Diagnosis of pediatric COVID-19

Accurate diagnosis of SARS-CoV-2 infection is critical for the management of individuals with suspected COVID-19 diseases, as well as instituting public health measures. The experience gained over two years of the pandemic has led to a better appreciation of the scope and utility of various diagnostic modalities. Laboratory tests to diagnose COVID-19 in human beings can be broadly categorized as direct and indirect tests. In children (as in adults), RT-PCR is the current gold standard for diagnosis. RT-PCR detects footprints of the virus and its variants. However, its sensitivity is still less than desired. Rapid antigen tests are less accurate than RT-PCR, but the quick availability of results helps in outbreak control. Antibody tests can be used for retrospective diagnosis of infection, but currently available tests do not correlate with protection conferred by vaccination. The initial hype around chest computed tomography scans for diagnosis has now settled, and it is no longer considered a primary diagnostic modality. There are nonspecific changes in many hematological and biochemical parameters, which are more useful for monitoring disease progression than diagnosis.