Viral Research and Diagnostic Laboratory, Agartala Government Medical College, Agartala, Tripura, India.
Culture and DST Laboratory, Agartala Government Medical College, Agartala, Tripura, India.
Indian J Med Microbiol. 2023 Mar-Apr;42:12-16. doi: 10.1016/j.ijmmb.2022.12.016. Epub 2023 Jan 19.
Real time reverse transcriptase polymerase chain reaction (RT-qPCR) is still considered a gold standard for the diagnosis of COVID-19. However, due to several limitations, use of RT-qPCR is limited in a resource poor setting like North East India. Rapid antigen detection testing kit has revolutionized the diagnosis and management of COVID-19 in India. However, conflicting reports exist regarding the efficacy of the kits for diagnosis of COVID-19. This study aims to highlight the performance of Standard Q COVID-19® Antigen detection kit (SD Biosensor) compared with RT-qPCR in the setup of North East India.
Nasopharyngeal and oropharyngeal swab samples were collected from consenting patients attending the flu clinic in the period from 1st July to December 31, 2020. Samples were transferred to Viral Research and Diagnostic Laboratory (VRDL) for RT-qPCR test. Antigen detection from the patient samples were undertaken using Standard Q ® COVID-19 antigen detection kit (SD Biosensor, Republic of Korea). Data were then analyzed for comparison between RT-qPCR and antigen kit results.
During the study period, 189 samples were collected, out of which 119 were positive by RT-qPCR. Out of 119 positive samples, calculated sensitivity and specificity of the rapid antigen kit was 63% and 100% respectively. Sensitivity and diagnostic accuracy increases in symptomatic patients as compared to asymptomatic patients. Cohen's Kappa coefficient showed a moderate association (0.6) between the kit and RT-qPCR test. The kit performed optimally at a CT value of ≤32.5 for N gene with a predicted sensitivity of 77.3% and specificity of 93.3%.
The study shows an overall acceptable sensitivity and specificity of the testing kit, with a better performance in symptomatic patients. The association of the kit result is moderate with the results obtained in RT-qPCR. In this study, the rapid antigen test kit performed optimally at N gene qRT PCR cut off value of ≤32.5.
实时逆转录聚合酶链反应（RT-qPCR）仍然被认为是 COVID-19 诊断的金标准。然而，由于存在多种局限性，在像印度东北部这样资源匮乏的环境中，RT-qPCR 的使用受到限制。快速抗原检测试剂盒彻底改变了 COVID-19 的诊断和管理。然而，关于试剂盒对 COVID-19 诊断的疗效存在相互矛盾的报道。本研究旨在强调在印度东北部，与 RT-qPCR 相比，Standard Q COVID-19®抗原检测试剂盒（SD Biosensor）的性能。
从同意参加流感诊所的患者中采集鼻咽和口咽拭子样本，时间为 2020 年 7 月 1 日至 12 月 31 日。将样本转移到病毒研究和诊断实验室（VRDL）进行 RT-qPCR 检测。使用 Standard Q ®COVID-19 抗原检测试剂盒（SD Biosensor，大韩民国）对患者样本进行抗原检测。然后对 RT-qPCR 和抗原试剂盒结果进行数据分析比较。
在研究期间，共采集了 189 个样本，其中 119 个通过 RT-qPCR 呈阳性。在 119 个阳性样本中，快速抗原试剂盒的计算灵敏度和特异性分别为 63%和 100%。与无症状患者相比，有症状患者的灵敏度和诊断准确性更高。试剂盒和 RT-qPCR 检测之间的 Cohen's Kappa 系数显示出中度相关性（0.6）。试剂盒在 N 基因 CT 值≤32.5 时表现最佳，预测灵敏度为 77.3%，特异性为 93.3%。
该研究表明，该检测试剂盒的总体灵敏度和特异性可接受，在有症状患者中的表现更好。试剂盒结果与 RT-qPCR 结果的相关性为中度。在本研究中，快速抗原检测试剂盒在 N 基因 qRT-PCR 截止值≤32.5 时表现最佳。
