Key words:
coronavirus disease 2019; severity; clinical characteristics; risk
factors; mortality
Introduction
The emerging pandemic of coronavirus disease 2019 (COVID-19), an
infectious disease caused by a novel strain of human coronaviruses, the
severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2),1 has become worldwide the focus of
attention. Since its first report in late December 2019 in Wuhan,
China,2 COVID-19 has aggressively spread across the
world and dramatically impacted people’s health and daily life. As of
June 7, 2020, according to the Situation Report issued by the World
Health Organization (WHO), the number of confirmed COVID-19 cases were
reported in over two hundred countries/areas and exceeded 6.9 million,
with about 397,000 reported deaths.3 The clinical
patterns of COVID-19 ranged from asymptomatic cases to critically ill
patients.4 Fever, dry cough, and radiological changes
in lungs tend to be the common clinical manifestations in COVID-19
patients. Severe viral pneumonia with respiratory failure and the
deterioration of underlying diseases are the main cause of death of
severe patients. According to the data provided by the China National
Health Commission, the mortality rate of COVID-19 patients was 7.7% in
Wuhan,5 which was higher to that in the world at
present (5.8%).3
As the number of infected and fatal cases are dramatically increasing
throughout the world, it is vital to reveal the clinical, radiological
and laboratory characteristics, and more importantly, the risk factors
of mortality in severe COVID-19 patients. Our previous study found that
higher levels of C-reactive proteins (CRP), D-dimer and procalcitonin
(PCT) were associated with severe patients when compared to non-severe
patients.6 However, the risk factors for mortality of
the COVID-19 patients have not yet been well described. Elder age, the
presence of comorbidities , leukocytosis, high level of D-dimer, lactate
dehydratase (LDH) and low platelet counts were reported to be the risk
factors associated with in-hospital death of severe
patients.7-11 Due to the distinct criteria used for
severe and/or critically ill patients, the prediction value of these
risk factors for death in severe patients may be diverse.
The purpose of this study is to compare the clinical, radiological and
laboratory characteristics and longitudinal variations in laboratory
parameters of the 289 hospitalized patients with COVID-19 with different
severity and clinical outcomes. Potential risk factors and clinical
findings associated with death in severe COVID-19 patients were
analyzed.
Methods2.1 Study design and patients’ enrollment
Hospitalized patients admitted to Zhongnan hospital of Wuhan University
(n=178) and No.7 hospital of Wuhan (n=241) (admission date between Dec
29th, 2019 and Feb 16th, 2020), who
were diagnosed as ‘viral pneumonia’ according to the clinical symptoms
and chest CT images were primarily enrolled in this study. 289 patients
with positive real-time reverse transcription–polymerase chain reaction
(rRT-PCR) results of SARS-CoV-2 nucleic acid test were diagnosed as
COVID-19 and included in the analysis set. According to the disease
severity and clinical outcome, these patients were divided into three
groups: 1) non-survived cases; 2) survived severe cases; 3) non-severe
cases. All the patients were treated following the guidance issued by
China National Health Commission (trial version
3-5).12 In accordance with the criteria stated in the
guidance13 for hospital discharge of a COVID-19
patient, all the following four conditions should be met: 1) normal
temperature lasting longer than 3 days; 2) significantly improved
respiratory symptoms; 3) substantially improved acute exudative lesions
on chest CT images; 4) two consecutive negative nucleic acid test
results of respiratory tract samples (at least 24 hours apart). To be
noticed, part of the result of these patients had been reported as
letter to editor in Allergy which only demonstrated the
difference of clinical characteristics between patients with initial
negative and positive nucleic acid results of
SARS-CoV-2.6 This study was approved by the Zhongnan
Hospital of Wuhan University institutional ethics board (No.2020015 and
No. 2020028).