BACKGROUND:The 2019 coronavirus disease outbreak (COVID-19) quickly swept the world in just a month. Polymerase chain reaction (PCR) is used in the diagnosis of this disease, but this test has limitations related to false negative results, as well as PCR is a time-consuming procedure. Under these conditions, chest computed tomography (CT) can become one of the main methods in the Clinicians Arsenal used for early detection of COVID-19 in patients who first seek medical help.
AIMS:comparison of the frequency of community-acquired pneumonia and its characteristics according to CT data before and during the COVID-19 epidemic and study of the possibilities of their timely detection and differential diagnosis.
MATERIALS AND METHODS:A retrospective analysis of chest CT scans results was performed in Davydovsky hospital (Moscow) from April 1 to April 17, 2020. It included all patients diagnosed with viral pneumonia at the CT. All patients with suspected diagnosis of viral pneumonia underwent PCR testing. Retrospective analysis of chest CT data from patients admitted to the hospital with suspected pneumonia for the same period in 2019 was taken as a comparison group.
RESULTS:For the period from April 1 to April 17, 2020 according to chest CT, pneumonia was diagnosed in 140 cases, of which 65 (46.4%) were described as viral, compared with the same period in 2019 7 diagnoses of viral pneumonia (10.3%) were described a significant increase in cases of viral pneumonia (5.723;p0.01). Results of PCR test in patients with viral pneumonia according to CT data was: positive in 34 (52.3%), negative in 22 (33.8%), 9 (13.9%) patients were not tested. When comparing the frequency of detection on CT of viral pneumonia patterns in patients for the same period of time in 2019 and 2020, no significant differences were found. The probability of COVID-19 due to results of chest CT was: average 13.8%, high 75.4%. The severity of viral pneumonia according to CT data was: light 38.5%, medium 46.2%, severe 12.3%, extremely severe 3.1%.
CONCLUSIONS:Rapid CT diagnostics of COVID-19, even with false negative results of PCR tests, can help to isolate a patient with suspected COVID-19, start treatment on time and prevent the further spread of viral infection in a pandemic. Nevertheless, due to the non-specificity of the revealed picture, the possibilities of CT to identify lung lesions by specific viral agents are limited.