in seroconversion delay was observed regardless of whether patients received ventilation. Conclusions: The NG-test is a bedside serological assay that could serve as a complementary source of diagnostic information to RT–PCR and chest imaging. It may also be useful to monitor immunological status of medical and non-medical workers during the ongoing pandemic, and the general population after social distancing measures have eased.
【저자키워드】 COVID-19, serology, Diagnosis, diagnostics, Rapid test, Bedside, 【초록키워드】 serological test, SARS-CoV-2, IgG, IgM, pandemic, SARS-COV-2 infection, Ventilation, diagnostic, discharge, COVID, sensitivity, specificity, Seroconversion, Serological assay, IgM/IgG, sera, Patient, death, General population, information, chest imaging, complementary, symptom onset, infected patients, material, high accuracy, positive, MONITOR, negative, RT–PCR, Practitioner, Social distancing measure, immunological, value, tested, subsequent, remained, onset of symptom, onset of symptoms, patients hospitalized, the SARS-CoV-2, 【제목키워드】 serological test, SARS-CoV-2 antibody, Rapid, Determination,