Clinical Usefulness of the Loop-Mediated Isothermal Amplification Assay for SARS-CoV-2 Detection.

BACKGROUND

Loop-mediated isothermal amplification (LAMP) is a molecular diagnostic method known for its rapid processing and operational simplicity due to its isothermal amplification process. While LAMP has demonstrated comparable diagnostic accuracy to PCR in certain applications, its performance may vary depending on assay design and implementation. This study aimed to evaluate the diagnostic performance of the MmaxSure™ assay (MmaxSure™; Mmonitor, Daegu, South Korea) in detecting SARS-CoV-2, comparing it with the STANDARD™ M nCoV Real-Time Detection Kit (STANDARD; SD BioSensor, Suwon, South Korea) using nasopharyngeal and oropharyngeal swab specimens.

METHODS

A total of 333 specimens were included in the analysis, consisting of 113 positive and 220 negative nasopharyngeal and oropharyngeal swab samples. All specimens were tested using the MmaxSure™ assay, and the results were compared to those obtained using the STANDARD™ M nCoV Real-Time Detection Kit. The diagnostic performance of the MmaxSure™ assay was evaluated in terms of positive percent agreement (PPA), negative percent agreement (NPA), and Cohen's kappa index for inter-assay agreement. Sensitivity, specificity, and limit of detection (LOD) for SARS-CoV-2 variants were also determined.

RESULTS

The MmaxSure™ assay demonstrated a 100% PPA and a 100% NPA with the STANDARD™ M nCoV Real-Time Detection Kit. The Cohen's kappa index was 1.0, indicating perfect agreement between the two diagnostic methods. The MmaxSure™ assay exhibited a high sensitivity, detecting SARS-CoV-2 variants at a LOD of 2 - 4 copies/µL, without cross-reactivity with other pathogens.

CONCLUSIONS

The MmaxSure™ Fast SARS-CoV-2 Detection Kit, based on LAMP technology, exhibited a high level of diagnostic accuracy in detecting SARS-CoV-2. Its rapid turnaround time and minimal equipment requirements suggest its potential suitability for point-of-care applications. However, further prospective studies with a broader range of clinical specimens and real-world validation are needed to confirm its diagnostic utility across diverse settings.