Omicron Variants of the SARS-COV-2: A Potentially Significant Threat in a New Wave of Infections

From the beginning, the COVID-19 pandemic turned out to be a huge challenge and burden for medical services [1]. Currently, humanity is dealing with a new wave of the virus that has evolved and presents a new challenge, mainly due to its ability to avoid immune surveillance. Indeed, our main line of defense — vaccines — may be compromised. Omicron variants are characterized by an evolutionary force unprecedented so far. Among the several sublines that have already emerged, the BA.5 strain exhibit higher transmissibility and demonstrates a worrisome immune evasion. According to several laboratory investigations, vaccination-induced antibodies are less successful at preventing BA.4/5 strains infection as opposed to the infections following BA.1/BA.2 strains exposure [2–6]. The hyper contagious BA.5 variant is mainly responsible for the rise in hospital and intensive care unit utilization we are facing in the current times. Within a few months, BA.5 outperformed its forerunners and became the dominant strain in the United States (US). According to the most recent statistics provided by the Centers for Disease Control and Prevention (CDC), this subvariant was responsible for nearly 2 out of every 3 new COVID-19 infections in the US (3.07.2022–9.07.2022) [7]

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome associated with COVID-19: An Emulated Target Trial Analysis.

RATIONALE: Whether COVID patients may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. OBJECTIVES: To estimate the effect of ECMO on 90-Day mortality vs IMV only Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO vs. no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 <80 or PaCO2 ≥60 mmHg). We controlled for confounding using a multivariable Cox model based on predefined variables. MAIN RESULTS: 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability at Day-7 from the onset of eligibility criteria (87% vs 83%, risk difference: 4%, 95% CI 0;9%) which decreased during follow-up (survival at Day-90: 63% vs 65%, risk difference: -2%, 95% CI -10;5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand, and when initiated within the first 4 days of MV and in profoundly hypoxemic patients. CONCLUSIONS: In an emulated trial based on a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and in regions with ECMO capacities specifically organized to handle high demand. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Systematic review with meta-analysis of mid-regional pro-adrenomedullin (MR-proadm) as a prognostic marker in Covid-19-hospitalized patients

AbstractBackground Mid-regional pro-adrenomedullin (MR-proADM) is useful for risk stratification in patients with sepsis and respiratory infections. The study’s purpose was to assess the available data and determine the association between MR-proADM levels and mortality in COVID-19 participants.Methods A comprehensive literature search of medical electronic databases was performed including PubMed, Web of Science, Scopus, Cochrane, and grey literature for relevant data published from 1 January 2020, to 20 November 2022. Mean differences (MD) with 95% confidence intervals (CI) were calculated.Results Fourteen studies reported MR-proADM levels in survivors vs. non-survivors of COVID-19 patients. Pooled analysis showed that MR-proADM level in the survivor group was 0.841 ± 0.295 nmol/L for patients who survive COVID-19, compared to 1.692 ± 0.761 nmol/L for non-survivors (MD = −0.78; 95%CI: −0.92 to −0.64; p < 0.001).Conclusions The main finding of this study is that mortality of COVID-19 is linked to MR-proADM levels, according to this meta-analysis. The use of MR-proADM might be extremely beneficial in triaging, assessing probable therapy escalation, predicting potential complications during therapy or significant clinical deterioration of patients, and avoiding admission which may not be necessary. Nevertheless, in order to confirm the obtained data, it is necessary to conduct large prospective studies that will address the potential diagnostic role of MR-proADM as a marker of COVID-19 severity.KEY MESSAGESSeverity of COVID-19 seems to be linked to MR-proADM levels and can be used as a potential marker for predicting a patient’s clinical course.The use of MR-proADM might be beneficial in triaging, assessing probable therapy escalation, predicting potential complications during therapy or significant clinical deterioration of patients, and avoiding admission which may not be necessary.For patients with COVID-19, MR-proADM may be an excellent prognostic indicator because it is a marker of endothelial function that may predict the precise impact on the equilibrium between vascular relaxation and contraction and lowers platelet aggregation inhibitors, coagulation inhibitors, and fibrinolysis activators in favor of clotting factors

Pulmonary infections prime the development of subsequent ICU-acquired pneumonia in septic shock

Abstract Purpose To investigate the determinants and the prognosis of intensive care unit (ICU)-acquired pneumonia in patients with septic shock. Methods This single-center retrospective study was conducted in a medical ICU in a tertiary care center from January 2008 to December 2016. All consecutive patients diagnosed for septic shock within the first 48 h of ICU admission were included. Patients were classified in three groups: no ICU-acquired infections (no ICU-AI), ICU-acquired pneumonia and non-pulmonary ICU-AI. The determinants of ICU-acquired pneumonia and death were investigated by multivariate competitive risk analysis. Results A total of 1021 patients were admitted for septic shock, and 797 patients were alive in the ICU after 48 h of management. The incidence of a first episode of ICU-AI was 31%, distributed into pulmonary (17%) and non-pulmonary ICU-AI (14%). Patients with septic shock caused by pneumonia were at increased risk of further pulmonary ICU-AI with a cumulated incidence of 34.4%. A pulmonary source of the initial septic shock was an independent risk factor for subsequent ICU-acquired pneumonia (cause-specific hazard 2.33, 95% confidence interval [1.55–3.52], p < 0.001). ICU-AI were not associated with a higher risk of ICU mortality after adjustment in a multivariate-adjusted cause-specific proportional hazard model. Conclusion Septic shock of pulmonary origin may represent a risk factor for subsequent ICU-acquired pneumonia without affecting mortality

Comparison of Circulating Immune Cells Profiles and Kinetics Between Coronavirus Disease 2019 and Bacterial Sepsis*

International audienceObjectives: Although clinical presentation of coronavirus disease 2019 has been extensively described, immune response to severe acute respiratory syndrome coronavirus 2 remains yet not fully understood. Similarities with bacterial sepsis were observed; however, few studies specifically addressed differences of immune response between both conditions. Here, we report a longitudinal analysis of the immune response in coronavirus disease 2019 patients, its correlation with outcome, and comparison between severe coronavirus disease 2019 patients and septic patients.Design: Longitudinal, retrospective observational study.Setting: Tertiary-care hospital during the first 2020 coronavirus disease 2019 outbreak in France.Patients: All successive patients with confirmed severe acute respiratory syndrome coronavirus 2 infection admitted to the emergency department, medical ward, and ICU with at least one available immunophenotyping performed during hospital stay.Measurements and main results: Between March and April 2020, 247 patients with coronavirus disease 2019 were included and compared with a historical cohort of 108 severe septic patients. Nonsevere coronavirus disease 2019 patients (n = 153) presented normal or slightly altered immune profiles. Severe coronavirus disease 2019 (n = 94) immune profile differed from sepsis. Coronavirus disease 2019 exhibited profound and prolonged lymphopenia (mostly on CD3, CD4, CD8, and NK cells), neutrophilia, and human leukocyte antigen D receptor expression on CD14+ monocytes down-regulation. Surprisingly, coronavirus disease 2019 patients presented a unique profile of B cells expansion, basophilia, and eosinophilia. Lymphopenia, human leukocyte antigen D receptor expression on CD14+ monocytes down-regulation, and neutrophilia were associated with a worsened outcome, whereas basophilia and eosinophilia were associated with survival. Circulating immune cell kinetics differed between severe coronavirus disease 2019 and sepsis, lack of correction of immune alterations in coronavirus disease 2019 patients during the first 2 weeks of ICU admission was associated with death and nosocomial infections.Conclusions: Circulating immune cells profile differs between mild and severe coronavirus disease 2019 patients. Severe coronavirus disease 2019 is associated with a unique immune profile as compared with sepsis. Several immune features are associated with outcome. Thus, immune monitoring of coronavirus disease 2019 might be of help for patient management

Two New Neutrophil Subsets Define a Discriminating Sepsis Signature

International audienceRationale: Sepsis is the leading cause of death in adult ICUs. At present, sepsis diagnosis relies on nonspecific clinical features. It could transform clinical care to have immune-cell biomarkers that could predict sepsis diagnosis and guide treatment. For decades, neutrophil phenotypes have been studied in sepsis, but a diagnostic cell subset has yet to be identified.Objectives: To identify an early, specific immune signature of sepsis severity that does not overlap with other inflammatory biomarkers and that distinguishes patients with sepsis from those with noninfectious inflammatory syndrome.Methods: Mass cytometry combined with computational high-dimensional data analysis was used to measure 42 markers on whole-blood immune cells from patients with sepsis and control subjects and to automatically and comprehensively characterize circulating immune cells, which enables identification of novel, disease-specific cellular signatures.Measurements and Main Results: Unsupervised analysis of high-dimensional mass cytometry data characterized previously unappreciated heterogeneity within the CD64+ immature neutrophils and revealed two new subsets distinguished by CD123 and PD-L1 (programmed death ligand 1) expression. These immature neutrophils exhibited diminished activation and phagocytosis functions. The proportion of CD123-expressing neutrophils correlated with clinical severity.Conclusions: This study showed that these two new neutrophil subsets were specific to sepsis and detectable through routine flow cytometry by using seven markers. The demonstration here that a simple blood test distinguishes sepsis from other inflammatory conditions represents a key biological milestone that can be immediately translated into improvements in patient care