Clinical Characteristics and Immune Injury Mechanisms in 71 Patients with COVID-19.

The outbreak of coronavirus disease 2019 (COVID-19), caused by the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a threat to global health. The mortality rate of severely ill patients in the early stage is 32.5%. The exacerbation of the condition and death of patients are closely associated with inflammatory cytokine storms, which are caused by excessive activation of the immune and complement systems as well as the coinfection of other pathogens. However, the immunological characteristics and the mechanisms underlying inflammatory storms have not been well elucidated. Here, we analyzed the clinical and immunological characteristics of 71 confirmed COVID-19 patients. Based on the National Health Commission of China (NHCC) guidelines, patients were stratified into mild and severe types. We compared the clinical and laboratory data obtained from electronic medical records between the two types. In regard to the hematological parameters, COVID-19 patients showed decreased erythrocyte count, hemoglobin, hematocrit, lymphocyte count, eosinophil count, and complement C1q, whereas neutrophils, C-reactive protein, and procalcitonin were significantly increased, especially in severe cases. We also found that CD3+ CD4+ T lymphocytes, CD3+ CD8+ T lymphocytes, CD19+ B lymphocytes, and CD16+ CD56+ NK cells in the peripheral blood of all patients were decreased. In addition, CD3+ CD8+ T lymphocytes, CD16+ CD56+ NK cells, and complement C1q in severely ill patients decreased more significantly. Additionally, interleukin 6 (IL-6) elevation was particularly prominent in all patients, especially in severe cases. These results suggest that CD3+ CD8+ T lymphocytes, CD16+ CD56+ NK cells, C1q as well as IL-6 may play critical roles in the inflammatory cytokine storm. The dysregulation of these aforementioned immune parameters, along with bacterial coinfection, were the important causes of exacerbation of the patients' condition and death. This study improves our understanding of the immune dysregulation of COVID-19 and provides potential immunotherapeutic strategies.IMPORTANCE The dysregulation of CD3+ CD8+ T lymphocytes, CD16+ CD56+ NK cells, C1q as well as IL-6, along with bacterial coinfection, were important causes of exacerbation of the patients' condition and death.

Clinical outcomes of 402 patients with COVID-2019 from a single center in Wuhan, China.

The outbreak of SARS-CoV-2 has become a pandemic with significant mortality. Published studies described clinical characteristics of the disease contain small cohorts from individual centers or larger series consisting of mixed series from multiple different hospitals. We report here analyses of mortality and disease severity among 402 patients from a single hospital. The cohort includes 297 patients with confirmed and 105 with clinical diagnosis. The latter group consists of cases with inconclusive nucleic acid test but meeting the criteria for clinical diagnosis. Data are compared between sexes and among different age groups. The overall case fatality is 5.2%. However, age at 70 years or older is associated with a significantly higher mortality (17.8%) and higher rate of severe and critical illness (57.5%). Case fatality is 8% in patients 50 years of age or older, and 1.2% in those younger than 50 years. In addition, case fatality is 7.6% in male patients, as opposed to 2.9% in females, demonstrating a clear sex difference.

Analysis of Mortality in Patients With COVID-19: Clinical and Laboratory Parameters.

BACKGROUND: Several reports on epidemiological and clinical features of the 2019 coronavirus disease (COVID-19) have been published. However, mortality and morbidity analyses, important for better understanding the pathogenesis of this disease, are scarce. We examine the clinical and laboratory features of 14 patients who died of COVID-19. METHODS: The cohort consisted of 11 male and 3 female patients, with 9 patients aged 70 years or above, and nearly all had underlying diseases. RESULTS: Fever with bilateral pneumonia was the main manifestation. Most patients had consolidations combined with ground glass opacity (GGO) on chest computed tomography scan. Laboratory tests showed lymphocytopenia in 10 patients, high blood glucose in 11, GGT in 5 of the 14 patients, and high LDH in 5 of 6 patients tested. In addition, this cohort had high level of cytokines such as interleukin-6 in all 8 patients tested. CONCLUSIONS: The clinical and laboratory parameters in the cohort of fatal cases may be incorporated into future clinical prognosis models and will be of help in understanding the pathogenesis of this disease.