The Accuracy of Enzyme-Linked Immunosorbent Assay in the Diagnosis of COVID-19 in Iranian Children

The present study aimed to evaluate the accuracy of enzyme-linked immunosorbent assay (ELISA) compared to the real-time reverse transcription-polymerase chain reaction (rRT-PCR) in the diagnosis of coronavirus disease 2019 (COVID-19) in Iranian children. 

Materials and Methods:

In this cross-sectional study, 90 children under 15 years of age were randomly selected from suspects of COVID-19 referred to the Tabriz Children Hospital, the main pediatric COVID-19 diagnostic center of Tabriz, from May 21, 2020 to June 21, 2020. Blood and nasopharyngeal samples were taken simultaneously at the referring time. The diagnostic accuracy of ELISA-based IgM and IgG antibody tests for COVID-19 were compared with the rRT-PCR.

The calculated sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, overall diagnostic accuracy, and diagnostic odds ratio were 0.5745, 0.9767, 0.9643, 0.6774, 24.66, 0.4357, 0.7667, and 56.60 for IgM; and 0.6170, 0.9302, 0.9355, 0.6897, 8.84, 0.4117, 0.7667, and 21.47 for IgG, respectively.

Due to the lower sensitivity of antibody detection-based serological tests compared to rRT-PCR, they cannot be considered as initial and reliable tests for the diagnosis of COVID-19. It can be suggested that the serological tests be only used as complementary tests to rRT-PCR or for monitoring the immune response of children with COVID-19.