Correlation of chest CT and RT-PCR testing in coronavirus disease 2019 (COVID-19) in Turkey

Abstract

Aim: Chest CT plays an important role in the treatment and diagnosis of COVID-19. It is important to remember that patients with RT-PCR test positive for COVID-19 infection may have normal chest CT. Material and Methods: This study included patients who underwent RT-PCR and chest CT tests, as well as patients with suspected and confirmed COVID-19 positive cases according to the algorithm of the Institute of Science of Ministry of Health in Turkey were included in this study. The patients were divided into two groups as positive and negative according to RT-PCR results. These groups were divided into two subgroups: with CT findings compatible with COVID-19 and without them. When the RT-PCR test was taken as the gold standard, the specificity, sensitivity, PPV, NPV, and accuracy rates of chest CT were investigated in detecting COVID-19 infection. Results: RT-PCR was positive in 192 patients and negative in 418 patients. The chest CT scan was positive in 43% (82/192) of 192 patients whose RT-PCR results were positive. Chest CT scan was positive in 25% (108/418) of 418 patients whose RT-PCR results were negative. In 31% of the patients (190/610), chest CT findings were positive for COVID-19. When RT-PCR results were taken as a reference, accuracy, specificity, and sensitivity values in terms of COVID-19 infection of chest CT were 44% (95% CI, 392/610 patients), 43% (95% CI, 82/192 patients), and 74% (95% CI, 310/418 patients) respectively. Discussion: According to these data, we think that chest CT is not very successful in detecting patients infected with COVID-19, contrary to the literature. Clinicians should always be careful to identify patients with COVID-19 infection with normal thorax CT or negative RT-PCR testing.