Purpose. To determine computed tomography diagnostic criteria for early identification of bacterial infection complicating SARS-CoV-2 viral pneumonia, to provide detection and timely treat the secondary bacterial lung complications in patients with COVID-19 infection.

Materials and methods. This study was designed as a retrospective cohort clinical trial. The total of 58 patients was enrolled. All of them had received medical treatment in Pirogov National Medical and Surgical Center, Moscow from 01.03.2020 to 15.06.2020 due to the SARS-CoV-2 infection. The cohort was subdivided into two groups that included 26 and 32 patients, respectively. In the first group (n = 26) was made based on clinical course of the disease and laboratory findings, the secondary bacterial infection on top of the preexisting viral lesions was detect and treated. The patients that showed no clinical or laboratory signs of secondary infection (n = 32) were included in the second control group. All of the radiographic (CT) findings in both groups were listed and subsequently thoroughly analyzed by means of statistics.

Results. The most informative CT features of associated secondary bacterial pneumonia in our study were: areas of consolidation corresponding to the segmental structure of the lungs; the border of consolidation, mostly following the interlobar pleura; consolidation that occurs during the last 5-7 days in the area with unchanged parenchyma on initial scan. It was also noted specific subtype of air bronchogram, which included easily traceable bronchi from central areas to periphery.

Conclusion. Computed tomography can be efficiently used with clinical and laboratory criteria to determine the secondary bacterial infection complicating SARS-CoV-2 viral pneumonia.