Clinical Performance of the Loop-Mediated Isothermal Amplification Method Compared With Reverse Transcriptase Polymerase Chain Reaction for COVID-19 Diagnosis in Indonesia and the Philippines

Real-time reverse transcriptase polymerase chain reaction (RT-PCR) is considered the gold standard for the diagnosis of coronavirus disease 2019 (COVID-19); however, this method is expensive, time-consuming, and requires skilled personnel. Therefore, this study aimed to evaluate the clinical performance of loop-mediated isothermal amplification (LAMP), a simpler test method. A multinational prospective clinical performance study was conducted in Indonesia and the Philippines, comparing the LAMP method to RT-PCR for the diagnosis of COVID-19. In total, 256 subjects with COVID-19 symptoms underwent RT-PCR testing, of whom 130 and 126 were positive and negative, respectively. In Indonesia (n = 180), 115 (63.9%) tested positive by RT-PCR and 65 (36.1%) tested negative; in the Philippines (n = 76), 15 subjects (19.7%) tested positive by RT-PCR and 61 (80.3%) tested negative. The LAMP and RT-PCR results were concordant in 243/256 subjects (94.9%; 95% confidence interval, 91.5-97.3) (92.8% in Indonesia, 100% in the Philippines). Among 130 RT-PCR-positive subjects, 117 were also positive by LAMP, yielding a sensitivity of 90%. Of the 126 RT-PCR-negative subjects, 126 were also negative by LAMP, yielding a specificity of 100%. The positive and negative predictive values were 100% and 90.6%, respectively. Our study demonstrated high overall accuracy between the LAMP and RT-PCR methods, suggesting the potential utility of the LAMP method for detecting COVID-19 and highlighting its usefulness in managing cases.