Evaluation of rapid diagnosis of novel coronavirus disease (COVID-19) using loop-mediated isothermal amplification

Yutaro Kitagawa; Yuta Orihara; Rieko Kawamura; Kazuo Imai; Jun Sakai; Norihito Tarumoto; Masaru Matsuoka; Shinichi Takeuchi; Shigefumi Maesaki; Takuya Maeda

doi:10.1016/j.jcv.2020.104446

Evaluation of rapid diagnosis of novel coronavirus disease (COVID-19) using loop-mediated isothermal amplification

J Clin Virol. 2020 Aug:129:104446. doi: 10.1016/j.jcv.2020.104446. Epub 2020 May 21.

Authors

Affiliations

¹ Department of Clinical Laboratory, Saitama Medical University Hospital, Saitama, Japan.
² Department of Infectious Disease and Infection Control, Saitama Medical University, Saitama, Japan.
³ Department of Clinical Laboratory, Saitama Medical University Hospital, Saitama, Japan; Department of Laboratory Medicine, Saitama Medical University, Saitama, Japan. Electronic address: t_maeda@saitama-med.ac.jp.

Abstract

With the rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there is an urgent need for more rapid and simple detection technologies at the forefront of medical care worldwide. In this study, we evaluated the effectiveness of the Loopamp® 2019-SARSCoV-2 Detection Reagent Kit, which uses loop-mediated isothermal amplification (LAMP) technology. In this protocol, cDNA is synthesized from SARS-CoV-2 RNA using reverse transcriptase, followed by DNA amplification under isothermal conditions in one step. The RT-LAMP test kit amplified the targeted RNA of a SARS-CoV-2 isolate with a detection limit of 1.0 × 101 copies/μL, which was comparable to the detection sensitivity of quantitative reverse transcription PCR (RT-qPCR). Comparison with the results of RT-qPCR for 76 nasopharyngeal swab samples from patients with suspected COVID-19 showed a sensitivity of 100 % and a specificity of 97.6 %. In the 24 RNA specimens derived from febrile Japanese patients with or without influenza A, no amplification was observed using RT-LAMP. RT-LAMP could be a simple and easy-to-use diagnostic tool for the detection of SARS-CoV-2.

Keywords: COVID-19; LAMP; RT-qPCR; SARS-CoV-2.

Publication types

Evaluation Study

MeSH terms

Betacoronavirus / genetics
Betacoronavirus / isolation & purification*
COVID-19
COVID-19 Testing
Clinical Laboratory Techniques / methods*
Coronavirus Infections / diagnosis*
Humans
Japan
Molecular Diagnostic Techniques / methods*
Nucleic Acid Amplification Techniques / methods*
Pandemics
Pneumonia, Viral / diagnosis*
SARS-CoV-2
Sensitivity and Specificity
Time Factors

Supplementary concepts

LAMP assay