Clinical Characteristics of SARS-CoV-2 Pneumonia Compared to Controls in Chinese Han Population

Background In December 2019, novel coronavirus (SARS-CoV-2) infected pneumonia occurred in Wuhan, China. The number of cases has increased rapidly but information on the clinical characteristics of SARS-CoV-2 pneumonia without comorbidities compared to normal controls in Chinese Han population is limited. Our objective is to describe the epidemiological and clinical characteristics of SARS-CoV-2 pneumonia without comorbidities compared to normal controls in the Chinese Han population. Methods Retrospective, multi-center case series of the 69 consecutive hospitalized patients with confirmed SARS-CoV-2 pneumonia, from February 7 to February 28, 2020; final date of follow-up was February 29, 2020. Results The study population included 69 hospitalized patients with confirmed SARS-CoV-2 pneumonia without comorbidities and 14,117 normal controls. 50.7% patients were male and 49.3% were female; 1.5% patients were asymptomatic cases, 63.8% patients were mild cases, and 36.2% patients were severe or critical cases. Compared with mild patients (n=44), severe or critical patients (n=25) were significantly older (median age, 67 years [IQR, 58-79] vs. 49 years [IQR, 36-60]; p<0.01). Fever was present in 98.6% of the patients. The second most common symptom was cough (62.3%), fatigue (58.0%), sputum (39.1%), and headache (33.3%). The median incubation period was 4 days (IQR, 2 to 7). Leukocyte count was 74.1% of normal controls and lymphocyte count was 45.9% of normal controls. The phenomenon of lymphocyte depletion (PLD) observed in severe or critical cases in 100%. Levels of lactate dehydrogenase, D-dimer, procalcitonin, and interleukin-6 were showed significant differences between mild and severe or critical cases. Chest computed tomographic scans showed bilateral patchy patterns (49.3%), local patchy shadowing (29.0%), and ground glass opacity (21.7%). 7.3% patients were diagnosed ARDS, 7.3% patients were diagnosed acute cardiac injury (troponin I >28 pg/mL) and 4.4% patients were diagnosed fungal infections or shock. 4.3% patients have been discharged; 1.5% patient had died; 1.5% patient had recovery. Conclusions In this multicenter case series of 69 patients without comorbidities, the full spectrum of asymptomatic, mild, severe, and critical cases is described. 50.7% patients were male and 49.3% were female; 1.5% patients were asymptomatic cases, 63.8% patients were mild cases, and 36.2% patients were severe or critical cases. 4.3% patients have been discharged; 1.5% patient had died; 1.5% patient had recovery. Among the 25 patients with severe or critical disease, 12.0% patients were underwent non-invasive mechanical ventilation, 8.0% patients underwent invasive mechanical ventilation, and 4.0% patients died.