Blood transcriptome responses in patients correlate with severity of COVID-19 disease

BackgroundCoronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Infected individuals display a wide spectrum of disease severity, as defined by the World Health Organization (WHO). One of the main factors underlying this heterogeneity is the host immune response, with severe COVID-19 often associated with a hyperinflammatory state.AimOur current study aimed to pinpoint the specific genes and pathways underlying differences in the disease spectrum and outcomes observed, through in-depth analyses of whole blood transcriptomics in a large cohort of COVID-19 participants.ResultsAll WHO severity levels were well represented and mild and severe disease displaying distinct gene expression profiles. WHO severity levels 1-4 were grouped as mild disease, and signatures from these participants were different from those with WHO severity levels 6-9 classified as severe disease. Severity level 5 (moderate cases) presented a unique transitional gene signature between severity levels 2-4 (mild/moderate) and 6-9 (severe) and hence might represent the turning point for better or worse disease outcome. Gene expression changes are very distinct when comparing mild/moderate or severe cases to healthy controls. In particular, we demonstrated the hallmark down-regulation of adaptive immune response pathways and activation of neutrophil pathways in severe compared to mild/moderate cases, as well as activation of blood coagulation pathways.ConclusionsOur data revealed discrete gene signatures associated with mild, moderate, and severe COVID-19 identifying valuable candidates for future biomarker discovery

Sepsis, septic shock and multiple organ dysfunction syndrome: selected cellular immune mechanisms and methodological aspects

SEPSIS, SEPTIC SHOCK AND MULTIPLE ORGAN DYSFUNCTION SYNDROME: SELECTED CELLULAR IMMUNE MECHANISMS AND METHODOLOGICAL ASPECTS MUDr. Thomas Karvunidis ABSTRACT Sepsis and septic shock with multiple organ dysfunction syndrome are frequent life-threatening conditions. Despite long-time scientific effort, their exact pathophysiology, causal treatment, and prevention remain obscure. The numbers of mediators and elements (e.g. leukocytes, thrombocytes, endothelium/microcirculation etc.) have been suggested as key mediators in the process of initiation and modulation of this dreadful disease. The aim of the thesis is to better describe and document the cellular mechanisms in the pathophysiology of sepsis, septic shock and multiple organ dysfunction syndrome using different analytic methods including microcirculation assessment, flowcytometry, and proteomics. The first original manuscript studied the role of neutrophils in the process of microcirculation impairment in septic shock patients, as a central pathophysiological mechanism of systemic inflammation. The real-time intravital videomicroscopy technique was used. This is the first clinical study reporting microvascular changes in septic shock patients with chemotherapy-induced cytopenia. The microcirculation injury was identical in cytopenic compared to..

Pathway and Network Analyses Identify Growth Factor Signaling and MMP9 as Potential Mediators of Mitochondrial Dysfunction in Severe COVID-19

Patients with preexisting metabolic disorders such as diabetes are at a higher risk of developing severe coronavirus disease 2019 (COVID-19). Mitochondrion, the very organelle that controls cellular metabolism, holds the key to understanding disease progression at the cellular level. Our current study aimed to understand how cellular metabolism contributes to COVID-19 outcomes. Metacore pathway enrichment analyses on differentially expressed genes (encoded by both mitochondrial and nuclear deoxyribonucleic acid (DNA)) involved in cellular metabolism, regulation of mitochondrial respiration and organization, and apoptosis, was performed on RNA sequencing (RNASeq) data from blood samples collected from healthy controls and patients with mild/moderate or severe COVID-19. Genes from the enriched pathways were analyzed by network analysis to uncover interactions among them and up- or downstream genes within each pathway. Compared to the mild/moderate COVID-19, the upregulation of a myriad of growth factor and cell cycle signaling pathways, with concomitant downregulation of interferon signaling pathways, were observed in the severe group. Matrix metallopeptidase 9 (MMP9) was found in five of the top 10 upregulated pathways, indicating its potential as therapeutic target against COVID-19. In summary, our data demonstrates aberrant activation of endocrine signaling in severe COVID-19, and its implication in immune and metabolic dysfunction

Diagnosis and outcome of acute respiratory failure in immunocompromised patients after bronchoscopy

Objective We wished to explore the use, diagnostic capability and outcomes of bronchoscopy added to noninvasive testing in immunocompromised patients. In this setting, an inability to identify the cause of acute hypoxaemic respiratory failure is associated with worse outcome. Every effort should be made to obtain a diagnosis, either with noninvasive testing alone or combined with bronchoscopy. However, our understanding of the risks and benefits of bronchoscopy remains uncertain. Patients and methods This was a pre-planned secondary analysis of Efraim, a prospective, multinational, observational study of 1611 immunocompromised patients with acute respiratory failure admitted to the intensive care unit (ICU). We compared patients with noninvasive testing only to those who had also received bronchoscopy by bivariate analysis and after propensity score matching. Results Bronchoscopy was performed in 618 (39%) patients who were more likely to have haematological malignancy and a higher severity of illness score. Bronchoscopy alone achieved a diagnosis in 165 patients (27% adjusted diagnostic yield). Bronchoscopy resulted in a management change in 236 patients (38% therapeutic yield). Bronchoscopy was associated with worsening of respiratory status in 69 (11%) patients. Bronchoscopy was associated with higher ICU (40% versus 28%; p\textless0.0001) and hospital mortality (49% versus 41%; p=0.003). The overall rate of undiagnosed causes was 13%. After propensity score matching, bronchoscopy remained associated with increased risk of hospital mortality (OR 1.41, 95% CI 1.08\textendash1.81). Conclusions Bronchoscopy was associated with improved diagnosis and changes in management, but also increased hospital mortality. Balancing risk and benefit in individualised cases should be investigated further

Long-term effects of restriction of intravenous fluid in adult ICU patients with septic shock

PURPOSE To assess long-term outcomes of restrictive versus standard intravenous (IV) fluid therapy in adult intensive care unit (ICU) patients with septic shock included in the European Conservative versus Liberal Approach to Fluid Therapy in Septic Shock in Intensive Care (CLASSIC) trial. METHODS We conducted the pre-planned analyses of mortality, health-related quality of life (HRQoL) using EuroQol (EQ)-5D-5L index values and EQ visual analogue scale (VAS), and cognitive function using Mini Montreal Cognitive Assessment (Mini MoCA) test at 1 year. Deceased patients were assigned numerical zero for HRQoL as a state equal to death and zero for cognitive function outcomes as worst possible score, and we used multiple imputation for missing data on HRQoL and cognitive function. RESULTS Among 1554 randomized patients, we obtained 1-year data on mortality in 97.9% of patients, HRQoL in 91.3%, and cognitive function in 86.3%. One-year mortality was 385/746 (51.3%) in the restrictive-fluid group versus 383/767 (49.9%) in the standard-fluid group, absolute risk difference 1.5%-points [99% confidence interval (CI) - 4.8 to 7.8]. Mean differences were 0.00 (99% CI - 0.06 to 0.05) for EQ-5D-5L index values, - 0.65 for EQ VAS (- 5.40 to 4.08), and - 0.14 for Mini MoCA (- 1.59 to 1.14) for the restrictive-fluid group versus the standard-fluid group. The results for survivors only were similar in both groups. CONCLUSIONS Among adult ICU patients with septic shock, restrictive versus standard IV fluid therapy resulted in similar survival, HRQoL, and cognitive function at 1 year, but clinically important differences could not be ruled out