Correlation of clinical, laboratory, and short-term outcomes of immunocompromised and immunocompetent COVID-19 patients with semi-quantitative chest CT score findings: A case-control study

BACKGROUND

As the effects of immunosuppression are not still clear on COVID-19 patients, we conducted this study to identify clinical and laboratory findings associated with pulmonary involvement in both immunocompromised and immunocompetent patients.

METHODS

A case-control of 107 immunocompromised and 107 immunocompetent COVID-19 patients matched for age and sex with either positive RT-PCR or clinical-radiological findings suggestive of COVID-19 enrolled in the study. Their initial clinical features, laboratory findings, chest CT scans, and short-term outcomes (hospitalization time and intensive care unit [ICU] admission) were recorded. In addition, pulmonary involvement was assessed with the semi-quantitative scoring system (0-25).

RESULTS

Pulmonary involvement was significantly lower in immunocompromised patients in contrast to immunocompetent patients, especially in RLL (p = 0.001), LUL (p = 0.023), and both central and peripheral (p = 0.002), and peribronchovascular (p = 0.004) sites of lungs. Patchy (p < 0.001), wedged (p = 0.002), confluent (p = 0.002) lesions, and ground glass with consolidation pattern (p < 0.001) were significantly higher among immunocompetent patients. Initial signs and symptoms of immunocompromised patients including dyspnea (p = 0.008) and hemoptysis (p = 0.036), respiratory rate of over 25 (p < 0.001), and spo2 of below 93% (p = 0.01) were associated with higher pulmonary involvement. Total chest CT score was also associated with longer hospitalization (p = 0.016) and ICU admission (p = 0.04) among immunocompromised patients.

CONCLUSIONS

Pulmonary involvement score was not significantly different among immunocompromised and immunocompetent patients. Initial clinical findings (dyspnea, hemoptysis, higher RR, and lower Spo2) of immunocompromised patients could better predict pulmonary involvement than laboratory findings.

Association between lung opacities and visceral fat in COVID-19 patients

Purpose

To assess the relationship between the amount of the epigastric visceral fat area and the severity of pneumonia in the course of COVID-19 using chest computed tomography (CT) examinations.

Material and methods

177 patients (54 female), with COVID-19 infection were included. A routine chest CT was performed to assess the severity of pneumonia. The affected lung tissue as well as semi-quantitative scales such as the Chest CT Score and Total Opacity Score were calculated using SyngoVia VB30A CT Pneumonia Analysis software. The epigastric region area of visceral fat (L1) was also determined.

Results

The mean value of the visceral adipose tissue area was 196.23 ± 101.36 cm². The area of adipose tissue significantly correlated with the percentage of the affected lung tissue (r = 0.1476; p = 0.050), the Chest CT Score (r = 0.2086; p = 0.005), and the Total Opacity Score (r = 0.1744; p = 0.200). The mean area of adipose tissue in the age group ≥ 65 years was 216.13 ± 105.19 cm², while in the group < 65 years, it was 169.18 ± 89.69 cm². This difference was statistically significant (p = 0.002).

Conclusions

The study showed a relationship between the area of visceral adipose tissue and the degree of lung inflammation in COVID-19 disease in patients under 65 years of age.

Longitudinal Chest CT Features in Severe/Critical COVID-19 Cases and the Predictive Value of the Initial CT for Mortality

Purpose

To evaluate longitudinal computed tomography (CT) features and the predictive value of the initial CT and clinical characteristics for mortality in patients with severe/critical coronavirus disease 2019 (COVID-19) pneumonia.

Methods

A retrospective analysis was performed on patients with COVID-19 pneumonia confirmed by laboratory. By excluding mild and common patients, 155 severe/critical patients with definite outcome were finally enrolled. A total of 516 CTs of 147 patients were divided into four stages according to the time after onset (stage 1, 1–7 days; stage 2, 8–14 days; stage 3, 15–21 days, and stage 4, >21 days). The evolving imaging features between the survival and non-survival groups were compared by using Chi-square, Fisher’s exact test, student’s t-test or Mann–Whitney U-test, as appropriate. The predictive value of clinical and CT features at admission for mortality was analysed through logistic regression analysis. To avoid overfitting caused by CT scores, CT scores were divided into two parts, which were combined with clinical variables, respectively, to construct the models.

Results

Ground-glass opacities (GGO) patterns were predominant for stages 1 and 2 for both groups (both P>0.05). The numbers of consolidation lesions increased in stage 3 in both groups (P=0.857), whereas the linear opacity increased in the survival group but decreased in the non-survival group (P=0.0049). In stage 4, the survival group predominantly presented linear opacity patterns, whereas the non-survival group mainly showed consolidation patterns (P=0.007). Clinical and imaging characteristics correlated with mortality; multivariate analyses revealed age >71 years, neutrophil count >6.38 × 10⁹/L, aspartate aminotransferase (AST) >58 IU/L, and CT score (total lesions score >17 in model 1, GGO score >14 and consolidation score >2 in model 2) as independent risk factors (all P<0.05). The areas under the curve of the six independent risk factors alone ranged from 0.65 to 0.75 and were 0.87 for model 2, 0.89 for model 1, and 0.92 for the six variables combined. Statistical differences were observed between Kaplan Meier curves of groups separated by cut-off values of these six variables (all P<0.01).

Conclusion

Longitudinal imaging features demonstrated differences between the two groups, which may help determine the patient’s prognosis. The initial CT score combined with age, AST, and neutrophil count is an excellent predictor for mortality in COVID-19 patients.