The dynamic changes of lymphocyte subsets and cytokines profiles of patients with novel coronavirus disease (COVID-19) and their correlation with the disease severity remain unclear. Peripheral blood samples were longitudinally collected from 40 confirmed COVID-19 patients and examined for lymphocyte subsets by flow cytometry and cytokine profiles by specific immunoassays. Of the 40 COVID-19 patients enrolled, 13 severe cases showed significant and sustained decreases in lymphocyte counts [0·6 (0·6-0·8)] but increases in neutrophil counts [4·7 (3·6-5·8)] than 27 mild cases [1.1 (0·8-1·4); 2·0 (1·5-2·9)]. Further analysis demonstrated significant decreases in the counts of T cells, especially CD8⁺ T cells, as well as increases in IL-6, IL-10, IL-2 and IFN-γ levels in the peripheral blood in the severe cases compared to those in the mild cases. T cell counts and cytokine levels in severe COVID-19 patients who survived the disease gradually recovered at later time points to levels that were comparable to those of the mild cases. Moreover, the neutrophil-to-lymphocyte ratio (NLR) (AUC=0·93) and neutrophil-to-CD8⁺ T cell ratio (N8R) (AUC =0·94) were identified as powerful prognostic factors affecting the prognosis for severe COVID-19. The degree of lymphopenia and a proinflammatory cytokine storm is higher in severe COVID-19 patients than in mild cases, and is associated with the disease severity. N8R and NLR may serve as a useful prognostic factor for early identification of severe COVID-19 cases. The National Natural Science Foundation of China, the National Science and Technology Major Project, the Health Commission of Hubei Province, Huazhong University of Science and Technology, and the Medical Faculty of the University Hospital Essen, Germany.

Background: The dynamic changes of lymphocyte subsets and cytokines profiles of patients with novel coronavirus disease (COVID-19) and their correlation with the disease severity remain unclear. Methods: Peripheral blood samples were longitudinally collected from 40 confirmed COVID-19 patients and examined for lymphocyte subsets by flow cytometry and cytokine profiles by specific immunoassays. Results: Of the 40 COVID-19 patients enrolled, 13 severe cases showed significant and sustained decreases in lymphocyte counts but increases in neutrophil counts than 27 mild cases. Further analysis demonstrated significant decreases in the counts of T cells, especially CD8 + T cells, as well as increases in IL-6, IL-10, IL-2 and IFN-γ levels in the peripheral blood in the severe cases compared to those in the mild cases. T cell counts and cytokine levels in severe COVID-19 patients who survived the disease gradually recovered at later time points to levels that were comparable to those of the mild cases. Moreover, the neutrophil-to-CD8+ T cell ratio (N8R) were identified as the most powerful prognostic factor affecting the prognosis for severe COVID-19. Conclusions: The degree of lymphopenia and a proinflammatory cytokine storm is higher in severe COVID-19 patients than in mild cases, and is associated with the disease severity. N8R may serve as a useful prognostic factor for early identification of severe COVID-19 cases. Summary: Lymphocyte subsets and cytokine profiles in the peripheral blood of COVID-19 patients were longitudinally characterized. The study revealed the kinetics features of immune parameters associated with the disease severity and identified N8R as a useful prognostic factor for predicting severe COVID-19 cases.

Background: Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) are the important pathogens causing pneumonia. This study aimed to investigate the clinical characteristics and molecular epidemiology of ESBL-producing E. coli and K. pneumoniae causing pneumonia at a large teaching hospital in China. Methods: We collected patient's clinical data and ESBL-producing E. coli and K. pneumoniae strains causing pneumonia (from December 2015 to June 2016) at a hospital in Wuhan. The susceptibilities, multi-locus sequence typing, homologous analysis, ESBL genes by polymerase chain reaction and sequencing were determined. Results: A total of 59 ESBL-producing strains (31 E. coli and 28 K. pneumoniae) isolated from patients with pneumonia were analyzed. The majority of strains were isolated from patients were with hospital-acquired pneumonia (37/59, 62.7%), followed by community-acquired pneumonia (13/59, 22.0%), and ventilator-related pneumonia (9/59, 15.3%). The E. coli ST131 (9 isolates, 29.0%) and K. pneumoniae ST11 (5 isolates, 17.9%) were the predominant sub-types. The most prevalent ESBL gene was CTX-M-14, followed by SHV-77, CTX-M-3, SHV-11, and CTX-M-27. At least 33 (55.9%) of the ESBL-producing strains carried two or more ESBL genes. The ISEcp1 and IS26 were found upstream of all blaCTX-M (CTX-Ms) and of most blaSHV (SHVs) (57.6%), respectively. Moreover, three ESBL-producing K. pneumoniae ST11 strains which were resistant to carbapenems carried the bla_NDM-1 and bla_KPC-2, two of which also bearing bla_OXA-48 were resistant to all antibiotics (including Tigecycline). Conclusions: Hospital-acquired pneumonia is more likely correlated with ESBL-producing E. coli and K. pneumoniae. ESBL-producing E. coli ST131 and multi-drug resistance ESBL-producing, as well as New Delhi metallo-β-lactamase-1 (NDM-1) and Klebsiella pneumoniae carbapenemases-2 (KPC-2) bearing K. pneumoniae ST11 are spreading in patients with pneumonia in hospital.

Liu J, et al. Yonsei Med J. 2020 Feb;61(2):145-153. https://doi.org/10.3349/ymj.2020.61.2.145

Background and Aims: Acute-on-chronic liver failure (ACLF) is a highly dynamic syndrome. The objective of this study was to delineate the clinical course of patients with HBV-ACLF and to develop a model to estimate the temporal evolution of disease severity. Methods: We enrolled eligible patients from 2 large, multicenter prospective cohorts. The ACLF grade, organ failures, and outcomes were assessed at multiple time points (days 1/4/7/14/21/28). Probabilities for ACLF transitions between these disease states and to death within 28 days were calculated using a multi-state model that used baseline information and updated ACLF status. The model was validated in independent patients. Results: Among all the 445 patients with HBV-ACLF, 76 represented disease progression, 195 had a stable or fluctuating course, 8 with improvement, and the remaining 166 with resolution within 28-day follow-up. New coagulation (63.64%) or renal failure (45.45%) was frequently observed during early progression. Patients with disease progression had a higher incidence of new episodes of ascites [10 (13.16%) vs. 22 (5.96%), p = 0.027] and HE [13(17.11%) vs. 21 (5.69%), p = 0.001], and a significant increase in white blood cell count. The multi-state model represented dynamic areas under the receiver operating characteristic curves ranging from 0.71 to 0.84 for predicting all ACLF states and death at 4, 7, 14, 21, and 28 days post-enrollment and from 0.73 to 0.94 for predicting death alone, performing better than traditional prognostic scores. Conclusions: HBV-ACLF is a highly dynamic syndrome with reversibility. The multi-state model is a tool to estimate the temporal evolution of disease severity, which may inform clinical decisions on treatment.

Acute-on-chronic liver failure (ACLF) is a severe clinical syndrome characterized by high morbidity and mortality rates. Bacterial infection is a frequent precipitating factor and complication in ACLF patients, significantly worsening patient outcomes. Elucidating the mechanisms underlying bacterial infections and their impact on ACLF pathophysiology is crucial for developing effective therapies to reduce infection rates and mortality. Current research highlights that immune suppression in ACLF increases susceptibility to bacterial infections, which in turn exacerbate immune dysfunction. However, a comprehensive review summarizing the emerging mechanisms underlying this immunosuppression is currently lacking. This review aims to provide an overview of the latest research, focusing on alterations in the immune responses of innate immune cells—including monocytes, macrophages, and neutrophils—as well as adaptive immune cells such as T and B lymphocytes during the onset and progression of bacterial infections in ACLF. In addition, recent advances in immunomodulatory therapies, including stem cell-based interventions, will also be discussed.