Clinical testing on SARS-CoV-2 swab samples using reverse-transcription loop-mediated isothermal amplification (RT-LAMP)

BMC Infect Dis. 2022 Aug 18;22(1):697. doi: 10.1186/s12879-022-07684-w.

Abstract

Background: High cost of commercial RNA extraction kits limits the testing efficiency of SARS-CoV-2. Here, we developed a simple nucleic acid extraction method for the detection of SARS-CoV-2 directly from nasopharyngeal swab samples.

Methods: A pH sensitive dye was used as the end point detection method. The obvious colour changes between positive and negative reactions eliminates the need of other equipment.

Results: Clinical testing using 260 samples showed 92.7% sensitivity (95% CI 87.3-96.3%) and 93.6% specificity (95% CI 87.3-97.4%) of RT-LAMP.

Conclusions: The simple RNA extraction method minimizes the need for any extensive laboratory set-up. We suggest combining this simple nucleic acid extraction method and RT-LAMP technology as the point-of care diagnostic tool.

Keywords: Diagnosis; Phenol red; RT-LAMP; SARS-CoV-2; pH sensitive indicator.

MeSH terms

  • COVID-19 Testing* / methods
  • COVID-19* / diagnosis
  • COVID-19* / virology
  • Humans
  • Molecular Diagnostic Techniques* / methods
  • Nasopharynx / virology
  • Nucleic Acid Amplification Techniques* / methods
  • Point-of-Care Systems
  • RNA, Viral / analysis
  • RNA, Viral / genetics
  • RNA, Viral / isolation & purification
  • SARS-CoV-2* / genetics
  • SARS-CoV-2* / isolation & purification
  • Sensitivity and Specificity

Substances

  • RNA, Viral

Supplementary concepts

  • LAMP assay