Epigenetic and transcriptomic reprogramming in monocytes of severe COVID-19 patients reflects alterations in myeloid differentiation and the influence of inflammatory cytokines.

BACKGROUND: COVID-19 manifests with a wide spectrum of clinical phenotypes, ranging from asymptomatic and mild to severe and critical. Severe and critical COVID-19 patients are characterized by marked changes in the myeloid compartment, especially monocytes. However, little is known about the epigenetic alterations that occur in these cells during hyperinflammatory responses in severe COVID-19 patients. METHODS: In this study, we obtained the DNA methylome and transcriptome of peripheral blood monocytes from severe COVID-19 patients. DNA samples extracted from CD14 + CD15- monocytes of 48 severe COVID-19 patients and 11 healthy controls were hybridized on MethylationEPIC BeadChip arrays. In parallel, single-cell transcriptomics of 10 severe COVID-19 patients were generated. CellPhoneDB was used to infer changes in the crosstalk between monocytes and other immune cell types. RESULTS: We observed DNA methylation changes in CpG sites associated with interferon-related genes and genes associated with antigen presentation, concordant with gene expression changes. These changes significantly overlapped with those occurring in bacterial sepsis, although specific DNA methylation alterations in genes specific to viral infection were also identified. We also found these alterations to comprise some of the DNA methylation changes occurring during myeloid differentiation and under the influence of inflammatory cytokines. A progression of DNA methylation alterations in relation to the Sequential Organ Failure Assessment (SOFA) score was found to be related to interferon-related genes and T-helper 1 cell cytokine production. CellPhoneDB analysis of the single-cell transcriptomes of other immune cell types suggested the existence of altered crosstalk between monocytes and other cell types like NK cells and regulatory T cells. CONCLUSION: Our findings show the occurrence of an epigenetic and transcriptional reprogramming of peripheral blood monocytes, which could be associated with the release of aberrant immature monocytes, increased systemic levels of pro-inflammatory cytokines, and changes in immune cell crosstalk in these patients.

Exposing and Overcoming Limitations of Clinical Laboratory Tests in COVID-19 by Adding Immunological Parameters; A Retrospective Cohort Analysis and Pilot Study.

Background: Two years since the onset of the COVID-19 pandemic no predictive algorithm has been generally adopted for clinical management and in most algorithms the contribution of laboratory variables is limited. Objectives: To measure the predictive performance of currently used clinical laboratory tests alone or combined with clinical variables and explore the predictive power of immunological tests adequate for clinical laboratories. Methods: Data from 2,600 COVID-19 patients of the first wave of the pandemic in the Barcelona area (exploratory cohort of 1,579, validation cohorts of 598 and 423 patients) including clinical parameters and laboratory tests were retrospectively collected. 28-day survival and maximal severity were the main outcomes considered in the multiparametric classical and machine learning statistical analysis. A pilot study was conducted in two subgroups (n=74 and n=41) measuring 17 cytokines and 27 lymphocyte phenotypes respectively. Findings: 1) Despite a strong association of clinical and laboratory variables with the outcomes in classical pairwise analysis, the contribution of laboratory tests to the combined prediction power was limited by redundancy. Laboratory variables reflected only two types of processes: inflammation and organ damage but none reflected the immune response, one major determinant of prognosis. 2) Eight of the thirty variables: age, comorbidity index, oxygen saturation to fraction of inspired oxygen ratio, neutrophil-lymphocyte ratio, C-reactive protein, aspartate aminotransferase/alanine aminotransferase ratio, fibrinogen, and glomerular filtration rate captured most of the combined statistical predictive power. 3) The interpretation of clinical and laboratory variables was moderately improved by grouping them in two categories i.e., inflammation related biomarkers and organ damage related biomarkers; Age and organ damage-related biomarker tests were the best predictors of survival, and inflammatory-related ones were the best predictors of severity. 4) The pilot study identified immunological tests (CXCL10, IL-6, IL-1RA and CCL2), that performed better than most currently used laboratory tests. Conclusions: Laboratory tests for clinical management of COVID 19 patients are valuable but limited predictors due to redundancy; this limitation could be overcome by adding immunological tests with independent predictive power. Understanding the limitations of tests in use would improve their interpretation and simplify clinical management but a systematic search for better immunological biomarkers is urgent and feasible.

Hemoadsorption for severe MIS-C in critically ill children, should we consider it as a therapeutic opportunity?

Multisystem inflammatory syndrome (MIS-C) is a new severe clinical condition that has emerged during the COVID-19 pandemic. MIS-C affects children and the young usually after a mild or asymptomatic COVID-19 infection. MIS-C has a high tropism for the cardiovascular system with need for inotropes and vasopressor support in 62% of cases. As of today a mortality from 1.5% to 1.9% related to MIS-C is reported. Hemoadsorption via the inflammatory mediator adsorber CytoSorb (CytoSorbents Europe, Berlin Germany) has been used as adjunctive therapy with the aim to restore the host response in septic shock and other hyper-inflammatory syndromes. We present the clinical experience of an adolescent boy with a refractory shock secondary to left ventricular dysfunction (LVD) in the context of MIS-C, treated with hemoadsorption, and continuous kidney replacement therapy (CKRT) in combination with immunomodulatory therapies. The therapeutic strategy resulted in hemodynamic and clinical stabilization as well as control of the hyperinflammatory response. Treatment appeared to be safe and feasible. Our findings are in line with previously published clinical cases on Cytosorb use in MIS-C showing the beneficial role of the hemoperfusion with Cytosorb in severe MIS-C to manage the cytokine storm. We provide an analysis and comparison of recent evidence on the use of hemoadsorption as an adjuvant therapy in critically ill children with severe forms of MIS-C, suggesting this blood purification strategy could be a therapeutic opportunity in severe LVD due to MIS-C, sparing the need for extracorporeal membrane oxygentation (ECMO) and other mechanical cardiocirculatory supports.

Blood purification in sepsis and COVID-19: what´s new in cytokine and endotoxin hemoadsorption.

Sepsis and COVID-19 are two clinical conditions that can lead to a dysregulated inflammatory state causing multiorgan dysfunction, hypercytokinemia, and a high risk of death. Specific subgroups of critically ill patients with particular characteristics could benefit from rescue treatment with hemoadsorption. There is a lack of adequately designed randomized controlled trials evaluating the potential benefits of cytokine or endotoxin hemoadsorption. Critically ill COVID-19 patients with severe acute respiratory failure poorly responsive to conventional treatment could be candidates to receive cytokine hemoadsorption in the presence of high levels of interleukin 6. This treatment can also be suitable for patients with refractory septic shock and hypercytokinemia. In the context of high endotoxin activity, hemoadsorption with polymyxin B could improve clinical parameters and the prognosis of patients with refractory septic shock. Predictive enrichment, using biomarkers or other individual features, identifies potential responders to cytokine, endotoxin, or sequential hemoadsorption. Besides, recognizing the particular subsets of patients likely to respond to one or both types of hemoadsorption will aid the design of future studies that accurately validate the effectiveness of these therapies.

Label-Free Plasmonic Biosensor for Rapid, Quantitative, and Highly Sensitive COVID-19 Serology: Implementation and Clinical Validation.

Serological tests are essential for the control and management of COVID-19 pandemic (diagnostics and surveillance, and epidemiological and immunity studies). We introduce a direct serological biosensor assay employing proprietary technology based on plasmonics, which offers rapid (<15 min) identification and quantification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in clinical samples, without signal amplification. The portable plasmonic device employs a custom-designed multiantigen (RBD peptide and N protein) sensor biochip and reaches detection limits in the low ng mL-1 range employing polyclonal antibodies. It has also been implemented employing the WHO-approved anti-SARS-CoV-2 immunoglobulin standard. A clinical validation with COVID-19 positive and negative samples (n = 120) demonstrates its excellent diagnostic sensitivity (99%) and specificity (100%). This positions our biosensor as an accurate and easy-to-use diagnostics tool for rapid and reliable COVID-19 serology to be employed both at laboratory and decentralized settings for the disease management and for the evaluation of immunological status during vaccination or treatment.

Planning for the assistance of critically ill patients in a Pandemic Situation: The experience of Vall d'Hebron University Hospital.

INTRODUCTION: In the context of community transmission of the virus, the impact of the pandemic on health-care systems, mainly on intensive care units (ICU), was expected to be devastating. Vall d'Hebron University Hospital (HUVH) implemented an unprecedented critical patient-care planning and management of resources. METHODS: We describe a cohort of critically ill patients during the first two months of the pandemic (from March 3, 2020, to May 2, 2020) in HUVH, Barcelona. In this manuscript, we report our previsions, strategies implemented, and the outcomes obtained. RESULTS: Three-thousand and thirty-three patients were admitted to the HUVH Critical Care Units. Throughout the study period, the proportion of patients on IMV or IMV and ECMO remained above 78%. Most patients were men (65%); the most common age group was 60-70 years. Twenty-three patients received ECMO, and eighteen were cannulated at another center and transferred to HUVH. At the end of the study, fourteen patients were successfully decannulated, three patients died, and the rest of the patients were still on ECMO. Eight pregnant women have been treated in the ICU, with a survival rate of 100%. The ICU mortality of patients younger than 60 years was 3.2%. The mean ICU stay of both survivors and nonsurvivors was 14 days. CONCLUSION: The adequate preparation for resource expansion for critically ill patients care, main challenges, and overall positive results can serve as a precedent for similar future scenarios.

The Use of CytoSorb Therapy in Critically Ill COVID-19 Patients: Review of the Rationale and Current Clinical Experiences.

The COVID-19 pandemic has led to the biggest global health crisis of our lifetime. There is accumulating evidence that a substantial number of critically ill COVID-19 patients exhibit a dysregulated host response manifesting as cytokine storm or cytokine release syndrome, which in turn contributes to the high observed rates of mortality. Just as in other hyperinflammatory conditions, extracorporeal cytokine removal may have potential beneficial effects in this subgroup of COVID-19 patients. The CytoSorb blood purification device is the most extensively investigated cytokine removal platform with considerable evidence suggesting that early intervention can provide rapid hemodynamic stabilization and improvement in vital organ functions. The purpose of this review is to provide an overview of the pathophysiological background of hyperinflammation in COVID-19 and to summarize the currently available evidence on the effects of hemoadsorption in these patients.

Hemadsorption as a Treatment Option for Multisystem Inflammatory Syndrome in Children Associated With COVID-19. A Case Report.

Multisystem Inflammatory Syndrome in Children (MIS-C) associated with COVID-19 is characterized by hypercytokinemia leading to overwhelming inflammation. We describe the use of a hemadsorption device as part of the supportive treatment for cytokine storm.

COVID-19 Infection in Critically Ill Patients Carries a High Risk of Venous Thrombo-embolism.

OBJECTIVE: The coronavirus disease of 2019 (COVID-19) due to SARS-CoV-2 infection has been found to cause an increased risk of venous thrombo-embolism (VTE). The aims of the study were to determine the frequency of VTE in critically ill patients with COVID-19 and its correlation with D dimer levels and pharmacological prophylaxis. METHODS: This was a cohort study of critically ill patients due to COVID-19. All patients admitted to the intensive care unit on the same day of April 2020 were selected, regardless of length of stay, and a single bilateral venous duplex ultrasound in the lower extremities was performed up to 72 hours later. Pulmonary embolism (PE) was diagnosed by computed tomography angiography. Asymptomatic and symptomatic VTE were registered, including pre-screening in hospital VTE. Characteristics of patients, blood test results, doses of thromboprophylaxis received, VTE events, and mortality after seven day follow up were recorded. RESULTS: A total of 230 critically ill patients were studied. The median intensive care unit stay of these patients was 12 days (interquartile range [IQR] 5 - 19 days). After seven days follow up, the frequency of patients with VTE, both symptomatic and asymptomatic, was 26.5% (95% confidence interval [CI] 21% - 32%) (69 events in 61 patients): 45 with DVT and 16 with PE (eight of them with concomitant DVT). The cumulative frequency of symptomatic VTE was 8.3% (95% CI 4.7% - 11.8%). D dimer values ≥ 1 500 ng/mL were diagnostic of VTE, with a sensitivity of 80% and a specificity of 42%. During follow up after screening, six patients developed new VTE. Three of them developed a recurrence after a DVT diagnosed at screening, despite receiving therapeutic doses of heparin. Mortality rates at seven day follow up were the same for those with (6.6%) and without (5.3%) VTE. CONCLUSION: Patients with severe COVID-19 infection are at high risk of VTE, and further new symptomatic VTE events and recurrence can occur despite anticoagulation. The prophylactic anticoagulant dose may need to be increased in patients with a low risk of bleeding.

Planning for the assistance of critically ill patients in a Pandemic Situation: The experience of Vall d'Hebron University Hospital. / Organización de la atención a pacientes críticos en situación de pandemia: Experiencia del Hospital Vall d'Hebron durante el brote de neumonía por SARS-CoV-2.

INTRODUCTION: In the context of community transmission of the virus, the impact of the pandemic on health-care systems, mainly on intensive care units (ICU), was expected to be devastating. Vall d́Hebron University Hospital (HUVH) implemented an unprecedented critical patient-care planning and management of resources. METHODS: We describe a cohort of critically ill patients during the first two months of the pandemic (from March 3, 2020, to May 2, 2020) in HUVH, Barcelona. In this manuscript, we report our previsions, strategies implemented, and the outcomes obtained. RESULTS: Three-thousand and thirty-three patients were admitted to the HUVH Critical Care Units. Throughout the study period, the proportion of patients on IMV or IMV and ECMO remained above 78%. Most patients were men (65%); the most common age group was 60-70 years. Twenty-three patients received ECMO, and eighteen were cannulated at another center and transferred to HUVH. At the end of the study, fourteen patients were successfully decannulated, three patients died, and the rest of the patients were still on ECMO. Eight pregnant women have been treated in the ICU, with a survival rate of 100%. The ICU mortality of patients younger than 60 years was 3.2%. The mean ICU stay of both survivors and nonsurvivors was 14 days. CONCLUSION: The adequate preparation for resource expansion for critically ill patients care, main challenges, and overall positive results can serve as a precedent for similar future scenarios.