Clinical characteristics of COVID-19 patients
We collected clinical information of 91 patients diagnosed with COVID-19 in Jingzhou Central Hospital. Of these patients, 30 (33.0%) were assessed as severely ill (Table 1). The median age was 46.0 years old in total, and severe patients were generally older with a median age of 50.5 compared with 42.0 for the mild cases (P=0.049). Slightly more than half (53.8%) of the patients were men, and there were no significant differences in the sex ratio between severe and mild cases (P=0.230). Twenty one (23.1%) patients had one or more coexisting medical conditions, including hypertension, diabetes, chronic obstructive pulmonary disease (COPD), kidney disease, and malignancies. Coexisting medical conditions were more prominent in the severe group (40% of them had chronic disease, compared to 14.8% in mild group (P=0.009)). The median duration from first symptoms to hospital admission was four days. All the patients were confirmed with qPCR positive eventually, while only 73.6% of the patients were qPCR positive when they first received the test. And qPCR positive rate at different time was not different in severe and mild groups (P=0.884). In addition, the vital signs (pulse rate, temperature, and mean arterial pressure) between two groups showed no significant differences. Compared to the severe group (6.7%), the mild group (19.7%) had higher proportion of discharged cases. Of the two dead patients who were critically ill, one had lung cancer and the other hypertension. Both of them had suffered respiratory and acute renal failure on the day of admission. As for follow up, 14 patients were discharged with an average hospital stay of 13.67 days. The mortality at the Jingzhou Central Hospital was 2.2%. Taken together, our results indicated that older patients with chronic disease were more likely to become critically ill, and negative qPCR for once or twice could not exclude the virus infection at onset of symptoms.
At data cut off, considering 91 evaluable patients, the most common symptoms were fever (75, 82.4%) and cough (59, 64.8%), followed by fatigue (35, 38.5%), chest distress (21, 23.1%), chill (21, 23.1%), pharyngalgia (19, 20.9%), and myalgia (15, 16.5%) (Fig. 1). Additionally, some patients reported about gastrointestinal problems, including diarrhea (14, 15.4%) and nausea (19, 12.1%). The symptoms of polypnea and disturbance of consciousness, signs of severe conditions, were reported by 12.1% (19) and 3.3% (3) of patients, respectively. Anorexia, arthrodynia, dizziness and abdominal pain were also found (Fig. 1).
Baseline characteristics of laboratory tests in COVID-19 patients.
To explore the characteristics of lab tests in patients with COVID-19, the baseline hematological and biochemical indices of 91 patients with COVID-19 were analyzed (Table 2). On admission, 51.6% of patients had lymphopenia, which was more prominent in mild cases (Table 2). Elevated CK was seen in 15.4% of patients. Elevated ALT and AST was seen in 11.0% and 19.8% of patients. Severe cases had more prominently elevated Cr (16.7% vs 0%, P<0.001) and CK (26.7% vs 9.8%, P=0.018), compared with mild cases. Prothrombin time (PT) was prolonged in 20.9% of patients. Levels of interleukin 6 (IL-6) and c-reactive protein (CRP), two biomarkers inflammation, increased in 19.8% and 40.7% of patients (Table 2). The lab findings indicated that COVID-19 might result in liver, kidney and cardiovascular injury.
Non-respiratory system injury with COVID-19
Interestingly, besides the respiratory system, COVID-19 patients showed signs of multiple
organ injury on admission, including 18 cases (19.8%) of liver injury, 14 cases (15.4%) of cardiovascular damage with abnormal increase of troponin, CK or CK-MB, five cases (5.5%) of acute renal injury, and 19 (20.9%) cases of poor coagulation function (Table 3). Together, 28 patients (30.8%) suffered non-respiratory system injury, with an especially higher rate (50%, P=0.003) in severe group (Table 3). Further analysis showed that severe patients tended to suffer damage of the cardiovascular system (50.0% vs 21.3%, P=0.04) and renal function (16.7% vs 0%, P=0.003) (Table 3). Angiotensin converting enzyme II (ACE2) was proved to be the cell receptor of COVID-19 [7], the same as SARS infection [8]. We performed bioinformatics analysis on the expression of ACE2 receptors in different normal tissues from Oncomine, as shown in additional file 1. The data indicated that the highest level of ACE2 were in the ileum, followed by testis, diaphragm, heart, kidney, seminal vesicle, colon, and respiratory tract. Hence, we speculated that the high ACE2 expression in the ileum, heart, kidney and colon caused the virus direct infection in specific organs, which might explain the high rate of multiple organ damage caused by COVID-19.
Typical CT images
All of the patients in our study presented the exudative change, with different degrees of patchy consolidation or ground-glass opacities (Fig. 2a–c). The processing of CT images (Fig. 2a) revealed that the chest displayed only scattered dotted shadows on the first day of admission, focal exudation on the fourth day, and diffuse ground-glass shadows on the 13th day. A good example of gradually improved condition with effective therapy is presented in Fig. 2b. In addition, there were patients whose condition progressed rapidly within a week (Fig. 2c). On the first day of admission, the chest CT examination was basically normal. However, on the seventh day, chest CT showed a patchy high-density shadow and a diffused ground glass density shadow in both lungs. Soon after, this patient died of multiple organ failure. These results suggest that CT scanning is an important method of differential diagnosis and evaluating the severity of COVID-19.
Main treatment measures of COVID-19 patients during hospitalization.
Most patients received antiviral therapy (81, 89.0%), glucocorticoid therapy (79, 86.8%), and antibacterial therapy (90, 98.9%), which was given to all severe patients (30, 10.0%) (Table 4). Oseltamivir, lopinavir/ritonavir, and Abidol were common antiviral drugs used in our study. In our study, 26.4% of patients were treated with oseltamivir antiviral therapy (Table 4). Lopinavir/ritonavir was more likely to be used in the mild group (53.3% vs. 78.7%, P=0.013). Arbidol was more likely to be used in the severe group (73.3% vs. 50.8%, P=0.033). Supportive treatment measures, including oxygen therapy (29, 31.9%), mechanical ventilation (5, 5.5%), infusion of immunoglobulin (35, 38.5%), and continuous renal replacement therapy (CRRT) (3, 3.3%), were more likely to be applied to severe group (P<0.05) (Table 4).