ObjectiveTo investigate the clinical characteristics and contribution factors in severe coronavirus disease 2019 (COVID-19).MethodsThe clinical symptoms, laboratory findings, radiologic data, treatment strategies, and outcomes of 110 COVID-19 patients were retrospectively analyzed in these hospitals from Jan 20, 2020 to Feb 28, 2020. All patients were confirmed by fluorescence reverse transcription polymerase chain reaction. They were classified into a non-severe group and a severe group based on their symptoms, laboratory and radiologic findings. All patients were given antivirus, oxygen therapy, and support treatments. The severe patients received high-flow oxygen therapy, non-invasive mechanical ventilation, invasive mechanical ventilation or extracorporeal membrane oxygenation. The outcomes of patients were followed up until March 15, 2020. Contribution factors of severe patients were summarized from these clinical data.ResultsThe median age was 50 years old, including 66 males (60.0%) and 44 females (40.0%). Among them, 45 cases (40.9%) had underlying diseases, and 108 cases (98.2%) had different degrees of fever. The common clinical manifestations were cough (80.0%, 88/110), expectoration (33.6%, 37/110), fatigue (50.0%, 55/110), and chest tightness (41.8%, 46/110). Based on classification criteria, 78 (70.9%) non-severe patients and 32 (29.1%) severe patients were identified. Significant difference of the following parameters was found between two groups (P<0.05): age was 47 (45, 50) years vs. 55 (50, 59) years (Z=–2.493); proportion of patients with underlying diseases was 27 (34.6%) vs. 18 (56.3%) (χ2=4.393); lymphocyte count was 1.2 (0.9, 1.5)×109/L vs. 0.6 (0.4, 0.7)×109/L (Z=–7.26); C reactive protein (CRP) was 16.2 (6.5, 24.0) mg/L vs. 45.3 (21.8, 69.4) mg/L (Z=–4.894); prothrombin time (PT) was 15 (12, 19) seconds vs. 18 (17, 19) seconds (Z=–2.532); D-dimer was 0.67 (0.51, 0.82) mg/L vs. 0.98 (0.80, 1.57) mg/L (Z=–5.06); erythrocyte sedimentation rate (ESR) was 38.0 (20.8, 59.3) mm/1 h vs. 75.5 (39.8, 96.8) mm/1 h (Z=–3.851); lactate dehydrogenase (LDH) was 218.0 (175.0, 252.3) U/L vs. 325.0 (276.5, 413.5) U/L (Z=–5.539); neutrophil count was 3.1 (2.1, 4.5)×109/L vs. 5.5 (3.7, 9.1)×109/L (Z=–4.077). Multivariable logistic analysis showed that there was positive correlation in elevated LDH, CRP, PT, and neutrophil count with the severity of the disease. Currently, 107 patients were discharged and 3 patients died. Total mortality was 2.7%.ConclusionsOld age, underlying diseases, low lymphocyte count, elevated CPR, high D-dimer and ESR are relevant to the severity of COVID-19. LDH, CPR, PT and neutrophil count are independent risk factors for the prognosis of COVID-19.