Dear Editor,

The outbreak of novel coronavirus disease (COVID-19) that began in December 2019 has posed a great threat to human health and been declared a global pandemic by the World Health Organization [1,2,3]. Shenzhen, an important and special economic zone in China, shares a large floating population with Hubei province. From the first occurrence of COVID-19 on January 11, 2020, to April 26, 2020, there were 461 cases confirmed with infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including 12 patients who remained in the hospital, 3 deaths, and 446 discharged patients [4]. In the present study, we aimed to describe the clinical characteristics of COVID-19 patients in Shenzhen and identify risk factors for the development of SARS-CoV-2-induced sepsis in imported COVID-19 patients.

In this retrospective study, patients who were confirmed to have SARS-CoV-2 infection and admitted to the Third People’s Hospital of Shenzhen from January 11 to February 12, 2020, were enrolled. Clinical data were extracted and followed up to March 11, 2020, by using predesigned data collection forms. The baseline characteristics of all enrolled patients in the sepsis and non-sepsis groups were summarized and compared by applying Student’s t test, the Chi-square test, Fisher’s exact test, and the Mann–Whitney U test as appropriate. Continuous variables were presented as the mean (standard deviation [SD]) or median (interquartile range [IQR]), while categorical or ranked data were reported as counts and proportions.

A total of 150 hospitalized COVID-19 patients were enrolled in this study, including 49 (32.7%) patients with SARS-CoV-2-induced sepsis at hospital admission and 101 (67.3%) non-septic patients (Table 1). Patients with viral sepsis were much older than those without sepsis (63 vs. 46 years, P < 0.001) and presented with more comorbidities, including hypertension (14 [28.6%] vs. 11 [10.9%], P = 0.006) and diabetes (9 [18.4%] vs. 3 [3%], P = 0.003). Septic patients had significantly higher neutrophil counts, monocyte counts, international normalized ratios, D-dimer values, alanine aminotransferase, aspartate aminotransferase, serum creatinine, blood urea nitrogen, creatine kinase, lactate dehydrogenase, prothrombin times and activated partial thromboplastin times than non-septic patients, but their lymphocyte counts, platelet counts, and albumin levels were significantly lower. Septic patients were more likely to be transferred to the ICU (28 [57.1%] vs. 10 [9.9%]; P < 0.001) and had a significantly prolonged hospital stay (median days, 23.5 days [IQR, 16.3-32.8] vs. 15 days [IQR, 13-20]; P < 0.001) than non-septic patients. Additionally, deaths (3 [6.1%]) occurred solely among patients who developed sepsis at hospital admission. Exposure history, platelet count, T lymphocyte count, cytotoxic T lymphocyte count, IL-6, serum creatinine, erythrocyte sedimentation rate, and sodium might be useful for predicting the incidence of SARS-CoV-2-infection-induced sepsis (electronic supplementary materials).

Table 1 Baseline characteristics of 150 patients confirmed with COVID-19 in Shenzhen, China
Full size table

In conclusion, patients with SARS-CoV-2 infection are likely to develop sepsis at hospital admission, which are characterized by failed homeostasis between the innate and adaptive immune responses partly due to the loss of lymphocytes. The development of sepsis might be associated with greater organ dysfunction and worse outcomes in this small cohort of patients from Shenzhen.