Demographic and Clinical Findings
Table 2 shows the demographic and clinical data of patients at baseline. The mean age ± SD of patients was 55.37 ± 13.93 years (range: 31-86) among males and 50.29 ± 15.92 years (range: 26-84) among females; 72.1% were males. The most common clinical manifestations in our patients were dry cough (79.1%), fever (73.3%), and dyspnea (62.8%). Approximately a quarter of the patients suffered from cardiovascular diseases, but 65.1% reported no comorbidity. Of the total 86 patients, 69 (80.2%) and 13 (15.1%) patients were classified as cases with favorable and severe outcomes (respectively), and four (4.7%) were lost to follow-up. Among patients in the severe group, seven (8.1%) were intubated, four (4.7%) were admitted to the ICU, and two (2.3%) died on follow-up. Patients with severe outcomes were significantly older than patients in the favorable group (p< 0.001). Although the respiratory rate was markedly different across the two groups (p =0.041), SpO2 and pulse rate were not statistically different between patients with favorable and severe outcomes. The mean ± SD clinical score of all patients was 8.16 ± 2.69; patients in the severe group scored significantly higher in terms of clinical severity (p <0.001) (Table 2).
Table 2- Patients’ Baseline Demographic and Clinical Data.
|
Total patients
(n=86)
|
Favorable group
(n=69)
|
Severe group
(n=13)
|
p-value
|
Age, years
Mean ± SD
Range
|
53.95 ± 14.60
26 - 86
|
51.10 ± 13.19
26 - 84
|
71.30 ± 9.55
53 -86
|
<0.001
|
Sex, n (%)
Female
Male
|
24 (27.9)
62 (72.1)
|
19 (27.5)
50 (72.5)
|
3 (23.1)
10 (76.9)
|
> 0.999
|
Smoking history‡, n (%)
Positive
Negative
|
6 (7.0)
80 (93)
|
5 (7.2)
64 (92.8)
|
1 (7.7)
12 (92.3)
|
> 0.999
|
Clinical Symptoms, n (%)
Dyspnea
Fever
Dry cough
Coryzal symptoms
Hemoptysis
Chest pain
Headache
Myalgia
Productive cough
|
54 (62.8)
63 (73.3)
68 (79.1)
2 (2.3)
4 (4.7)
16 (18.6)
42 (48.8)
49 (57)
22 (25.6)
|
45 (65.2)
50 (72.5)
56 (81.2)
2 (2.9)
3 (4.3)
14 (20.3)
34 (49.3)
36 (52.2)
18 (26.1)
|
8 (61.5)
11 (84.6)
8 (61.5)
0 (0)
1 (7.7)
1 (7.7)
6 (46.2)
10 (76.9)
3 (23.1)
|
> 0.999
0.498
0.146
> 0.999
0.506
0.445
> 0.999
0.132
> 0.999
|
Comorbidities, n (%)
Cardiovascular
DM, COPD, immunocompromised
Other†
None
|
20 (23.3)
12 (14)
9 (10.5)
56 (65.1)
|
15 (21.7)
5 (7.2)
6 (8.7)
48 (69.6)
|
5 (38.5)
7 (53.8)
3 (23.1)
4 (30.8)
|
0.288
<0.001
0.149
0.012
|
SpO2 (%)
Mean (SD)
Range
|
91.14 ± 5.97
66 -99
|
91.33 ± 5.91
66 - 99
|
88.54 ± 6.08
76 - 97
|
0.073
|
Respiratory rate (/min)
Mean (SD)
Range
|
21.16 ± 4.77
14-40
|
20.72 ± 4.27
14- 32
|
24.23 ± 6.29
17 - 40
|
0.041
|
Pulse rate (/min)
Mean (SD)
Range
|
94.73 ± 16.74
55 -131
|
93.79 ± 16.56
55 - 127
|
97.46 ± 18.30
69 -131
|
0.675
|
DM = Diabetes Mellitus, COPD = Chronic Obstructive Pulmonary Disease
‡ Positive smoking history was defined as ex/current smoker with ≥ 10 pack/year smoking history.
† Other includes any disease except cardiovascular, DM, COPD, or immunocompromising conditions.
Imaging Findings
Table 3 summarizes the chest CT findings of enrolled patients. The mean ± SD interval from symptom onset to initial CT scan was 6.84 ± 4.41 days (range: 1 – 21). The patients' mean ± SD effective radiation dose was 1.2 ± 0.7 mSv, with a mean tube current of 33.52 ± 19.82 mAs. The inter-reader ICC for the CT scoring system was excellent (n=86, ICC= 0.95). As shown in Table 3, the mean CT score was significantly higher in patients who had developed severe events (p=0.012). Nonetheless, the highest CT score (20) was seen in a 65-year-old male patient who had also developed pleural effusion. On follow-up, this patient recovered entirely after receiving outpatient treatment.
Considering lobar involvement, the RLL (96.5%) and LLL (93%) were the most frequently involved. Furthermore, the number of involved lobes was significantly higher in patients experiencing severe outcomes (p=0.046). GGO (59.3%) and consolidation (24.4%) were the predominant findings in the chest CT of our patients (Figure 1, 2 & 3); however, rounded morphology was also a frequent finding, reported in 23.3% of our patients (Figure 4). Of note, bronchiectasis was not seen in our patients, and pericardial effusion was seen in only one case with severe outcomes (Table 3).
Table 3- Patients’ Chest CT scan Findings.
|
Total patients (n=86) |
Favorable group (n=69) |
Severe group (n=13) |
p-value |
The interval between symptom onset and the first CT‡ scan (day)
Mean ± SD
Range
|
6.84 ± 4.41
1-21
|
6.80 ± 4.40
1-21
|
6.82 ± 5.27
3-20
|
0.736
|
Dose-Length Product (mGy*cm)
Mean ± SD
Range
|
85.02 ± 55.27
34.8 -399.9
|
85.93 ± 59.40
34.8 - 399.9
|
81.57 ± 38.31
43.4 – 189.2
|
0.914
|
Tube current (mAs)
Mean ± SD
Range
|
33.52 ±19.82
15 -150
|
34.36 ± 21.65
15 -150
|
29.17 ± 6.95
17-37
|
0.661
|
Lobar Involvement, n (%)
Right upper lobe
Right middle lobe
Right lower lobe
Left upper lobe
Lingula
Left lower lobe
|
72 (83.7)
67 (77.9)
83 (96.5)
71 (82.6)
66 (76.7)
80 (93)
|
57 (82.6)
54 (78.3)
68 (98.6)
55 (79.7)
52 (75.4)
64 (92.8)
|
13 (100)
12 (92.3)
13 (100)
13 (100)
13 (100)
12 (92.3)
|
0.198
0.446
> 0.999
0.111
0.060
> 0.999
|
Number of involved lobes, n (%)
1
2
3
4
5
6
|
3(3.5)
5 (5.8)
6 (7)
7 (8.1)
8 (9)
57 (66.3)
|
1 (1.4)
4 (5.8)
6 (8.7)
6 (8.7)
8 (11.6)
44 (63.8)
|
0 (0)
0 (0)
0 (0)
1 (7.7)
0 (0)
12 (92.3)
|
0.046
|
Lesion Distribution, n (%)
Axial
Central
Peripheral
Diffuse
Craniocaudal
Lower
Middle
Upper
Diffuse
Anteroposterior
Anterior
Posterior
Diffuse
|
3 (3.5)
51 (59.3)
32 (37.2)
35 (40.7)
9 (11.6)
3 (3.5)
40 (46.5)
2 (2.3)
49 (57)
35 (40.7)
|
2 (2.9)
40 (58)
27 (39.1)
28 (40.6)
8 (9.3)
1 (1.4)
32 (46.4)
1 (1.4)
40 (58)
28 (40.6)
|
1 (7.7)
8 (61.5)
4 (30.8)
6 (46.2)
0 (0)
2 (15.4)
5 (38.5)
1 (7.7)
7 (53.8)
5 (38.5)
|
0.633
0.104
0.480
|
Predominant Pattern, n (%)
Ground-glass opacification
Consolidation
Mixed
Reticular
|
51 (59.3)
21 (24.4)
13 (15.1)
1 (1.2)
|
42 (60.9)
16 (23.2)
11 (15.9)
1 (1.4)
|
6 (46.2)
5 (38.5)
1 (7.7)
0 (0)
|
0.323
0.302
> 0.999
> 0.999
|
Other Abnormal Findings, n (%)
Pleural effusion
Pericardial effusion
Emphysema
Fibrosis
Bronchiectasis
Bronchial wall thickening
Crazy-paving pattern
Halo sign
Reversed-halo sign
Rounded morphology
Band-like opacities
Lymphadenopathy (SAD†>10mm)
|
8 (9.3)
1 (1.2)
2 (2.3)
2 (2.3)
0 (0)
3 (3.5)
6 (7)
8 (9.3)
7 (8.1)
20 (23.3)
15 (17.4)
9 (10.5)
|
6 (8.7)
0 (0)
2 (2.9)
2 (2.9)
0 (0)
3 (4.3)
5 (7.2)
8 (11.6)
6 (8.7)
16 (23.2)
11 (15.9)
6 (8.7)
|
2 (15.4)
1 (7.7)
0 (0)
0 (0)
0 (0)
0 (0)
1 (7.7)
0 (0)
0 (0)
3 (23.1)
4 (30.8)
3 (23.1)
|
0.606
0.159
> 0.999
> 0.999
> 0.999
> 0.999
0.917
0.344
0.583
> 0.999
0.243
0.149
|
CT score
Mean ± SD
Range
|
7.60 ± 6.5
1 - 20
|
7.47 ± 3.91
1 - 20
|
9.54 ± 3.25
5 - 17
|
0.012
|
‡ CT: computed tomography
†SAD: short-axis-diameter
ROC Curve for CT scoring
The ROC curve analysis for the CT score is shown in Figure 5. The area under the ROC curve for discriminating patients with the severe outcome from those with favorable outcomes was 0.721 (standard error, 0.063; 95% CI, 0.595-0.841), and the optimal CT score threshold for identifying severe patients was 7.5, with 77% sensitivity and 65% specificity. Furthermore, logistic regression analysis showed that one point increase in CT score increases the odds of having a severe outcome by 19% (p = 0.032).
ROC Curve for Clinical Scoring
The ROC curve analysis for clinical score is shown in Figure 6. The area under the ROC curve for discriminating patients with favorable and severe outcomes was 0.832 (standard error, 0.052; 95% CI, 0.731-0.933). The optimal cut-off for identifying severe patients was 9.25, with 92.3% sensitivity and 72.1% specificity. Logistic regression analysis showed that one point increase in the clinical score increases the odds of having a severe outcome by 51% (p < 0.001).