Community-Acquired Pneumonia Associated with COVID-19: Diagnostic Significance of Imaging Methods (CT, LUS) and Comparative Characteristics of CT- and LUS-Patterns

Abstract

Objective — to determine the imaging changes in community-acquired pneumonia in different severity of COVID-19; to define the diagnostic significance of CT, LUS, establish the correspondence of CT- and LUS-patterns. Materials and methods. We examined 22 patients (pts) (men — 11 (50.0 %), women — 11 (50.0 %), mean age — 67.0 (54.0; 74.0) years) with COVID-19 pneumonia. Clinical examination — general investigation, assessment of dyspnea severity (mMRC), pulse oximetry. The spread of lung lesions was determined by CT and LUS. Changes were described as CT- and LUS-patterns. Non-parametric. Results and discussion. In severe COVID-19 cases (end of the 1st week of illness), the extent of lung lesions aligned with CT-1, revealing bilateral subpleural «ground glass» opacities. Bilateral changes were observed in lung ultrasound (LUS), with a Lung Ultrasound Score (LUSS) of 2—4 points. The CT pattern of «ground glass» corresponded to LUS patterns indicating mild to moderate interstitial changes (IC).By the 2nd and 3rd weeks, the area of lung lesions corresponded to CT-1 and 2, and the CT pattern of «ground glass» became diffuse and bilateral. Bilateral LUS changes were noted, with LUSS ranging from 4 to 18 points. The CT pattern of «ground glass» aligned with LUS patterns indicating mild to moderate IC, pleural thickening, and the absence of A-lines. The CT pattern of consolidation corresponded to a similar LUS pattern.In patients with a critical course during the 2nd and 3rd weeks, the lesion area extended to 60–90 %. Bilateral LUS changes persisted, with LUSS ranging from 16 to 22 points. There was a significant correlation between the area of lung lesions observed on CT and LUS (p < 0.0001). Conclusions. In the 1st week of illness, verification of severe COVID-19 should be grounded in the presence of severe dyspnea and decreased saturation. During the 2nd and 3rd weeks, verification can be based on decreased saturation and the extent of lung lesions as assessed by CT and lung ultrasound (LUS). In critical patients, the area of lung lesions ranged from 60 to 90 % on CT and/or exceeded 15 points on the LUSS. The CT pattern of «ground glass» corresponded to interstitial changes (IC), pleural thickening, and the absence of A-lines on LUS. Similarly, the CT pattern of consolidation corresponded to a consolidation pattern on LUS.