Comparison of chest computed tomography findings of RT-PCR negative and RT-PCR positive cases in COVID-19 patients

OBJECTIVE: The purpose was to compare the results of the RT-PCR test, with the findings of Chest CT and to determine the features of CT for the diagnosis of COVID-19 and how to approach RT-PCR negative patients. MATERIAL METHOD: Chest CT findings of 569 COVID-19 diagnosed patients, followed up at the pandemic wards between March and June 2020 were retrospectively examined. Patients were grouped according to RT-PCR results, gender, and age. RESULTS: 284 (49%) were RT-PCR(+), 285 (50.8%) were RT-PCR(−) of total 569 patients. 11 (1.9%) of RT-PCR(+) had no involvement in Chest CT while all the RT-PCR(−) patients were CT(+). The distribution of lesions in CT were; 544 (95.6%) bilateral, 553 (97.2%) multilobar, 557(98%) peripherally 151 (26.5%) posteriorly localized. The most common findings were; 539 (94.7%) ground-glass opacity (GGO), 365 (64.1%) consolidation, 160 (28.1%) crazy paving interlobular septal thickening. CO-RADS mean value was 5.4 ± 0.7. GGO and reticulation in RT-PCR(−) patients were 280 (98.2%) and 24 (8.4%); while they were 259 (91.2%) and 12 (4.2%) in RT-PCR(+) patients, were significantly higher (p < 0.05). No significant difference was observed, in CT findings for gender. Only the findings of crazy paving interlobular septal thickening and reticulation in 18–64 age group were significantly higher than that in 65–94 age group, 105 (24.8%)–55 (37.9%), 19 (4.5%)–17 (11.7%) respectively (p < 0.05). CONCLUSION: The typical findings of COVID-19 pneumonia in Chest CT are: GGO, consolidation and crazy paving in bilateral, peripheral, posterior localization. CT plays an essential role for diagnosis, isolation and treatment in cases of COVID-19 and RT-PCR negative test should be verified by CT.