key: cord-327138-l2m2g0v8 authors: Ren, Chao; Yao, Ren-Qi; Ren, Di; Li, Ying; Feng, Yong-Wen; Yao, Yong-Ming title: Comparison of clinical laboratory tests between bacterial sepsis and SARS-CoV-2-associated viral sepsis date: 2020-08-04 journal: Mil Med Res DOI: 10.1186/s40779-020-00267-3 sha: doc_id: 327138 cord_uid: l2m2g0v8 Sepsis is a life-threatening condition that is characterized by multiple organ dysfunction due to abnormal host response to various pathogens, like bacteria, fungi and virus. The differences between viral and bacterial sepsis are indeed of great significance to deepen the understanding of the pathogenesis of sepsis, especially under pandemics of SARS-CoV-2 infection. ICU of the Second People's Hospital of Shenzhen, China. Demographic characteristics, comorbidities, and laboratory findings on ICU admission and clinical outcomes were collected. Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were calculated within the first 24 h since ICU admission. The bacterial and viral sepsis were identified by blood culture and metagenomic next-generation sequencing. Twenty-one patients with SARS-CoV-2-induced sepsis and 46 patients with bacterial sepsis were finally recruited (Additional file 2). The median age was 64.0 years (IQR, 60.5-68.0) and 65.5 years (IQR, 49.3-77.3) for patients of SARS-CoV-2-induced sepsis and bacterial sepsis, respectively (Additional file 1). The prognostic scoring system, including SOFA [6.0 (IQR, 4.0-9.0) vs. 4.0 (IQR, 3.5-5.0), P = 0.01] and APACHE II [17.0 (IQR, 13.0-20.3) vs. 8.0 (IQR, 6.5-9.5), P < 0.001] were consistently higher among patients with bacterial sepsis than those with SARS-CoV-2-induced sepsis. Meanwhile, ICU mortality rates were significantly higher in patients with bacterial sepsis than those with viral sepsis [34.8% (16/46) vs. 4.8% (1/21), P = 0.013]. As presented in Table 1 , absolute counts of T lymphocytes, cytotoxic T lymphocytes (Tc), and helper T lymphocytes (Th) were significantly lower among patients White blood cell counts (× 10 9 /L) 3.5-9.5 9.6 (6.1-15.9) 7.0 (4.7-10.9) 11.7 (6.6-17.3) 0.007 Neutrophil counts (× 10 9 /L) 1.8-6.3 9.0 (4.3-13.9) 5.8 (3.6-8.9) 11.1 (5.5-15.3) 0.003 Lymphocyte counts (× 10 9 /L) 1.1-3. Data were median (IQR) if not otherwise specified. n (%) referred to the total number of patients with available data. P values indicated differences between SARS-CoV-2-induced sepsis and bacteria-induced sepsis, in which P < 0.05 was deemed as statistical significance SD Standard deviation, BNP Brain natriuretic peptide, NA Not applicable with SARS-CoV-2-induced sepsis at ICU admission, while elevated inflammation-related parameters, C-reactive protein (CRP) as an example, were observed in this cohort compared to patients with bacterial sepsis. In addition, obvious differences in organ functional parameters were noted between the two cohorts, including significantly increased levels of creatine kinase-MB and NT-pro BNP, and decreased albumin level in patients with developed bacterial sepsis. In this study, ICU patients with SARS-CoV-2-induced sepsis and those with bacterial sepsis revealed comparable demographic characteristics, like age, gender distribution, and comorbidities, after rigorous screening processes. However, patients with bacterial sepsis were found with more severe organ dysfunction and poor outcomes when compared with those caused by SARS-CoV-2-induced sepsis, including higher values in SOFA and APACHE II, as well as more ICU deaths. The different patterns of immune responses might be the major cause of the divergent outcomes between viral and bacterial sepsis. We further found that failed homeostasis was characterized in both bacterial and viral sepsis but triggered by different pathogens. In the development of viral sepsis, the loss of T lymphocytes and their subsets was the dominant characteristics of dysregulated immune response, thereby contributing to the imbalance between innate and adaptive immune systems; while excessive inflammatory activation was the main feature of bacterial sepsis, which further resulted in intractable immune suppression and multiple organ dysfunction. This is the first report that compared clinical features and host responses between bacterial and SARS-CoV-2-induced viral sepsis. These findings might not only suggest divergent host responses to bacteria and virus but also provide novel insights into further researches on the development of sepsis with underlying etiology of various pathogens. Supplementary information accompanies this paper at https://doi.org/10. 1186/s40779-020-00267-3. Additional file 1. Appendix Table 1 . Baseline characteristics of critically ill patients with SARS-CoV-2-and bacteria-induced sepsis. Pathological findings of COVID-19 associated with acute respiratory distress syndrome The third international consensus definitions for sepsis and septic shock (Sepsis-3) SARS-CoV-2 and viral sepsis: observations and hypotheses Clinical features and development of sepsis in patients infected with SARS-CoV-2: a retrospective analysis of 150 cases outside Wuhan, China A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus (2019-nCoV) infected pneumonia (standard version) Not applicable. All corresponding and first authors contributed to the study concept and design. CR and RQY analyzed the data and drafted this letter. DR and YL recruited patients and extracted epidemiological and clinical data. All authors reviewed and approved the final manuscript. Availability of data and materials All data were presented in this manuscript or Appendix. This study was approved by the Committee on the Ethics of Medicine, the Second People's Hospital of Shenzhen, China (20200601026). Not applicable. We declare no competing interests.