Demographic characteristics.
As of March 11, 2020, a total of 146 patients were confirmed in the four hospitals and transferred to the isolation hospital for treatment. We obtained basic information, clinical data and CT images of 143 patients (96.6%), among whom 66 were females (46.2%) and 77 males (53.8%). Demographic and clinical characteristics of the patients are shown in Table 1. On admission, the degree of severity of COVID-19 was categorized as non-severe in 110 patients and severe in 33 patients. Of all patients, 60 patients (42.0%) had contact with a confirmed patient, 70 patients (49.0%) had contact with a person in the Wuhan area, 4 patients (2.8%) had contact with both, and 9 patients (6.3%) had an unclear contact history. The median age of patients was 47 years old (range 4-86), with a high concentration of 38-60 years old (56.8%).
The median age of the non-severe patients was 44.5 years old (range 4-80), while the median age of the severe patients was 55.0 years old (range 27-86), and the difference was statistically significant (P<0.05).The number of young patients (<38 years old) in the non-severe group (32.7%) was higher than that in the severe group (0.9%), and the difference was statistically significant (P<0.05).The proportion of old patients(>60 years old) in the severe group (45.5%) was greater than that in the non-severe group (15.5%), and the difference was statistically significant (P<0.05). 129 patients (90.2%) had a history of smoking, including 100 patients (90.9%) in the non-severe group and 29 patients (87.9%) in the severe group, with no statistically significant difference.
The mean incubation period was 6.9 days (SD3.472) and the mean treatment delay period was 3.0 days (SD2.631). Fever (73.4%) was the most common symptom. And a total of 91patients (63.6%) developed cough, with sputum (28.7%), yellow sputum (5.6%) and dry cough (29.4%). Sore throat (10.5%), Nasal congestion (5.6%), muscle soreness (9.8%), and chest tightness (17.5%) were relatively rare. Among the overall population, 24.5% had at least one coexisting illness (e.g., hypertension and chronic obstructive pulmonary disease). The average body temperature of patients with fever was 38.0℃ (SD3.741), mainly in 37℃-39℃, and only 1 case (0.7%) had high fever (>40℃).
Differences in laboratory results between the two groups of patients
Some of the patients were first admitted to the county hospital, and some laboratory tests were not carried out due to conditions. A total of 123 cases were included for laboratory examination results analysis, and those without such examination were recorded as UNKOWN. There were 28 cases in the severe group and 95 cases in the non-severe group. Table 2 shows the details of laboratory results of all cases. In the non-severe group, except for the increase of blood glucose (14 (± 60) mmol/L), the decrease of serum albumin (39 (± 5.2) g/L), the decrease of erythrocyte sedimentation rate (35 (± 24) umol/L), the decrease of serum sodium (130 (± 25) mmol/L), the increase of CRP (15 (± 19) mg/L), and the increase of amyloid A (190 (± 330)). All other test results were within the normal range.
In the severe group, the lymphocyte count decreased (0.91 (± 0.43)*10^9), the erythrocyte sedimentation rate (38 (± 24) umol/L) decreased, the blood glucose (13 (± 53) mmol/L) increased, the lactate dehydrogenase (350 (± 180) U/L) increased, the serum albumin (130 (± 25) g/L) decreased, the CPR (35 (± 31) mg/L) increased, and the glomerular filtration rate (82 (± 26)ml/min) decreased. Amyloid protein A (430 (+ 420)) increased, the fibrinogen detection value (4.5(± 1.3) s) increased, the D dimer (0.54 g/L (± 0.63)) increased, the PH (7.8(± 2.0)) increased, the arterial blood oxygen partial pressure (83 (± 24) mm/Hg) decreased. And the calcitonin original (0.086 (±0.090 mm) ug/L) level is reduced, the myoglobin (84 (± 80)ng/ml), IL - 10 (9.4(± 9.2) pg/ml),C1q (240 (± 38) mg/L) increased, the PT (16 (± 19)s) increased, the absolute value of CD3 (490 (± 330) /uL) increased, the absolute value of TCD3 (56 (± 13) %) decreased, the absolute value of CD4 (290 (± 200) /uL) decreased, and the absolute value of CD8 (190 (± 130) /uL) decreased. Other test results were within the normal range.
In addition, the result of following laboratory test items were different, such as aspartate transaminase, creatine kinase and lactate dehydrogenase, serum albumin, CPR, glomerular filtration rate, amyloid protein A, fibrinogen, calcitonin level, oxygen partial pressure, red protein, IL - 10, the absolute value of CD3, and the absolute value of CD4, the absolute value of CD8.The difference between the two groups was statistically significant (P<0.05) (table2).
CT manifestations of the two groups
Five (3%) CT images were unable to be evaluated due to poor respiratory artifact quality. Images of 138 (97%) patients at admission were obtained. Among them, 34 patients were severe (31%) and 104 patients were non-severe (75%). The lesions of 135 patients (98 %) mainly distributed in the external or subpleural of lung, 37 patients (27 %) in the middle or inner band, and 34 patients (25%) in both. Among them, the lesions in the middle or inner band were more common seen in non-severe patients (47% vs 20%), and the difference was statistically significant (P=0.004). Mass (81%) is the most common lesion shape, followed by patchy (68%). The shapes of lung segments and irregular were seen only in the severe patients, while the nodular shape was seen only in the non-severe patients. Most of the lesions presented with mixed density (63 %) and uneven density (73 %).
In 60% of the CT images, the lesion was distributed along the pulmonary texture tract, and in 62% of the CT images, the lesion was adjacent to vasodilation. There were 52% CT images showing interlobular septal thickening, and fibrous foci were present in 30% of the CT images. Other concomitant signs such as cavitation or calcification (1%), enlarged lymph nodes (3%), pleural effusion (2%), chronic bronchitis (4%), emphysema or pulmonary bullous (4%) are rare. Consolidation (68% vs 41%), bronchial inflation signs (59% vs 41%), and bronchiectasis (71% vs 39%) were more common in the severe group, and the difference was statistically significant(P<0.05).
All the discharged patients (61/143) showed obvious absorption of lesions on CT. Figure1 shows the CT transformation of a discharged patient from admission to discharge.
Treatment and clinical outcomes.
81patients (56%) received oxygen therapy and 95 (65%) received antiviral therapy. 16 patients (11%) were treated with intravenous glucocorticoids, 11 of whom were in the severe group. 9 patients (6%) were treated with gamma globulin and 21 (15%) with antibiotics. Noninvasive respiratory support was used in 29 patients (20%) and invasive respiratory support was used in 1 severe patient. As of March 11, 2020, the final date of follow-up, all patients were discharged from the hospital, with no deaths.