Systematic review and meta-analysis of the CT imaging characteristics of infectious pneumonia.

BACKGROUND: Since December 2019, there have been cases of infectious pneumonia of unknown cause in Wuhan, Hubei Province, China. On January 12, 2020, the World Health Organization (WHO) named it COVID-19. There are few studies on the clinical characteristics of patients with COVID-19, and results vary widely in sample sizes. METHODS: Chinese and English databases were searched with "Infectious pneumonia", "COVID-19", "CT", "SARS-COV-2", and "Diagnose" as keywords. Rev Man 5.3 software provided by the Cochrane system was used to assess the quality of the included literature. RESULTS: Of the 18 included studies, ground-glass shadow was the most common computed tomography (CT) sign [95% confidence interval (CI): 0.79-0.97], followed by thickening of the blood vessels (95% CI: 0.63-0.78), and pleural thickening (95% CI: 0.02-0.15). Of the 18 studies, 12 reported that the lesions were externally subpleural (95% CI: 0.132-0.173), and 6 reported that the lesions were distributed in a single lobe (95% CI: 0.598-0.841). The heterogeneity test results showed that the morphology of the lesions was cord-like (95% CI: 0.092-0.172), grid-like (95% CI: 0.152-0.193), patchy (95% CI: 0.192-0.313), and nodular (95% CI: 0.591-0.745). DISCUSSION: Ground-glass opacity was a typical CT manifestation for patients with infectious pneumonia, and CT signs were instrumental in diagnosing this disease.

Correlation between ground-glass opacity on pulmonary CT and the levels of inflammatory cytokines in patients with moderate-to-severe COVID-19 pneumonia.

Objectives: Comparative analysis of laboratory data in moderate-to-severe COVID-19 patients presenting with or without ground-glass opacities (GGOs). Methods: This retrospective study examined 61 patients with moderate-to-severe COVID-19, as defined by the report of the WHO-China Joint Mission on COVID-19. All patients were admitted to the Department of Infectious Diseases, Wuhan Union Hospital from Dec 28, 2019 to Feb 22, 2020 and classified into a GGO group or a non-GGO group based on CT results. The clinical characteristics and laboratory data of the two groups were compared. Data were analyzed using univariate and multivariate analysis, and using receiver operating characteristic (ROC) analysis. Results: Forty-five patients were in the GGO group (73.8%, 21 females, 24 males, mean age 54.8±17.8 years) and 16 were in the non-GGO group (26.2%, 11 females, 5 males, mean age 53±14.9 years). The levels of IL-2, IL-4, and IFN-γ were greater in the GGO group (all P<0.05). ROC analysis indicated that an elevated level of IL-2 was a good predictor of GGO (area under the curve: 0.716, optimal cutoff: 3.205 pg/mL, 53.8% sensitivity, 87.5% specificity, p<0.05). Multivariate analysis showed that IL-2 level was a significant and independent risk factor for lung GGO (OR: 8.167; 95% CI: 1.63, 40.8; P<0.05). Conclusions: There were correlations between GGO in the lungs of patients with moderate-to-severe COVID-19 and the levels of IL-2, IL-4, and INF-γ. IL-2 was a significant and independent risk factor for GGO. These findings provide a basis for studying the mechanism of pulmonary lesions in COVID-19 patients.