Association Between Red Blood Cell Distribution Width and COVID-19 Severity in Delta Variant SARS-CoV-2 Infection

Indicators of stress hematopoiesis in the blood predict COVID-19 progression in patients over 65 years old

OBJECTIVES

Advanced age is a well-established risk factor for severe coronavirus disease 2019 (COVID-19). Exacerbated inflammation affects multiple organs, among which hematopoiesis responds by increased output of various cells. We aimed to determine the association between COVID-19 progression and large immature cell (LIC) counts, changes in erythrocyte and platelet distribution widths (RDW, PDW) with reference to patients' age.

METHODS

A total of 755 patients with complete blood cell (CBC) analysis in the first 24 h of hospitalization were enrolled. Patients were divided into two groups: under and above 65 years of age.

RESULTS

The LIC counts were different in both groups (p < 0.003). However, only the senior patients had markedly different values of RDW and PDW (p < 0.001). The receiver operating characteristic (ROC) curve analysis provided increased LIC (AUC = 0.600), RDW (AUC = 0.609), PDW (AUC = 0.556), and platelet to LIC ratio (AUC = 0.634) as significant in discriminating outcome in the older group. Importantly, these results were not repeated in the younger patients. In the elderly, the progression was predicted with LIC cut-off at ≥ 0.305 × 109/L (OR = 3.166) and RDW over 12.15% (OR = 2.081).

DISCUSSION

Aging is characterized by a decline in immunological competence with a compromised control of inflammation leading to a proinflammatory state. This background together with the actions of pathogens may lead to emergency myelopoiesis.

CONCLUSION

Our results point to the important differences between age groups regarding CBC-related parameters of stress hematopoiesis during severe infection. Higher LIC, RDW and PDW levels were reliable in the early identification of COVID-19 progression only in the elderly.

SARS-CoV-2 variants induce increased inflammatory gene expression but reduced interferon responses and heme synthesis as compared with wild type strains

SARS-CoV-2 variants of concern (VOC) have been associated with increased viral transmission and disease severity. We investigated the mechanisms of pathogenesis caused by variants using a host blood transcriptome profiling approach. We analysed transcriptional signatures of COVID-19 patients comparing those infected with wildtype (wt), alpha, delta or omicron strains seeking insights into infection in Asymptomatic cases.Comparison of transcriptional profiles of Symptomatic and Asymptomatic COVID-19 cases showed increased differentially regulated gene (DEGs) of inflammatory, apoptosis and blood coagulation pathways, with decreased T cell and Interferon stimulated genes (ISG) activation. Between SARS-CoV-2 strains, an increasing number of DEGs occurred in comparisons between wt and alpha (196), delta (1425) or, omicron (2313) infections. COVID-19 cases with alpha or, delta variants demonstrated suppression transcripts of innate immune pathways. EGR1 and CXCL8 were highly upregulated in those infected with VOC; heme biosynthetic pathway genes (ALAS2, HBB, HBG1, HBD9) and ISGs were downregulated. Delta and omicron infections upregulated ribosomal pathways, reflecting increased viral RNA translation. Asymptomatic COVID-19 cases infected with delta infections showed increased cytokines and ISGs expression. Overall, increased inflammation, with reduced host heme synthesis was associated with infections caused by VOC infections, with raised type I interferon in cases with less severe disease.

Immunohematologic Biomarkers in COVID-19: Insights into Pathogenesis, Prognosis, and Prevention

Coronavirus disease 2019 (COVID-19) has had profound effects on the health of individuals and on healthcare systems worldwide. While healthcare workers on the frontlines have fought to quell multiple waves of infection, the efforts of the larger research community have changed the arch of this pandemic as well. This review will focus on biomarker discovery and other efforts to identify features that predict outcomes, and in so doing, identify possible effector and passenger mechanisms of adverse outcomes. Identifying measurable soluble factors, cell-types, and clinical parameters that predict a patient's disease course will have a legacy for the study of immunologic responses, especially stimuli, which induce an overactive, yet ineffectual immune system. As prognostic biomarkers were identified, some have served to represent pathways of therapeutic interest in clinical trials. The pandemic conditions have created urgency for accelerated target identification and validation. Collectively, these COVID-19 studies of biomarkers, disease outcomes, and therapeutic efficacy have revealed that immunologic systems and responses to stimuli are more heterogeneous than previously assumed. Understanding the genetic and acquired features that mediate divergent immunologic outcomes in response to this global exposure is ongoing and will ultimately improve our preparedness for future pandemics, as well as impact preventive approaches to other immunologic diseases.

Risk Factors Related to the Death of Admitted COVID-19 Patients: A Buffalo Study

Background

Coronavirus disease 2019 (COVID-19) may result in a severe acute respiratory syndrome that leads to a worldwide pandemic. Despite the increasing understanding of COVID-19 disease, the mortality rate of hospitalized COVID-19 patients remains high.

Objective

To investigate the risk factors related to the mortality of admitted COVID-19 patients during the peak of the epidemic from August 2021 to October 2021 in Vietnam.

Methods

This is a prospective cohort study performed at the Hospital for Rehabilitation-Professional diseases. The baseline and demographic data, medical history, clinical examination, the laboratory results were recorded for patients admitted to the hospital with confirmed COVID-19. A radiologist and a pulmonologist will read the chest radiographs on admission and calculate the Brixia scores to classify the severity of lung abnormalities. Patients were followed up until beingrecovered or their death. Comparison of clinical and subclinical characteristics between recovery and death groups to find out risk factors related to the death of COVID-19 patients.

Results

Among 104 admitted COVID-19 patients, men accounted for 42.3%, average age of 61.7 ± 13.7. The most common symptoms were fever 76.9%, breathlessness 74%, and fatigue 53.8%. The majority (84.6%) of the study population had at least one co-morbidity, including hypertension (53.8%), diabetes (25.9%), gastritis (19.2%), ischemic heart disease (15.4) %), stroke (9.6%) and osteoarthritis (9.6%). The rate of mild and moderate COVID-19 is 13.4%, severe 32.7%, and critical 40.4%. There are 88 inpatients (84.6%) who needed respiratory support. The median hospital stay was 13 days (IQR 10-17.75 days). The rate of intubated patients with mechanical ventilation was 31.7%. The overall mortality rate was 29.8%. Risk factors related to death included Brixia scores > 9, Urea > 7 mmol/L, Ferrtin > 578 ng/ml, Failure to get vaccinated, Age > 60 years, and Low Oxygen SpO2 < 87% (BUFFALO).

Conclusion

The main result of the study is the independent risk factors related to the death of admitted COVID-19 patients including Brixia scores > 9, Urea > 7 mmol/L, Ferrtin > 578 ng/ml, Failure to get vaccinated, Age > 60 years, and Low Oxygen SpO2 < 87% ((BUFFALO) which suggests that these COVID-19 patients should be closely followed up.

Adverse Hematological Effects of COVID-19 Vaccination and Pathomechanisms of Low Acquired Immunity in Patients with Hematological Malignancies

The SARS-CoV-2 virus and the COVID-19 pandemic have spread across the world and severely impacted patients living with hematological conditions. Immunocompromised patients experience rapidly progressing symptoms following COVID-19 infection and are at high risk of death. In efforts to protect the vulnerable population, vaccination efforts have increased exponentially in the past 2 years. Although COVID-19 vaccination is safe and effective, mild to moderate side effects such as headache, fatigue, and soreness at the injection site have been reported. In addition, there are reports of rare side effects, including anaphylaxis, thrombosis with thrombocytopenia syndrome, Guillain-Barré Syndrome, myocarditis, and pericarditis after vaccination. Further, hematological abnormalities and a very low and transient response in patients with hematological conditions after vaccination raise concerns. The objective of this review is to first briefly discuss the hematological adverse effects associated with COVID-19 infection in general populations followed by critically analyzing the side effects and pathomechanisms of COVID-19 vaccination in immunocompromised patients with hematological and solid malignancies. We reviewed the published literature, with a focus on hematological abnormalities associated with COVID-19 infection followed by the hematological side effects of COVID-19 vaccination, and the mechanisms by which complications can occur. We extend this discussion to include the viability of vaccination efforts within immune-compromised patients. The primary aim is to provide clinicians with critical hematologic information on COVID-19 vaccination so that they can make informed decisions on how to protect their at-risk patients. The secondary goal is to clarify the adverse hematological effects associated with infection and vaccination within the general population to support continued vaccination within this group. There is a clear need to protect patients with hematological conditions from infection and modulate vaccine programs and procedures for these patients.

Increased IL-26 associates with markers of hyperinflammation and tissue damage in patients with acute COVID-19

Interleukin-26 (IL-26) is released by several immune and structural cells following stimulation of toll-like receptors (TLRs), whereupon it can directly inhibit viral replication and enhance neutrophil chemotaxis. Given these unique properties, IL-26 has emerged as an intriguing mediator of host defense in the lungs. However, the role of IL-26 in COVID-19 has not been thoroughly investigated. Here, we characterized the involvement of IL-26 in the hyperinflammation and tissue damage that occurs in patients with acute COVID-19. We found that IL-26 is markedly increased in blood samples from these patients, and that the concentration of IL-26 correlates with those of the neutrophil-mobilizing cytokines IL-8 and TNFα, respectively. Moreover, the increase in blood IL-26 correlates with enhanced surface expression of the “don’t eat me” signal CD47 on blood neutrophils isolated from patients with acute COVID-19. Finally, we found that the blood concentration of IL-26 correlates with that of increased lactate dehydrogenase, an established marker of tissue damage, and decreased mean corpuscular hemoglobin (MCH), a previously verified hematological aberration in COVID-19, both of which are associated with severe disease. Thus, our findings indicate that increased systemic IL-26 associates with markers of hyperinflammation and tissue damage in patients with acute COVID-19, thereby forwarding the kinocidin IL-26 as a potential target for diagnosis, monitoring, and therapy in this deadly disease.

Platelet-derived immuno-inflammatory indices show best performance in early prediction of COVID-19 progression

BACKGROUND

Coronavirus disease 2019 (COVID-19) profoundly affects the immune and hematopoietic systems with various degrees of reactive changes in the blood cell counts. Immuno-inflammatory indices are considered a simple and effective tool in the prediction of COVID-19 outcomes. We aimed to evaluate and compare the usefulness of leukocyte and platelet counts-based immuno-inflammatory indices on admission to hospital in predicting COVID-19 progression and mortality.

METHODS

A total of 945 patients were enrolled. In addition to blood cell counts, we assessed hemogram-derived immuno-inflammatory indices in relation to COVID-19 progression and death. The indices were tested by analysis of variance, receiver operating characteristic curve analysis, and binomial logistic regressions.

RESULTS

Patients with severe COVID-19 had significantly higher counts of neutrophils, eosinophils, and large immature cells (LIC), while decreased counts of platelets and monocytes. Lymphopenia was found in all of the patients, but without significant association with the outcomes. Patients with a LIC count ≥0.265 x 09 /L had 54.7% more odds of having COVID-19 progression. In multivariable analyses, platelets/neutrophil-to-lymphocyte ratio (P/NLR) and platelets-to-neutrophil radio (P/N) were significant independent predictors of COVID-19 progression and mortality. The odds of a poor outcome were two times higher in cases with P/NLR < 43 x 109 /L and P/N < 29 x 109 /L.

CONCLUSION

Indices that include platelet count in combination with neutrophil and/or lymphocyte counts displayed the best discriminatory ability and prognostic value of COVID-19 outcomes. Additionally, LIC showed promising results in the early identification of severe COVID-19.

Clinical Characteristics of COVID-19 Patients Infected by the Omicron Variant of SARS-CoV-2

Background

Currently, as the omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surges amid the coronavirus disease 2019 (COVID-19) pandemic, its clinical characteristics with intrinsic severity and the protection from vaccination have been understudied.

Methods

We reported 169 COVID-19 patients that were infected with the omicron variant of SARS-CoV-2 and hospitalized in Suzhou, China, from February to March 2022, with their demographic information, medical/immunization history, clinical symptom, and hematological profile. At the same time, patients with none/partial (one-dose), full (two-dose) and three-dose vaccination were also compared to assess the vaccine effectiveness.

Findings

For the omicron COVID-19 patients included in this study, their median age was 33.0 [interquartile range (IQR): 24.0-45.5], 53.3% were male and the median duration from illness onset to hospitalization was 2 days. Hypertension, bronchitis, and diabetes were the leading comorbidities among patients. While the common clinical symptoms included cough, fever, expectoration, and fatigue, etc., asymptomatic patients took up a significant portion (46.7%). For hematological parameters, most values revealed the alleviated pathogenicity induced by the omicron variant infection. No critically ill or deceased patients due to COVID-19 infection were reported in this study.

Interpretation

Our results supported that the viremic effect of the omicron variant became milder than the previous circulating variants, while full vaccination or booster shot was greatly desired for an effective protection against clinical severity.