tetano
Editor, Senior Moderator
J Appl Lab Med
. 2020 May 19;jfaa079.
doi: 10.1093/jalm/jfaa079. Online ahead of print.
Longitudinal Monitoring of SARS-CoV-2 IgM and IgG Seropositivity to Detect COVID-19
Raymond T Suhandynata[SUP] 1 [/SUP], Melissa A Hoffman[SUP] 1 [/SUP], Michael J Kelner[SUP] 1 [/SUP], Ronald W McLawhon[SUP] 1 [/SUP], Sharon L Reed[SUP] 1 [/SUP], Robert L Fitzgerald[SUP] 1 [/SUP]
Affiliations
Abstract
Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a novel beta-coronavirus that has recently emerged as the cause of the 2019 coronavirus pandemic (COVID-19). Polymerase chain reaction (PCR) based tests are optimal and recommended for the diagnosis of an acute SARS-CoV-2 infection. Serology tests for viral antibodies provide an important tool to diagnose previous exposure to the virus. Here we evaluate the analytical performance parameters of the Diazyme SARS-CoV-2 IgM/IgG serology assays and describe the kinetics of IgM and IgG seroconversion observed in patients with PCR confirmed COVID-19 who were admitted to our hospital.
Methods: We validated the performance of the Diazyme assay in 235 subjects to determine specificity. Subsequently, we evaluated the SARS-CoV-2 IgM and IgG seroconversion of 54 PCR confirmed COVID-19 patients and determined sensitivity of the assay at three different timeframes.
Result: Sensitivity and specificity for detecting seropositivity at ≥ 15 days following a positive SARS-CoV-2 PCR result, was 100.0% and 98.7% when assaying for the panel of IgM and IgG. The median time to seropositivity observed for a reactive IgM and IgG result from the date of a positive PCR was 5 days (IQR: 2.75-9 days) and 4 days (IQR: 2.75-6.75 days), respectively.
Conclusions: Our data demonstrates that the Diazyme IgM/IgG assays are suited for the purpose of detecting SARS-CoV-2 IgG and IgM in patients with suspected SARS-CoV-2 infections. For the first time, we report longitudinal data showing the evolution of seroconversion for both IgG and IgM in a cohort of acutely ill patients in the United States. We also demonstrate a low false positive rate in patients who were presumed to be disease free.
Keywords: COVID-19; SARS-CoV-2; antibody; diagnosis; serology.
? 2020 American Association for Clinical Chemistry.
. 2020 May 19;jfaa079.
doi: 10.1093/jalm/jfaa079. Online ahead of print.
Longitudinal Monitoring of SARS-CoV-2 IgM and IgG Seropositivity to Detect COVID-19
Raymond T Suhandynata[SUP] 1 [/SUP], Melissa A Hoffman[SUP] 1 [/SUP], Michael J Kelner[SUP] 1 [/SUP], Ronald W McLawhon[SUP] 1 [/SUP], Sharon L Reed[SUP] 1 [/SUP], Robert L Fitzgerald[SUP] 1 [/SUP]
Affiliations
- PMID: 32428207
- DOI: 10.1093/jalm/jfaa079
Abstract
Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a novel beta-coronavirus that has recently emerged as the cause of the 2019 coronavirus pandemic (COVID-19). Polymerase chain reaction (PCR) based tests are optimal and recommended for the diagnosis of an acute SARS-CoV-2 infection. Serology tests for viral antibodies provide an important tool to diagnose previous exposure to the virus. Here we evaluate the analytical performance parameters of the Diazyme SARS-CoV-2 IgM/IgG serology assays and describe the kinetics of IgM and IgG seroconversion observed in patients with PCR confirmed COVID-19 who were admitted to our hospital.
Methods: We validated the performance of the Diazyme assay in 235 subjects to determine specificity. Subsequently, we evaluated the SARS-CoV-2 IgM and IgG seroconversion of 54 PCR confirmed COVID-19 patients and determined sensitivity of the assay at three different timeframes.
Result: Sensitivity and specificity for detecting seropositivity at ≥ 15 days following a positive SARS-CoV-2 PCR result, was 100.0% and 98.7% when assaying for the panel of IgM and IgG. The median time to seropositivity observed for a reactive IgM and IgG result from the date of a positive PCR was 5 days (IQR: 2.75-9 days) and 4 days (IQR: 2.75-6.75 days), respectively.
Conclusions: Our data demonstrates that the Diazyme IgM/IgG assays are suited for the purpose of detecting SARS-CoV-2 IgG and IgM in patients with suspected SARS-CoV-2 infections. For the first time, we report longitudinal data showing the evolution of seroconversion for both IgG and IgM in a cohort of acutely ill patients in the United States. We also demonstrate a low false positive rate in patients who were presumed to be disease free.
Keywords: COVID-19; SARS-CoV-2; antibody; diagnosis; serology.
? 2020 American Association for Clinical Chemistry.