Assessment of IgM/IgG Antibody Detection in Comparison with RT-PCR Technique for Diagnostic Purposes in Patients with COVID-19

Background and Aim: The diagnosis of COVID-19 is an essential step toward controlling the pandemic. For this purpose, a series of laboratory methods have been developed. This study evaluated the efficiency of the ELISA method for COVID-19 IgM and IgG detection. Materials and Methods: In this case-control study, 46 blood samples from PCR positive COVID-19 patients and 49 samples from PCR negative COVID-19 subjects were collected. Subsequently, the presence of IgM and IgG in all blood samples was assessed using the Pishtaz Teb ELISA kit. Results: The data demonstrated that among 49 PCR negative, 40 (81.6%) were IgM negative and 9 (19.1%) were IgM positive. Besides, out of the 49 PCR-negative patients, 42 (85.7%) and 7 (14.3%) were IgG negative and positive, respectively. In 46 PCR-positive individuals, 40 (87%) were IgM negative, while 6 (13 %) were IgM positive. Of the 46 PCR-positive patients, 24 (52.2%) were IgG negative, and 22(47.8%) were IgG positive. Conclusion: Our results showed that detection of SARS-CoV-2 IgG and IgM using Pishtaz Teb ELISA kit is not enough for COVID diagnosis, but it can serve as a diagnostic RNA supplement to confirm infection with SARS-CoV-2 in approved clinics and other scientific communities, owing to its easy, rapid, and inexpensive availability.