Neutrophil to CD4+ lymphocyte ratio as a potential biomarker in predicting virus negative conversion time in COVID-19

Prognostic Value of Neutrophil-to-Lymphocyte Ratio and Vaccination for Negative Conversion Time of Nucleic Acid in Nonsevere COVID-19 Patients Infected by SARS-CoV-2 Omicron Variant

SARS-CoV-2 Omicron variant is significantly different from all the previous variants and has rapidly replaced other variants as the dominant variant across the globe. An easily obtained, inexpensive, and rapid marker is needed to predict the negative conversion time (NCT) of nucleic acid in nonsevere COVID-19 patients infected by the Omicron variant. This retrospective study enrolled 226 patients infected by the Omicron variant between April 23, 2022, and May 16, 2022. The median age of the patients was 61 (interquartile range (IQR), 48-70) years, and 56.2% were male. 84 patients (37.2%) had at least one comorbidity, and 49 patients (21.7%) were classified into the moderate illness group. 145 patients (64.2%) received at least one dose of vaccine, in which 67 patients (29.6%) received a booster dose of vaccine. The median duration of NCT was 8 (IQR, 7-11) days. Univariate Cox analyses found that high NLR (>2.22), aged ≥65 years, vaccination, and moderate illness were significantly related to the NCT of nucleic acid. Multivariate Cox regression analysis showed that high NLR (NLR > 2.22, hazard ratio (HR):0.718, 95% CI: 0.534-0.964, p = 0.028) and vaccination (vaccinated ≥1 dose, HR: 1.536, 95% CI: 1.147-2.058, p = 0.004) were independently associated with NCT of nucleic acid. NLR is a rapid, simple, and useful prognostic factor for predicting NCT of nucleic acid in nonsevere COVID-19 patients with the Omicron variant. In addition, vaccination may also play a valuable role in predicting the NCT of nucleic acid.

Coagulation Disorders in Sepsis and COVID-19-Two Sides of the Same Coin? A Review of Inflammation-Coagulation Crosstalk in Bacterial Sepsis and COVID-19

Sepsis is a major cause of morbidity and mortality worldwide. Sepsis-associated coagulation disorders are involved in the pathogenesis of multiorgan failure and lead to a subsequently worsening prognosis. Alongside the global impact of the COVID-19 pandemic, a great number of research papers have focused on SARS-CoV-2 pathogenesis and treatment. Significant progress has been made in this regard and coagulation disturbances were once again found to underlie some of the most serious adverse outcomes of SARS-CoV-2 infection, such as acute lung injury and multiorgan dysfunction. In the attempt of untangling the mechanisms behind COVID-19-associated coagulopathy (CAC), a series of similarities with sepsis-induced coagulopathy (SIC) became apparent. Whether they are, in fact, the same disease has not been established yet. The clinical picture of CAC shows the unique feature of an initial phase of intravascular coagulation confined to the respiratory system. Only later on, patients can develop a clinically significant form of systemic coagulopathy, possibly with a consumptive pattern, but, unlike SIC, it is not a key feature. Deepening our understanding of CAC pathogenesis has to remain a major goal for the research community, in order to design and validate accurate definitions and classification criteria.

Could serum thrombocyte/lymphocyte (TLR), neutrophil/lymphocyte (NLR) and neutrophil/albumin (NAR) ratios be indicators of hospitalization and mortality in COVID-19?

Background and Objectives

Neutrophil / lymphocyte (NLR) and thrombocyte / lymphocyte ratios (TLR) are also a guiding factors in the prognostic evaluation of infectious diseases. Another parameter to determine inflammation and prognosis is albumin. This study was aimed to determine whether TLR, NLR and neutrophil / albumin ratios (NAR) are effective in predicting the severity and course of Corona Virus Disease-2019 (COVID-19).

Materials and Methods

In this retrospective and cross-sectional study, a total of 1597 patients who were admitted to our hospital between 15.03.2020-1.06.2020, diagnosed with COVID-19 were evaluated.

Results

In the estimation of the decision for hospitalization, TLR, NLR and NAR AUROC values were 0.596, 0.634, 0.602 for cutoff values 123.7, 2.3 and 839.5, respectively. In predicting mortality, TLR, NLR and NAR AURO sample size can be specified C values were 0.674, 0.821, 0.787 for cutoff values 168.1, 5.2 and 1303.4, respectively (p <0.001 for all).

Conclusion

In our study, it was determined that TLR, NLR and NAR are independent predictors in making the decision of hospitalization and in determining the prognosis in patients who are decided to be hospitalized.

Immune response induced by novel coronavirus infection

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus (SARS-CoV)-2 has been prominent around the world since it was first discovered, affecting more than 100 million people. Although the symptoms of most infected patients are not serious, there is still a considerable proportion of patients who need hospitalization and even develop fatal symptoms such as cytokine storms, acute respiratory distress syndrome and so on. Cytokine storm is usually described as a collection of clinical manifestations caused by overactivation of the immune system, which plays an important role in tissue injury and multiorgan failure. The immune system of healthy individuals is composed of two interrelated parts, the innate immune system and the adaptive immune system. Innate immunity is the body's first line of defense against viruses; it can quickly perceive viruses through pattern recognition receptors and activate related inflammatory pathways to clear pathogens. The adaptive immune system is activated by specific antigens and is mainly composed of CD4+ T cells, CD8+ T cells and B cells, which play different roles in viral infection. Here, we discuss the immune response after SARS-CoV-2 infection. In-depth study of the recognition of and response of innate immunity and adaptive immunity to SARS-CoV-2 will help to prevent the development of critical cases and aid the exploration of more targeted treatments.

D-dimer levels and characteristics of lymphocyte subsets, cytokine profiles in peripheral blood of patients with severe COVID-19: A systematic review and meta-analysis

Purpose

A series of complications caused by severe COVID-19 can significantly affect short-term results. Therefore, early diagnosis is essential for critically COVID-19 patients. we aimed to investigate the correlation among D-dimer levels, lymphocyte subsets, cytokines, and disease severity in COVID-19 patients.

Methods

Systematic review and meta- analysis of PubMed, Scopus, Web of Science, Cochrane Central Register of Controlled Trials, Embase, clinical trials, and China National Knowledge Infrastructure (CNKI) until 1 August 2022. We considered case-control, and cohort studies that compared laboratory parameters between patients with severe or non-serious diseases or between survivors and non-survivors. Pooled data was assessed by use of a random-effects model and used I 2 to test heterogeneity. We assessed the risk of bias using the Newcastle- Ottawa Scale.

Results

Of the 5,561 identified studies, 32 were eligible and included in our analysis (N = 3,337 participants). Random-effect results indicated that patients with COVID-19 in severe group had higher levels for D-dimer (WMD = 1.217 mg/L, 95%CI=[0.788, 1.646], P < 0.001), neutrophil-to-lymphocyte ratio (NLR) (WMD = 6.939, 95%CI = [4.581, 9.297], P < 0.001), IL-2 (WMD = 0.371 pg/ml, 95%CI = [-0.190, 0.932], P = 0.004), IL-4 (WMD = 0.139 pg/ml, 95%CI = [0.060, 0.219], P = 0.717), IL-6 (WMD = 44.251 pg/ml, 95%CI = [27.010, 61.493], P < 0.001), IL-10 (WMD = 3.718 pg/ml, 95%CI = [2.648, 4.788], P < 0.001) as well as lower levels of lymphocytes (WMD = -0.468( × 109/L), 95%CI = [-0.543, -0.394], P < 0.001), T cells (WMD = -446.746(/μL), 95%CI = [-619.607, -273.885], P < 0.001), B cells (WMD = -60.616(/μL), 95%CI = [-96.452, -24.780], P < 0.001), NK cells (WMD = -68.297(/μL), 95%CI = [-90.600, -45.994], P < 0.001), CD3+T cells (WMD = -487.870(/μL), 95%CI = [-627.248, -348.492], P < 0.001), CD4+T cells (WMD = -290.134(/μL), 95%CI = [-370.834, -209.435], P < 0.001), CD8+T cells (WMD = -188.781(/μL), 95%CI = [-227.806, -149.757], P < 0.001).

Conclusions

There is a correlation among higher levels of D-dimer, cytokines, lower levels of lymphocyte subsets, and disease severity in COVID-19 patients. These effective biomarkers may help clinicians to evaluate the severity and prognosis of COVID-19. This study is registered with PROSPERO, number CRD42020196659.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=196659; PROSPERO registration number: CRD42020196659.

Duration of SARS-CoV-2 RNA positivity from various specimens and clinical characteristics in patients with COVID-19: a systematic review and meta-analysis

BACKGROUND

The duration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA positivity will be important to prevent the spread of coronavirus disease 2019 (COVID-19). A systematic review and meta-analysis were conducted following PRISMA to determine the duration from several parts of the body and clinical characteristics affecting it.

MAIN TEXT

PubMed, Web of Science, Scopus, and CENTRAL were searched for original studies reporting the duration from COVID-19 onset to the disappearance of viral RNA. Of the 1682 studies identified, 100 met the selection criteria and 13,431 patients were included in this study. The duration of SARS-CoV-2 RNA positivity was 18.29 [95% confidence interval: 17.00-19.89] days in the upper respiratory tract samples, 23.79 [20.43-27.16] days in the sputum, 14.60 [12.16-17.05] days in the blood, and 22.38 [18.40-26.35] days in the stool. Sensitivity analysis revealed that the duration was positively correlated with age, comorbidities, severity, and usage of glucocorticoid. Subgroup analysis indicated that the presence or absence of complications had the greatest impact on the difference in DSRP.

CONCLUSIONS

The duration of SARS-CoV-2 RNA positivity was 18.29 days in the upper respiratory tract samples. The duration in the sputum and the stool was longer, while that in the blood was shorter. The duration in the upper respiratory tract samples was longer in older, with any comorbidities, severer, and treated with glucocorticoid. These results provide the basic data for the duration of SARS-CoV-2 RNA positivity, and in the future, the effect of vaccination against SARS-CoV-2 and the SARS-CoV-2 variants on the duration of RNA positivity should be assessed.

Insights into the Role of Neutrophils and Neutrophil Extracellular Traps in Causing Cardiovascular Complications in Patients with COVID-19: A Systematic Review

Background: The coronavirus disease 2019 (COVID-19) pandemic caused by the SARS-CoV-2 virus has resulted in significant mortality and burdening of healthcare resources. While initially noted as a pulmonary pathology, subsequent studies later identified cardiovascular involvement with high mortalities reported in specific cohorts of patients. While cardiovascular comorbidities were identified early on, the exact manifestation and etiopathology of the infection remained elusive. This systematic review aims to investigate the role of inflammatory pathways, highlighting several culprits including neutrophil extracellular traps (NETs) which have since been extensively investigated. Method: A search was conducted using three databases (MEDLINE; MEDLINE In-Process & Other Non-Indexed Citations and EMBASE). Data from randomized controlled trials (RCT), prospective series, meta-analyses, and unmatched observational studies were considered for the processing of the algorithm and treatment of inflammatory response during SARS-CoV-2 infection. Studies without the SARS-CoV-2 Infection period and case reports were excluded. Results: A total of 47 studies were included in this study. The role of the acute inflammatory response in the propagation of the systemic inflammatory sequelae of the disease plays a major part in determining outcomes. Some of the mechanisms of activation of these pathways have been highlighted in previous studies and are highlighted. Conclusion: NETs play a pivotal role in the pathogenesis of the inflammatory response. Despite moving into the endemic phase of the disease in most countries, COVID-19 remains an entity that has not been fully understood with long-term effects remaining uncertain and requiring ongoing monitoring and research.

NETosis and Neutrophil Extracellular Traps in COVID-19: Immunothrombosis and Beyond

Infection with SARS-CoV-2, the causative agent of the Coronavirus disease 2019 (COVID-19) pandemic, causes respiratory problems and multifaceted organ dysfunction. A crucial mechanism of COVID-19 immunopathy is the recruitment and activation of neutrophils at the infection site, which also predicts disease severity and poor outcomes. The release of neutrophil extracellular traps (NETs), occurring during a regulated form of neutrophil cell death known as NETosis, is a key effector function that mediates harmful effects caused by neutrophils. Abundant NETosis and NET generation have been observed in the neutrophils of many COVID-19 patients, leading to unfavorable coagulopathy and immunothrombosis. Moreover, excessive NETosis and NET generation are now more widely recognized as mediators of additional pathophysiological abnormalities following SARS-CoV-2 infection. In this minireview, we introduce subtypes of NET-producing neutrophils (e.g., low-density granulocytes) and explain the biological importance of NETs and the protein cargos of NETs in COVID-19. In addition, we discuss the mechanisms by which SARS-CoV-2 causes NETosis by upregulating viral processes (e.g., viral entry and replication) as well as host pro-NET mechanisms (e.g., proinflammatory mediator release, platelet activation, and autoantibody production). Furthermore, we provide an update of the main findings of NETosis and NETs in immunothrombosis and other COVID-19-related disorders, such as aberrant immunity, neurological disorders, and post COVID-19 syndromes including lung fibrosis, neurological disorder, tumor progression, and deteriorated chronic illness. Finally, we address potential prospective COVID-19 treatment strategies that target dysregulated NETosis and NET formation via inhibition of NETosis and promotion of NET degradation, respectively.

Pathological effects of SARS-CoV-2 on hematological and immunological cells: Alterations in count, morphology, and function

The novel Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), the causative agent of COVID-19 outbreak, spread rapidly and infected more than 140 million people with more than three million victims worldwide. The SARS-CoV-2 causes destructive changes in the immunological and hematological system of the host. These alterations appear to play a critical role in disease pathology and the emerging of clinical manifestations. In this review, we aimed to discuss the effect of COVID-19 on the count, function and morphology of immune and blood cells and the role of these changes in the pathophysiology of the disease. Knowledge of these changes may help with better management and treatment of COVID-19 patients.

Spectrum of hematological changes in COVID-19

Coronavirus disease 2019 (COVID-19) is caused by pathogenic and highly transmissible Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which is a single stranded RNA virus. It rapidly emerged from an epidemic to a global pandemic form spreading in alarming levels. The pathogenesis involving spike protein which is present on the viral surface, plays a key role in host attachment and penetration. SARS-CoV-2 infection significantly affects respiratory system, but may involve other systems including haematopoietic system and homeostasis. Aim of the review article is to discuss spectrum of haematological changes in the blood counts, coagulation, peripheral blood and bone marrow in COVID-19 for complete understanding the disease process, the knowledge of which is helpful in early diagnosis and management of these patients. An extensive immune profiling of B and T cell population with analysis of spectrum of immune changes during the period of infection were also discussed. In COVID-19, changes in laboratory parameters and hematologic abnormalities have been reported and its association with early diagnosis, disease prognosis and severity has been repeatedly discussed in the literature. Changes in laboratory investigations help in risk stratification and early intervention. The most common laboratory finding in COVID-19 is lymphopenia. COVID-19 patients presented with coagulopathy is at high risk of morbidity and mortality. In severe COVID-19 patients, bone marrow aspirate shows histiocytic proliferation with hemophagocytosis. To understand the correlations between immune responses and severity of COVID-19, immune profiling of B and T cell population was compared with extensive clinical data. A deep understanding of the laboratory findings and haematological abnormalities associated with SARS-CoV-2 infection would help to raise disease suspicion in absence of Real time polymerase chain reaction or antibody results. Also the blood counts along with the morphological changes in peripheral blood would be helpful in prompt screening, diagnosis, prognosis and management of COVID-19 patients.

Risk factors for prolonged nucleic acid conversion time in patients with COVID-19

OBJECTIVES

The time for PCR positivity to negativity is defined as nucleic acid conversion time (NCT) and is very important in terminating the isolation of patients and determining infectiousness in patients with COVID-19. The aim of this study is to determine the median NCT and to evaluate the clinical and laboratory parameters affecting it in patients with COVID-19.

METHODS

This study included 318 patients with mild to moderate COVID-19 diagnosed with PCR positivity retrospectively.

RESULTS

The median NCT was 11 days. Patients were divided into 2 groups as early (<11 days) and late conversion (≥11 days). Older age, sore throat, onset fever, fever 72 h after hospitalization, history of exposure to SARS-CoV-2 virus without a mask, and moderated disease were significantly more common in the late conversion group. In addition, favipiravir use was higher in early conversion group and hydroxychloroquine use was higher in late conversion group. In multivariate analysis, sore throat (OR = 2.570; 95% CI: 1.051-6.284, P = 0.039) and hydroxychloroquine use (OR = 3.518, 95% CI: 1.163-10.635, P = 0,026) were independent risk factors for late conversion. Favipiravir use (OR = 0.062, 95% CI: 0.021-0.184, P = 0.0001) negatively affected the late conversion.

CONCLUSION

NCT was longer in patients with COVID-19 who had sore throat at admission and were treated with hydroxychloroquine instead of favipiravir.

Risk factors for oxygen requirement in hospitalized pregnant and postpartum women with COVID-19

OBJECTIVE

To identify risk factors for Oxygen (O₂) needs in pregnant and postpartum women with COVID-19.

METHODS

Prospective cohort involving pregnant women hospitalized with COVID-19 from April to October 2020. The oxygen need was analyzed regarding risk factors: demographic characteristics, clinical and laboratory parameters at hospital admission, and chest Computer Tomography (CT) findings. Poisson univariate analysis was used to estimate the Relative Risk (RR) and 95% Confidence Intervals.

RESULTS

145 patients, 80 who used and 65 who did not use O₂, were included. Body mass index ≥ 30, smoking, and chronic hypertension increased the risk of O₂ need by 1.86 (95% CI 1.10-3.21), 1.57 (95% CI 1.16‒2.12), and 1.46 (95% CI 1.09‒1.95), respectively. Patients who were hospitalized for COVID-19 and for obstetric reasons had 8.24 (95% CI 2.8‒24.29) and 3.44 (95% CI 1.05‒11.31) times more use of O₂ than those admitted for childbirth and abortion. Respiratory rate ≥ 24 breaths/min and O₂ saturation < 95% presented RR for O₂ requirements of 2.55 (1.82‒3.56) and 1.68 (95% CI 1.27-2.20), respectively. Ground Glass (GG) < 50% and with GG ≥ 50%, the risk of O₂ use were respectively 3.41-fold and 5.33-fold higher than in patients who haven't viral pneumonia on CT. The combination of C-reactive protein ≥ 21 mg/L, hemoglobin < 11.0 g/dL, and lymphopenia < 1500 mm³ on hospital admission increased the risk of O₂ use by 4.97-times.

CONCLUSIONS

In obstetric patients, clinical history, laboratory, clinical and radiological parameters at admission were identified as a risk for O₂ need, selecting the population with the greatest chance of worsening.

Role of Neutrophil Extracellular Traps in COVID-19 Progression: An Insight for Effective Treatment

The coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, has resulted in a pandemic with over 270 million confirmed cases and 5.3 million deaths worldwide. In some cases, the infection leads to acute respiratory distress syndrome (ARDS), which is triggered by a cytokine storm and multiple organ failure. Clinical hematological, biochemical, coagulation, and inflammatory markers, such as interleukins, are associated with COVID-19 disease progression. In this regard, neutrophilia, neutrophil-to-lymphocyte ratio (NLR), and neutrophil-to-albumin ratio (NAR), have emerged as promising biomarkers of disease severity and progression. In the pathophysiology of ARDS, the inflammatory environment induces neutrophil influx and activation in the lungs, promoting the release of cytokines, proteases, reactive oxygen species (ROS), and, eventually, neutrophil extracellular traps (NETs). NETs components, such as DNA, histones, myeloperoxidase, and elastase, may exert cytotoxic activity and alveolar damage. Thus, NETs have also been described as potential biomarkers of COVID-19 prognosis. Several studies have demonstrated that NETs are induced in COVID-19 patients, and that the highest levels of NETs are found in critical ones, therefore highlighting a correlation between NETs and severity of the disease. Knowledge of NETs signaling pathways, and the targeting of points of NETs release, could help to develop an effective treatment for COVID-19, and specifically for severe cases, which would help to manage the pandemic.

The Roles of Neutrophils in Cytokine Storms

A cytokine storm is an abnormal discharge of soluble mediators following an inappropriate inflammatory response that leads to immunopathological events. Cytokine storms can occur after severe infections as well as in non-infectious situations where inflammatory cytokine responses are initiated, then exaggerated, but fail to return to homeostasis. Neutrophils, macrophages, mast cells, and natural killer cells are among the innate leukocytes that contribute to the pathogenesis of cytokine storms. Neutrophils participate as mediators of inflammation and have roles in promoting homeostatic conditions following pathological inflammation. This review highlights the advances in understanding the mechanisms governing neutrophilic inflammation against viral and bacterial pathogens, in cancers, and in autoimmune diseases, and how neutrophils could influence the development of cytokine storm syndromes. Evidence for the destructive potential of neutrophils in their capacity to contribute to the onset of cytokine storm syndromes is presented across a multitude of clinical scenarios. Further, a variety of potential therapeutic strategies that target neutrophils are discussed in the context of suppressing multiple inflammatory conditions.

A hitchhiker's guide through the COVID-19 galaxy

Numerous reviews have summarized the epidemiology, pathophysiology and the various therapeutic aspects of Coronavirus disease 2019 (COVID-19), but a practical guide on "how to treat whom with what and when" based on an understanding of the immunological background of the disease stages remains missing. This review attempts to combine the current knowledge about the immunopathology of COVID-19 with published evidence of available and emerging treatment options. We recognize that the information about COVID-19 and its treatment is rapidly changing, but hope that this guide offers those on the frontline of this pandemic an understanding of the host response in COVID-19 patients and supports their ongoing efforts to select the best treatments tailored to their patient's clinical status.

Peripheral T cell lymphopenia in COVID-19: potential mechanisms and impact

Immunopathogenesis involving T lymphocytes, which play a key role in defence against viral infection, could contribute to the spectrum of COVID-19 disease and provide an avenue for treatment. To address this question, a review of clinical observational studies and autopsy data in English and Chinese languages was conducted with a search of registered clinical trials. Peripheral lymphopenia affecting CD4 and CD8 T cells was a striking feature of severe COVID-19 compared with non-severe disease. Autopsy data demonstrated infiltration of T cells into organs, particularly the lung. Seventy-four clinical trials are on-going that could target T cell-related pathogenesis, particularly IL-6 pathways. SARS-CoV-2 infection interrupts T cell circulation in patients with severe COVID-19. This could be due to redistribution of T cells into infected organs, activation induced exhaustion, apoptosis, or pyroptosis. Measuring T cell dynamics during COVID-19 will inform clinical risk-stratification of hospitalised patients and could identify those who would benefit most from treatments that target T cells.

He-Jie-Shen-Shi Decoction as an Adjuvant Therapy on Severe Coronavirus Disease 2019: A Retrospective Cohort and Potential Mechanistic Study

Combination therapy using Western and traditional Chinese medicines has shown notable effects on coronavirus disease 2019 (COVID-19). The He-Jie-Shen-Shi decoction (HJSS), composed of Bupleurum chinense DC., Scutellaria baicalensis Georgi, Pinellia ternata (Thunb.) Makino, Glycyrrhiza uralensis Fisch. ex DC., and nine other herbs, has been used to treat severe COVID-19 in clinical practice. The aim of this study was to compare the clinical efficacies of HJSS combination therapy and Western monotherapy against severe COVID-19 and to study the potential action mechanism of HJSS. From February 2020 to March 2020, 81 patients with severe COVID-19 in Wuhan Tongji Hospital were selected for retrospective cohort study. Network pharmacology was conducted to predict the possible mechanism of HJSS on COVID-19-related acute respiratory distress syndrome (ARDS). Targets of active components in HJSS were screened using the Traditional Chinese Medicine Systems Pharmacology (TCMSP) and PharmMapper databases. The targets of COVID-19 and ARDS were obtained from GeneCards and Online Mendelian Inheritance in Man databases. The key targets of HJSS in COVID-19 and ARDS were obtained based on the protein–protein interaction network (PPI). Kyoto Encyclopedia of Genes and Genomes analysis (KEGG) was conducted to predict the pathways related to the targets of HJSS in COVID-19 and ARDS. A “herb-ingredient-target-pathway” network was established using Cytoscape 3.2.7. Results showed that the duration of the negative conversion time of nucleic acid was shorter in patients who received HJSS combination therapy. HJSS combination therapy also relieved fever in patients with severe COVID-19. Network pharmacology analysis identified interleukin (IL) 6, tumor necrosis factor (TNF), vascular endothelial growth factor A (VEGFA), catalase (CAT), mitogen-activated protein kinase (MAPK) 1, tumor protein p53 (TP53), CC-chemokine ligand (CCL2), MAPK3, prostaglandin-endoperoxide synthase 2 (PTGS2), and IL1B as the key targets of HJSS in COVID-19-related ARDS. KEGG analysis suggested that HJSS improved COVID-19-related ARDS by regulating hypoxia-inducible factor (HIF)-1, NOD-like receptor, TNF, T cell receptor, sphingolipid, PI3K-Akt, toll-like receptor, VEGF, FoxO, and MAPK signaling pathways. In conclusion, HJSS can be used as an adjuvant therapy on severe COVID-19. The therapeutic mechanisms may be involved in inhibiting viral replication, inflammatory response, and oxidative stress and alleviating lung injury. Further studies are required to confirm its clinical efficacies and action mechanisms.

COVID-19 illness and autoimmune diseases: recent insights

BACKGROUND

The aim of this review is to explore whether patients with autoimmune diseases (AIDs) were at high risk of infection during the COVID-19 epidemic and how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic affected immune system.

METHODS

A systematic literature search was performed using the foreign databases (NCBI, web of science, EBSCO, ELSEVIER ScienceDirect) and Chinese databases (WanFang, CNKI (China National Knowledge Infrastructure), VIP, CBM) to locate all relevant publications (up to January 10, 2021). The search strategies used Medical Search Headings (MeSH) headings and keywords for "COVID-19" or "SARS-CoV-2" or "coronavirus" and "autoimmune disease".

RESULTS

This review evaluates the effect of SARS-CoV-2 on the immune system through ACE-2 receptor binding as the main pathway for cell attachment and invasion. It is speculated that SARS-COV-2 infection can activate lymphocytes and inflammatory response, which may play a role in the clinical onset of AIDs and also patients were treated with immunomodulatory drugs during COVID-19 outbreak. Preliminary studies suggested that the risk of developing severe forms of COVID-19 in patients with AIDs treated with immunomodulators or biologics might not increase. A large number of samples are needed for further verification, leading to an excessive immune response to external stimuli.

CONCLUSION

The relationship between autoimmune diseases and SARS-CoV-2 infection is complex. During the COVID-19 epidemic, individualized interventions for AIDs should be provided such as Internet-based service.

Clinical characteristics of hospitalized mild/moderate COVID-19 patients with a prolonged negative conversion time of SARS-CoV-2 nucleic acid detection

Background

The impact of COVID-19 has been devastating on a global scale. The negative conversion time (NCT) of SARS-CoV-2 RNA is closely related to clinical manifestation and disease progression in COVID-19 patients. Our study aimed to predict factors associated with prolonged NCT of SARS-CoV-2 RNA in mild/moderate COVID-19 patients.

Methods

The clinical features, laboratory data and treatment outcomes of COVID-19 patients were retrospectively analyzed. Then univariate and multivariate analysis were used to screen out risk factors of influencing prolonged NCT of SARS-CoV-2 RNA.

Results

Thirty-two hospitalized mild/moderate COVID-19 patients were enrolled. The general clinical symptoms were cough (78.1%), fever (75%), diarrhea (68.8%), expectoration (56.3%), and nausea (37.5%). More than 40% of the patients had decreased erythrocyte, hemoglobin and leucocyte and 93.8% patients were detected in abnormalities of chest CT. The median NCT of SARS-CoV-2 RNA was 19.5 days (IQR: 14.25–25). Univariate analysis found fever, nausea, diarrhea and abnormalities in chest CTs were positively associated with prolonged NCT of viral RNA (P< 0.05). The multivariate Cox proportional hazard model revealed that fever [Exp (B), 0.284; 95% CI, 0.114–0.707; P<0.05] and nausea [Exp (B), 0.257; 95%CI, 0.096–0.689; P<0.05] were two significant independent factors.

Conclusions

Fever and nausea were two significant independent factors in prolonged NCT of viral RNA in mild/moderate COVID-19 patients, which provided a useful references for disease progression and treatment of COVID-19.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-05851-z.

COVID-19: Integrating the Complexity of Systemic and Pulmonary Immunopathology to Identify Biomarkers for Different Outcomes

In the last few months, the coronavirus disease 2019 (COVID-19) pandemic has affected millions of people worldwide and has provoked an exceptional effort from the scientific community to understand the disease. Clinical evidence suggests that severe COVID-19 is associated with both dysregulation of damage tolerance caused by pulmonary immunopathology and high viral load. In this review article, we describe and discuss clinical studies that show advances in the understanding of mild and severe illness and we highlight major points that are critical for improving the comprehension of different clinical outcomes. The understanding of pulmonary immunopathology will contribute to the identification of biomarkers in an attempt to classify mild, moderate, severe and critical COVID-19 illness. The interface of pulmonary immunopathology and the identification of biomarkers are critical for the development of new therapeutic strategies aimed to reduce the systemic and pulmonary hyperinflammation in severe COVID-19.

Relationship between serum osteopontin levels and the severity of COVID-19 infection

Background

Coronavirus disease 2019 (COVID-19) is an acute inflammatory respiratory disease. Osteopontin (OPN) is a glycoprotein expressed in various cell types, such as bone, immune, smooth muscle, epithelial and endothelial cells. It also acts as a regulator of immune response. The aim of the present study was to reveal the place of serum osteopontin levels in predicting severity among patients with COVID-19.

Methods

This study included 84 patients, 43 female and 45 male. Patients were divided into 2 groups, group 1 non-severe group (n: 48), group 2 severe (n: 40). Demographic data, neutrophil, lymphocyte, platelet, white blood cell counts, albumin, procalcitonin, C‑reactive protein (CRP) and OPN levels were recorded. The OPN levels and these inflammatory parameters of the two groups were compared.

Results

There were no significant differences in terms of gender (female/male 25/23 vs. 18/22) and platelet count (178 K/μL vs. 191 K/μL) between the groups (p > 0.05). Ages (57.7 ± 17.0 years vs. 71.4 ± 12.8 years), procalcitonin (0.07 vs. 0.24 ng/mL), CRP (17 vs 158 mg/l), neutrophil count (3.7 vs 5.64 K/μL), WBC counts (5.38 vs 7.85 K/μL) and number of deaths (0 vs 26) (p < 0.001). The OPN levels (98.5 vs 13.75 ng/mL, p = 0.002) were found to be statistically higher, in group 2 than group 1.

Conclusion

The present study showed that OPN can be used to predict the severity in patients with COVID-19.

Neutrophils and COVID-19: The road so far

The SARS-Cov2 infection triggers a multisystem inflammatory disorder, knowing as COVID-19, a pandemic disease. This disease is characterized by acute respiratory distress syndrome, cytokine-driven hyperinflammation, and leukocytes count changes. The innate immune response has been linked to COVID-19 immunopathogenesis (e.g., dysfunctional IFN response and myeloid inflammation). In this regard, neutrophils have been highlighted as essential effector cells in the development of COVID-19. This review summarized the significant finds about neutrophils and its effector mechanisms (e.g., neutrophils enzymes and cytokines, neutrophil extracellular traps) in COVID-19 so far.

Low-Dose Radiation Therapy (LDRT) for COVID-19: Benefits or Risks?

The limited impact of treatments for COVID-19 has stimulated several phase 1 clinical trials of whole-lung low-dose radiation therapy (LDRT; 0.3-1.5 Gy) that are now progressing to phase 2 randomized trials worldwide. This novel but unconventional use of radiation to treat COVID-19 prompted the National Cancer Institute, National Council on Radiation Protection and Measurements and National Institute of Allergy and Infectious Diseases to convene a workshop involving a diverse group of experts in radiation oncology, radiobiology, virology, immunology, radiation protection and public health policy. The workshop was held to discuss the mechanistic underpinnings, rationale, and preclinical and emerging clinical studies, and to develop a general framework for use in clinical studies. Without refuting or endorsing LDRT as a treatment for COVID-19, the purpose of the workshop and this review is to provide guidance to clinicians and researchers who plan to conduct preclinical and clinical studies, given the limited available evidence on its safety and efficacy.

Neutrophil count to albumin ratio as a new predictor of mortality in patients with COVID-19 ınfection

SUMMARY BACKGROUND Coronavirus Disease 2019 is an acute inflammatory respiratory disease. It causes many changes in hemogram parameters. Low albumin levels are associated with mortality risk in hospitalized patients. The aim of the present study is to reveal the place of neutrophil count to albumin ratio in predicting mortality in patients with COVID-19. METHODS 144 patients, 65 females and 79 males, were included in the study. Patients were divided into 2 groups. Group 1 was the non-severe group (n:85), and Group 2 was severe (n:59). Demographic data, neutrophil, lymphocyte and platelet counts, albumin and C-reactive protein (CRP) levels were recorded. Neutrophil count to albumin ratio (NAR) was calculated by dividing the absolute neutrophil counts by the albumin levels. The NAR and levels of the two groups were then compared. RESULTS There were no significant differences in gender and platelet count (201 vs. 211 K/mL) between the groups (p>0,05). Ages (62.0 ± 14.3 vs 68.6 ± 12.2 years), albumin (33.1 vs 29.9 gr/L), CRP (33 vs 113 mg/l), neutrophil count (4 vs 7.24 K/mL), WBC counts (6.70 vs 8.50 K/mL), NAR values (113.5 vs 267.2) and number of Death (5 vs 33) were found to be statistically higher (p <0.001) in Group 2 than in Group 1. The NAR value of 201.5 showed mortality in all patients with COVID-19 to have 71.1% sensitivity and 71.7% specificity (AUC:0.736, 95% CI: 0.641-0.832, p<0.001) CONCLUSION The present study showed that NAR levels can be a cheap and simple marker for predicting mortality in patients with COVID-19.