Imaging features
Among 5 studies reporting data on chest CT[15, 21, 22, 25, 27], the incidence of bilateral pneumonia was 95.8% (162 in 219) in Severe group and 73.4% (378 in 515) in Non-severe group. With pooled OR of 1.48 (95%CI: 0.50 to 4.35), it was demonstrate severe Covid-19 patient was associated with slightly increased risk of bilateral pneumonia. But meta-analysis did not reveal any statistical difference (P=0.48). Consistently, with pooled OR of 0.98 for unilateral pneumonia (95%CI: 0.40 to 2.42, P=0.97), 3.71 for ground-glass opacities (95%CI: 0.45 to 30.23, P=0.22), 3.32 for consolidation (95%CI: 1.00 to 11.03, P=0.05) and 8.23 for bronchial wall thickening (95%CI: 0.59 to 115.05, P=0.12), it was demonstrated that unilateral pneumonia[21, 25], ground-glass opacities [15, 21], consolidation[15, 21] and bronchial wall thickening [15, 21] were unrelated to the severity of Covid-19.
However, in 2 trials reporting data on reticulation in CT [15, 21], 12 of 39 patients in Severe group (30.8%) and 40 of 145 in Non-severe group (27.9%) were found to have reticulation in chest CT. With pooled OR of 2.86 (95%CI: 1.01 to 8.14, P<0.05), it was demonstrated that patients with reticulation in CT were more likely to progress into severe Covid-19.
In 2 trials reporting data on intrathoracic lymph node enlargement [15, 21], 8 of 39 patients in Severe group (20.5%) and 0 of 145 in Non-severe group (0%) were found to have intrathoracic lymph node enlargement. With pooled OR of 31.90 (95%CI: 3.65 to 278.98, P=0.002) it was demonstrated that patients with intrathoracic lymph node enlargement were more likely to progress into severe Covid-19.
In 2 trials reporting data on pleural effusions [15, 21], 12 of 39 patients in Severe group (30.8%) and 9 of 145 in Non-severe group (6.2%) were found to have pleural effusions. With pooled OR of 10.84 (95%CI: 1.07 to 109.80, P=0.04) it was demonstrated that patients with pleural effusions were more likely to progress into severe Covid-19. The outcome was explicitly expressed in Table 2.