tetano
Editor, Senior Moderator
J Clin Virol. 2020 Apr 30;128:104393. doi: 10.1016/j.jcv.2020.104393. [Epub ahead of print]
Clinical evaluation of an immunochromatographic IgM/IgG antibody assay and chest computed tomography for the diagnosis of COVID-19.
Imai K[SUP]1[/SUP], Tabata S[SUP]2[/SUP], Ikeda M[SUP]2[/SUP], Noguchi S[SUP]3[/SUP], Kitagawa Y[SUP]3[/SUP], Matuoka M[SUP]3[/SUP], Miyoshi K[SUP]2[/SUP], Tarumoto N[SUP]4[/SUP], Sakai J[SUP]4[/SUP], Ito T[SUP]2[/SUP], Maesaki S[SUP]4[/SUP], Tamura K[SUP]2[/SUP], Maeda T[SUP]5[/SUP].
Author information
Abstract
BACKGROUND:
We evaluated the clinical performance of an immunochromatographic (IC) IgM/IgG antibody assay for severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) and chest computed tomography (CT) for the diagnosis of Coronavirus disease 2019 (COVID-19).
METHODS:
We examined 139 serum specimens collected from 112 patients with COVID-19 and 48 serum specimens collected from 48 non-COVID-19 patients. The presence of IgM/IgG antibody for SARS-COV2 was determined using the One Step Novel Coronavirus (COVID-19) IgM/IgG Antibody Test. Chest CT was performed in COVID-19 patients on admission.
FINDINGS:
Of the139 COVID-19 serum specimens, IgM was detected in 27.8 %, 48.0 %, and 95.8 % of the specimens collected within 1 week, 1-2 weeks, and >2 weeks after symptom onset and IgG was detected in 3.3 %, 8.0 %, and 62.5 %, respectively. Among the 48 non-COVID-19 serum specimens, 1 generated a false-positive result for IgM. Thirty-eight of the 112 COVID-19 patients were asymptomatic, of whom 15 were positive for IgM, and 74 were symptomatic, of whom 22 were positive for IgM and 7 were positive for IgG. The diagnostic sensitivity of CT scan alone and in combination with the IC assay was 57.9 % (22/38) and 68.4 % (26/38) for the asymptomatic patients and 74.3 % (55/74) and 82.4 % (61/74) for the symptomatic patients, respectively.
CONCLUSION:
The IC assay had low sensitivity during the early phase of infection, and thus IC assay alone is not recommended for initial diagnostic testing for COVID-19. If RT-qPCR is not available, the combination of chest CT and IC assay may be useful for diagnosing COVID-19.
Copyright ? 2020 Elsevier B.V. All rights reserved.
KEYWORDS:
COVID-19; Chest CT scan; Immunochromatographic assay; SARS-CoV-2
PMID:32387968DOI:10.1016/j.jcv.2020.104393
Clinical evaluation of an immunochromatographic IgM/IgG antibody assay and chest computed tomography for the diagnosis of COVID-19.
Imai K[SUP]1[/SUP], Tabata S[SUP]2[/SUP], Ikeda M[SUP]2[/SUP], Noguchi S[SUP]3[/SUP], Kitagawa Y[SUP]3[/SUP], Matuoka M[SUP]3[/SUP], Miyoshi K[SUP]2[/SUP], Tarumoto N[SUP]4[/SUP], Sakai J[SUP]4[/SUP], Ito T[SUP]2[/SUP], Maesaki S[SUP]4[/SUP], Tamura K[SUP]2[/SUP], Maeda T[SUP]5[/SUP].
Author information
Abstract
BACKGROUND:
We evaluated the clinical performance of an immunochromatographic (IC) IgM/IgG antibody assay for severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) and chest computed tomography (CT) for the diagnosis of Coronavirus disease 2019 (COVID-19).
METHODS:
We examined 139 serum specimens collected from 112 patients with COVID-19 and 48 serum specimens collected from 48 non-COVID-19 patients. The presence of IgM/IgG antibody for SARS-COV2 was determined using the One Step Novel Coronavirus (COVID-19) IgM/IgG Antibody Test. Chest CT was performed in COVID-19 patients on admission.
FINDINGS:
Of the139 COVID-19 serum specimens, IgM was detected in 27.8 %, 48.0 %, and 95.8 % of the specimens collected within 1 week, 1-2 weeks, and >2 weeks after symptom onset and IgG was detected in 3.3 %, 8.0 %, and 62.5 %, respectively. Among the 48 non-COVID-19 serum specimens, 1 generated a false-positive result for IgM. Thirty-eight of the 112 COVID-19 patients were asymptomatic, of whom 15 were positive for IgM, and 74 were symptomatic, of whom 22 were positive for IgM and 7 were positive for IgG. The diagnostic sensitivity of CT scan alone and in combination with the IC assay was 57.9 % (22/38) and 68.4 % (26/38) for the asymptomatic patients and 74.3 % (55/74) and 82.4 % (61/74) for the symptomatic patients, respectively.
CONCLUSION:
The IC assay had low sensitivity during the early phase of infection, and thus IC assay alone is not recommended for initial diagnostic testing for COVID-19. If RT-qPCR is not available, the combination of chest CT and IC assay may be useful for diagnosing COVID-19.
Copyright ? 2020 Elsevier B.V. All rights reserved.
KEYWORDS:
COVID-19; Chest CT scan; Immunochromatographic assay; SARS-CoV-2
PMID:32387968DOI:10.1016/j.jcv.2020.104393