Intravenous immunoglobulin (IVIg) therapy in hospitalised adult COVID-19 patients: A systematic review and meta-analysis

Tocilizumab and IVIG experience during the service follow-up in patients with severe COVID-19 pneumonia

Most SARS-CoV-2 infections are asymptomatic or cause only mild illness, but severe respiratory disease can develop, sometimes requiring oxygen support. Immunopathological damage resulting from an abnormal inflammatory response in patients with severe disease is known to be the main determinant of disease outcome. Studies show that anti-inflammatory therapies work best when used before widespread immunopathological damage has occurred. Similarly, it was thought that intravenous immunoglobulin (IVIG)-holding multiple immunomodulatory effects-would provide clinically favorable results, but recent studies suggest otherwise. Still, the literature shows few studies evaluating the efficacy of IVIG according to the time of administration and there are no studies comparing it with established treatments, such as tocilizumab. In this study, we aimed to evaluate the effects of early administration of tocilizumab and IVIG on clinical outcome in patients with severe COVID-19. Patients with progressive clinical and laboratory deterioration who received tocilizumab or IVIG between 07/2020 and 10/2020 in a public hospital ward were retrospectively evaluated. A total of 74 patients were identified, of whom 29 (39%) received IVIG only and 26 (35%) received tocilizumab only. As a result, patients with severe COVID-19 who received IVIG in early stages of the disease did not have better clinical outcomes regarding mortality, length of hospital stay and ICU admission compared to those who received tocilizumab. Moreover, there is no data to support the use of IVIG in COVID-19 patients with severe disease, as it is associated with more severe side effects and is more expensive than tocilizumab.

Immunobiology and immunotherapy of COVID-19

The SARS-CoV-2 outbreak in late 2019 triggered a major increase in activities related to immunobiology and immunotherapy to cope with and find solutions to end the COVID-19 pandemic. The unprecedented approach to research and development of drugs and vaccines against SARS-CoV-2 has substantially improved the understanding of immunobiology for COVID-19, which can also be applied to other infectious diseases. Major efforts were dedicated to the repurposing of existing antiviral drugs and the development of novel ones. For this reason, numerous approaches to evaluating interferons, immunoglobulins, and cytokine inhibitors have been conducted. Antibody-based therapies, especially employing monoclonal antibodies have also been on the agenda. Cell-based therapies involving dendritic cells, macrophages, and CAR T-cell approaches have been evaluated. Many existing antiviral drugs have been repurposed for COVID-19 and novel formulations have been tested. The extraordinarily rapid development of efficient vaccines led to the breakthrough of novel vaccine approaches such as mRNA-based vaccines saving millions of lives. Waning immunity of existing vaccines and emerging SARS-CoV-2 variants have required additional booster vaccinations and re-engineering of new versions of COVID-19 vaccines.

A review of intravenous immunoglobulin in the treatment of neuroimmune conditions, acute COVID-19 infection, and post-acute sequelae of COVID-19 Syndrome

Intravenous immunoglobulin (IVIG) is an immunomodulatory therapy that has been studied in several neuroimmune conditions, such as Guillain-Barré Syndrome, chronic inflammatory demyelinating polyneuropathy, multifocal motor neuropathy, and multiple sclerosis. It has also been proposed as a potential treatment option for acute COVID-19 infection and post-acute sequelae of SARS-CoV-2 infection (PASC). IVIG is thought to function by providing the recipient with a pool of antibodies, which can, in turn, modulate immune responses through multiple mechanisms including neutralization of cytokines and autoantibodies, saturation of neonatal fragment crystallizable receptors, inhibition of complement activation, and regulation of T and B cell mediated inflammation. In acute COVID-19, studies have shown that early administration of IVIG and plasmapheresis in severe cases can reduce the need for mechanical ventilation, shorten ICU and hospital stays, and lower mortality. Similarly, in PASC, while research is still in early stages, IVIG has been shown to alleviate persistent symptoms in small patient cohorts. Furthermore, IVIG has shown benefits in another condition which has symptomatic overlap with PASC, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), though studies have yielded mixed results. It is important to note that IVIG can be associated with several potential adverse effects, such as anaphylaxis, headaches, thrombosis, liver enzyme elevations and renal complications. In addition, the high cost of IVIG can be a deterrent for payers and patients. This review provides a comprehensive update on the use of IVIG in multiple neuroimmune conditions, ME/CFS, acute COVID-19, and PASC, as well as covers its history, production, pricing, and mechanisms of action. We also identify key areas of future research, including the need to optimize the use of Ig product dosing, timing, and patient selection across conditions, particularly in the context of COVID-19 and PASC.

Efficacy of COVID-19 Treatments in Intensive Care Unit: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objectives: Examining the cumulative evidence from randomized controlled trials (RCTs), evaluating the use of pharmacological agents for the treatment of COVID-19 infections in patients with critical illness. Data Sources: Databases Medline, Embase, Web of Science, Scopus, CINAHL, and Cochrane. Study Selection: Inclusion criteria were RCTs that enrolled patients with confirmed or suspected COVID-19 infection who are critically ill. Only RCTs that examined therapeutic agents against one another or no intervention, placebo, or standard of care, were included. Data Extraction: Pairs of reviewers extracted data independently. Outcomes of interest included the overall reported mortality defined as either the ICU mortality, hospital mortality, mortality within 28 days or mortality within 90 days. Data Synthesis: A total of 40 studies (11,613 patients) evaluated 50 therapeutic intervention arms divided into five main therapy categories; steroids, antiviral medications, immunomodulators, plasma therapies [intravenous immunoglobulins (IVIG), convalescent plasma and/or, therapeutic plasma exchange], and therapeutic anticoagulation. Immunomodulators was the only group with possible mortality benefit, risk ratio (RR) 0.83 (95% CI 0.73; 0.95), with nonsignificant heterogeneity (I 2 = 8%, p=0.36). In contrast, the other therapy groups showed no significant impact on mortality, as indicated by their respective pooled RRs: steroids [RR 0.91 (95% CI 0.82; 1.01), I 2 = 31%], antiviral medications [RR 1.11 (95% CI 0.82; 1.49), I 2 = 57%], plasma therapies [RR 0.77 (95% CI 0.58; 1.01), I 2 = 36%], and anticoagulation [RR 1.06 (95% CI 0.95; 1.18), I 2 = 0%]. Conclusions: This meta-analysis highlights both the heterogeneity and a lack of benefit from therapies evaluated during the COVID-19 pandemic. Many of the RCTs were developed based on limited observational data. Future RCTs investigating pharmaceutical interventions in critically ill patients during pandemics need to be designed based on better evidence.

Use of intravenous immunoglobulin for the treatment of severe COVID-19 in the Chris Hani Baragwanath Academic Hospital intensive care unit, Johannesburg, South Africa

Background

COVID-19 infection has a variable clinical presentation, with a small subgroup of patients developing severe disease, requiring intensive care with mechanical ventilation, with an increased mortality rate. South Africa (SA) has experienced multiple waves of this pandemic, spanning the pre-vaccine and vaccine periods. The method and initiation of treatment is a debated topic, changing according to evolving research and the literature. The present study investigated the use of high-dose intravenous immunoglobulin (IVIg) as a salvage therapy after initial medical treatment failure.

Objectives

To compare disease progression among critically ill COVID-19 pneumonia patients receiving IVIg therapy with that in patients receiving standard of care (SoC), in respect of inflammation, organ dysfunction and oxygenation.

Methods

This was a single-centre, retrospective study of patients admitted to the intensive care unit (ICU) at Chris Hani Baragwanath Academic Hospital, Johannesburg, SA, during the pre-vaccine COVID-19 pandemic. Demographics, inflammatory markers (C-reactive protein (CRP)), organ function (Sequential Organ Failure Assessment (SOFA) score), oxygenation (ratio of partial pressure of oxygen in arterial blood to fraction of inspiratory oxygen (P/F ratio)), overall mortality and complications (nosocomial infections and thromboembolism) were recorded and compared.

Results

We included 113 eligible patients in the study. The IVIg cohort had a significantly lower initial P/F ratio than the SoC cohort (p=0.01), but the change in P/F ratio was similar (p=0.54). Initial CRP and changes in CRP were similar in the two groups (p=0.38 and p=0.75, respectively), as were initial SOFA score and changes in SOFA score (p=0.18 and p=0.08, respectively) and vasopressor dose on day 0 and day 5 (p=0.97 and p=0.93, respectively). Duration of mechanical ventilation did not differ significantly between the IVIg group and the SoC group (p=0.13). There were no significant differences in measured complications between the two groups. On univariate analysis, the relative risk of death was 1.6 times higher (95% confidence interval (CI) 1.1 - 2.3) in the IVIg group; however, a logistical regression model demonstrated that only a higher P/F ratio (odds ratio (OR) 0.991; 95% CI 0.983 - 0.997) and higher mean airway pressure (OR 1.283; 95% CI 1.026 - 1.604) were significantly associated with ICU mortality.

Conclusion

Use of IVIg in our study was directed at an older population, with significantly worse oxygenation. We found no evidence of adverse effects of immunoglobulin therapy; however, we found no benefit either. Only the P/F ratio and mean airway pressure independently predicted ICU mortality.

Contribution of the study

During the COVID-19 pandemic, treatment protocols changed in response to the evolving literature. Hospitals were faced with choosing a treatment modality that they believed at the time had benefit. Chris Hani Baragwanath Hospital in Johannesburg, South Africa (SA), incorporated IVIg into its treatment protocols for patients with severe COVID pneumonia requiring ICU admission. This study retrospectively analysed the use of IVIg therapy in the hope of creating a more robust understanding of its safety and efficacy as a treatment option for SA patients in the future.

Falsely abnormal serum protein electrophoresis after administration of intravenous immunoglobulins (IVIG): A retrospective cohort study

Intravenous immunoglobulin (IVIG) therapy, used in several neurologic, hematologic, immunologic and dermatologic conditions, is known to interfere with the results of some serum laboratory tests. We analyzed the potential interference of IVIG on serum protein electrophoresis (SPEP) by reviewing more than a decade of SPEP studies performed by the clinical immunology laboratory of the Johns Hopkins Hospital. Of the total 100,350 SPEP performed between January 1, 2013 and December 31, 2023, 395 contained the keyword IVIG in the pathologist report, contributed by 348 patients confirmed to have received IVIG by chart review. Of the 348 patients, 20 (6 %) had a M-spike on SPEP suggestive of monoclonal gammopathy, while 328 (94 %) did not have it. Of the 20 patients, 14 received IVIG within 30 days from the SPEP collection date, while 6 received beyond 30 days. Serum immunofixation electrophoresis (SIFE) and clinical follow up showed no evidence of monoclonal gammopathy in 5 of the 14 patients. Overall, this 11-year retrospective cohort study showed that 5 of 348 (1.4 %) patients treated with IVIG and tested by SPEP had a false M-spike, that is a spike not confirmed to be caused by a monoclonal gammopathy by subsequent studies. Although small, the false positive rate of 1.4 % suggests that integrating knowledge of recent IVIG administration into the pathologist report would reduce SPEP misdiagnosis.

Efficacy and safety of trimodulin in patients with severe COVID-19: results from a randomised, placebo-controlled, double-blind, multicentre, phase II trial (ESsCOVID)

BACKGROUND

Trimodulin (human polyvalent immunoglobulin [Ig] M ~ 23%, IgA ~ 21%, IgG ~ 56% preparation) has previously been associated with a lower mortality rate in a subpopulation of patients with severe community-acquired pneumonia on invasive mechanical ventilation (IMV) and with clear signs of inflammation. The hypothesis for the ESsCOVID trial was that trimodulin may prevent inflammation-driven progression of severe coronavirus disease 2019 (COVID-19) to critical disease or even death.

METHODS

Adults with severe COVID-19 were randomised to receive intravenous infusions of trimodulin or placebo for 5 consecutive days in addition to standard of care. The primary efficacy endpoint was a composite of clinical deterioration (Days 6-29) and 28-day all-cause mortality (Days 1-29).

RESULTS

One-hundred-and-sixty-six patients received trimodulin (n = 84) or placebo (n = 82). Thirty-three patients died, nine during the treatment phase. Overall, 84.9% and 76.5% of patients completed treatment and follow-up, respectively. The primary efficacy endpoint was reported in 33.3% of patients on trimodulin and 34.1% of patients on placebo (P = 0.912). No differences were observed in the proportion of patients recovered on Day 29, days of invasive mechanical ventilation, or intensive care unit-free days. Rates of treatment-emergent adverse events were comparable. A post hoc analysis was conducted in patients with early systemic inflammation by excluding those with high CRP (> 150 mg/L) and/or D-dimer (≥ 3 mg/L) and/or low platelet counts (< 130 × 109/L) at baseline. Forty-seven patients in the trimodulin group and 49 in the placebo group met these criteria. A difference of 15.5 percentage points in clinical deterioration and mortality was observed in favour of trimodulin (95% confidence interval: -4.46, 34.78; P = 0.096).

CONCLUSION

Although there was no difference in the primary outcome in the overall population, observations in a subgroup of patients with early systemic inflammation suggest that trimodulin may have potential in this setting that warrants further investigation. ESSCOVID WAS REGISTERED PROSPECTIVELY AT CLINICALTRIALS.GOV ON OCTOBER 6, 2020.: NCT04576728.

Intravenous immunoglobulin for treatment of hospitalized COVID-19 patients: an evidence mapping and meta-analysis

BACKGROUND

The clinical efficacy and safety of intravenous immunoglobulin (IVIg) treatment for COVID-19 remain controversial. This study aimed to map the current status and gaps of available evidence, and conduct a meta-analysis to further investigate the benefit of IVIg in COVID-19 patients.

METHODS

Electronic databases were searched for systematic reviews/meta-analyses (SR/MAs), primary studies with control groups, reporting on the use of IVIg in patients with COVID-19. A random-effects meta-analysis with subgroup analyses regarding study design and patient disease severity was performed. Our outcomes of interest determined by the evidence mapping, were mortality, length of hospitalization (days), length of intensive care unit (ICU) stay (days), number of patients requiring mechanical ventilation, and adverse events.

RESULTS

We included 34 studies (12 SR/MAs, 8 prospective and 14 retrospective studies). A total of 5571 hospitalized patients were involved in 22 primary studies. Random-effects meta-analyses of very low to moderate evidence showed that there was little or no difference between IVIg and standard care or placebo in reducing mortality (relative risk [RR] 0.91; 95% CI 0.78-1.06; risk difference [RD] 3.3% fewer), length of hospital (mean difference [MD] 0.37; 95% CI - 2.56, 3.31) and ICU (MD 0.36; 95% CI - 0.81, 1.53) stays, mechanical ventilation use (RR 0.92; 95% CI 0.68-1.24; RD 2.8% fewer), and adverse events (RR 0.98; 95% CI 0.84-1.14; RD 0.5% fewer) of patients with COVID-19. Sensitivity analysis using a fixed-effects model indicated that IVIg may reduce mortality (RR 0.76; 95% CI 0.60-0.97), and increase length of hospital stay (MD 0.68; 95% CI 0.09-1.28).

CONCLUSION

Very low to moderate certainty of evidence indicated IVIg may not improve the clinical outcomes of hospitalized patients with COVID-19. Given the discrepancy between the random- and fixed-effects model results, further large-scale and well-designed RCTs are warranted.

New insight into the intravenous immunoglobulin treatment in Multisystem Inflammatory Syndrome in children and adults

Within 6 months of the coronavirus pandemic, a new disease entity associated with a multisystem hyperinflammation syndrome as a result of a previous infection with the SARS-CoV-2 virus is increasingly being identified in children termed Multisystem Inflammatory Syndrome in Children (MIS-C) and more recently in adults(MIS-A). Due to its clinical similarity with Kawasaki Disease, some institutions have used intravenous immunoglobulins and steroids as first line agents in the management of the disease. We seek to find how effective intravenous immunoglobulin therapy is across these two disease entities. A comprehensive English literature search was conducted across PubMed, MEDLINE, and EMBASE databases using the keywords multisystem inflammatory syndrome in children/adults and treatment. All major online libraries concerning the diagnosis and treatment of MIS-C and MIS-A were searched. Relevant papers were read, reviewed, and analyzed. The use of intravenous immunoglobulins (IVIG) and steroids for the treatment of multisystemic inflammatory syndrome in children(MIS-C) is well established and recommended by multiple pediatric governing institutions. However, there is still no optimal treatment guideline or consensus on the use of IVIG in adults. The use of IVIG in both the child and adult populations may lower the risk of treatment failure and the need for adjunctive immunomodulatory therapy. Despite the promising results of IVIG use for the management of MIS-C and MIS-A, considering the pathophysiological differences between MIS-C and MIS-A, healthcare professionals need to further assess the differences in disease risk and treatment. The optimal dose, frequency, and duration of treatment are still unknown, more research is needed to establish treatment guidelines.

Multifaceted Tissue-Protective Functions of Polyvalent Immunoglobulin Preparations in Severe Infections-Interactions with Neutrophils, Complement, and Coagulation Pathways

Severe infections induce immune defense mechanisms and initial tissue damage, which produce an inflammatory neutrophil response. Upon dysregulation of these responses, inflammation, further tissue damage, and systemic spread of the pathogen may occur. Subsequent vascular inflammation and activation of coagulation processes may cause microvascular obstruction at sites distal to the primary site of infection. Low immunoglobulin (Ig) M and IgG levels have been detected in patients with severe infections like sCAP and sepsis, associated with increased severity and mortality. Based on Ig's modes of action, supplementation with polyvalent intravenous Ig preparations (standard IVIg or IgM/IgA-enriched Ig preparations) has long been discussed as a treatment option for severe infections. A prerequisite seems to be the timely administration of Ig preparations before excessive tissue damage has occurred and coagulopathy has developed. This review focuses on nonclinical and clinical studies that evaluated tissue-protective activities resulting from interactions of Igs with neutrophils, complement, and the coagulation system. The data indicate that coagulopathy, organ failure, and even death of patients can possibly be prevented by the timely combined interactions of (natural) IgM, IgA, and IgG with neutrophils and complement.

The prevention and treatment of COVID-19 in patients treated with hemodialysis

Patients treated with hemodialysis are often immunocompromised due to concomitant disease. As a result, this population is at high risk of infection and mortality from COVID-19. In addition to symptomatic treatment, a series of antiviral drugs targeting COVID-19 are now emerging. However, these antivirals are used mainly in mild or moderate patients with high-risk factors for progression to severe disease and are not available as pre- or post-exposure prophylaxis for COVID-19. There is a lack of clinical data on the use of anti-COVID-19 drugs, especially in patients treated with hemodialysis, therefore, vaccination remains the main measure to prevent SARS-CoV-2 infection in these patients. Here, we review the clinical features and prognosis of patients on hemodialysis infected with SARS-CoV-2, the main anti-COVID-19 drugs currently available for clinical use, and the safety and efficacy of anti-COVID-19 drugs or COVID-19 vaccination in patients treated with hemodialysis. This information will provide a reference for the treatment and vaccination of COVID-19 in patients treated with hemodialysis and maximize the health benefits of these patients during the outbreak.

SARS-CoV-2 neutralising antibody therapies: Recent advances and future challenges

The COVID-19 pandemic represents an unparalleled global public health crisis. Despite concerted research endeavours, the repertoire of effective treatment options remains limited. However, neutralising-antibody-based therapies hold promise across an array of practices, encompassing the prophylaxis and management of acute infectious diseases. Presently, numerous investigations into COVID-19-neutralising antibodies are underway around the world, with some studies reaching clinical application stages. The advent of COVID-19-neutralising antibodies signifies the dawn of an innovative and promising strategy for treatment against SARS-CoV-2 variants. Comprehensively, our objective is to amalgamate contemporary understanding concerning antibodies targeting various regions, including receptor-binding domain (RBD), non-RBD, host cell targets, and cross-neutralising antibodies. Furthermore, we critically examine the prevailing scientific literature supporting neutralising antibody-based interventions, and also delve into the functional evaluation of antibodies, with a particular focus on in vitro (vivo) assays. Lastly, we identify and consider several pertinent challenges inherent to the realm of COVID-19-neutralising antibody-based treatments, offering insights into potential future directions for research and development.

COVID-19: a modern trigger for Guillain-Barre syndrome, myasthenia gravis, and small fiber neuropathy

COVID-19 infection has had a profound impact on society. During the initial phase of the pandemic, there were several suggestions that COVID-19 may lead to acute and protracted neurologic sequelae. For example, peripheral neuropathies exhibited distinctive features as compared to those observed in critical care illness. The peripheral nervous system, lacking the protection afforded by the blood-brain barrier, has been a particular site of sequelae and complications subsequent to COVID-19 infection, including Guillain-Barre syndrome, myasthenia gravis, and small fiber neuropathy. We will discuss these disorders in terms of their clinical manifestations, diagnosis, and treatment as well as the pathophysiology in relation to COVID-19.

Restraint Stress-Induced Immunosuppression Is Associated with Concurrent Macrophage Pyroptosis Cell Death in Mice

Psychological stress is widely acknowledged as a major contributor to immunosuppression, rendering individuals more susceptible to various diseases. The complex interplay between the nervous, endocrine, and immune systems underlies stress-induced immunosuppression. However, the underlying mechanisms of psychological-stress-induced immunosuppression remain unclear. In this study, we utilized a restraint stress mouse model known for its suitability in investigating physiological regulations during psychological stress. Comparing it with cold exposure, we observed markedly elevated levels of stress hormones corticosterone and cortisol in the plasma of mice subjected to restraint stress. Furthermore, restraint-stress-induced immunosuppression differed from the intravenous immunoglobulin-like immunosuppression observed in cold exposure, with restraint stress leading to increased macrophage cell death in the spleen. Suppression of pyroptosis through treatments of inflammasome inhibitors markedly ameliorated restraint-stress-induced spleen infiltration and pyroptosis cell death of macrophages in mice. These findings suggest that the macrophage pyroptosis associated with restraint stress may contribute to its immunosuppressive effects. These insights have implications for the development of treatments targeting stress-induced immunosuppression, emphasizing the need for further investigation into the underlying mechanisms.

Intravenous immunoglobulin as a potential treatment for long COVID

INTRODUCTION

On 31 July 2023, the United States Department of Health and Human Services announced the formation of the Office of Long COVID Research and Practice and the United States National Institutes of Health (NIH) opened enrollment for the therapeutic arm of the RECOVER initiative, a prospective, randomized study to evaluate new treatment options for long coronavirus disease 2019 (long COVID).

AREAS COVERED

One of the first drugs to be studied in this nationwide initiative is intravenous immunoglobulin (IVIG), which will be a treatment option for subjects enrolled in RECOVER-AUTO, a randomized trial to investigate therapeutic strategies for autonomic dysfunction related to long COVID.

EXPERT OPINION

IVIG is a mixture of human antibodies (human immunoglobulin) that has been widely used to treat a variety of diseases, including immune thrombocytopenia purpura, Kawasaki disease, chronic inflammatory demyelinating polyneuropathy, and certain infections such as influenza, human immunodeficiency virus, and measles. However, the role of IVIG in the treatment of post-COVID-19 conditions is uncertain. This manuscript examines what is known about IVIG in the treatment of long COVID and explores how this therapeutic agent may be used in the future to address this condition.

Mendelian randomization analysis identified tumor necrosis factor as being associated with severe COVID-19

Background: Observational studies have shown that anti-tumor necrosis factor (TNF) therapy may be beneficial for patients with coronavirus disease 2019 (COVID-19). Nevertheless, because of the methodological restrictions of traditional observational studies, it is a challenge to make causal inferences. This study involved a two-sample Mendelian randomization analysis to investigate the causal link between nine TNFs and COVID-19 severity using publicly released genome-wide association study summary statistics. Methods: Summary statistics for nine TNFs (21,758 cases) were obtained from a large-scale genome-wide association study. Correlation data between single-nucleotide polymorphisms and severe COVID-19 (18,152 cases vs. 1,145,546 controls) were collected from the COVID-19 host genetics initiative. The causal estimate was calculated by inverse variance-weighted (IVW), MR-Egger, and weighted median methods. Sensitivity tests were conducted to assess the validity of the causal relationship. Results: Genetically predicted TNF receptor superfamily member 6 (FAS) positively correlated with the severity of COVID-19 (IVW, odds ratio = 1.10, 95% confidence interval = 1.01-1.19, p = 0.026), whereas TNF receptor superfamily member 5 (CD40) was protective against severe COVID-19 (IVW, odds ratio = 0.92, 95% confidence interval = 0.87-0.97, p = 0.002). Conclusion: Genetic evidence from this study supports that the increased expression of FAS is associated with the risk of severe COVID-19 and that CD40 may have a potential protective effect against COVID-19.

Innate and adaptive immunity to SARS-CoV-2 and predisposing factors

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2), has affected all countries worldwide. Although some symptoms are relatively mild, others are still associated with severe and even fatal clinical outcomes. Innate and adaptive immunity are important for the control of SARS-CoV-2 infections, whereas a comprehensive characterization of the innate and adaptive immune response to COVID-19 is still lacking and the mechanisms underlying immune pathogenesis and host predisposing factors are still a matter of scientific debate. Here, the specific functions and kinetics of innate and adaptive immunity involved in SARS-CoV-2 recognition and resultant pathogenesis are discussed, as well as their immune memory for vaccinations, viral-mediated immune evasion, and the current and future immunotherapeutic agents. We also highlight host factors that contribute to infection, which may deepen the understanding of viral pathogenesis and help identify targeted therapies that attenuate severe disease and infection.

2023 Chinese expert consensus on the impact of COVID-19 on the management of cardiovascular diseases

The primary site of infection in COVID-19 exhibit is the respiratory system, but multiple organ systems could be affected. The virus could directly invade cardiomyocytes. Alternatively, cytokine storm could lead to myocardial injury. More importantly, the management of existing cardiovascular diseases must be re-examined in COVID-19 due to, for example, interaction between antiviral agents and with a wide variety of pharmacological agents. The Branch of Cardiovascular Physicians of Chinese Medical Doctor Association organized a panel of experts in cardiovascular and related fields to discuss this important issue, and formulated the "2023 Chinese Expert Consensus on the Impact of COVID-19 on the Management of Cardiovascular Diseases." The Consensus was drafted on the basis of systematic review of existing evidence and diagnosis and treatment experience, and covers three major aspects: myocardial injury caused by COVID-10 and COVID-19 vaccine, the impact of COVID-19 on patients with cardiovascular disease, and the impact of COVID-19 on the cardiovascular system of healthy people, and rehabilitation guidance recommendations. The Consensus involves 11 core clinical issues, including incidence, pathogenesis, clinical manifestations, treatment strategies, prognosis, and rehabilitation. It is our hope that this Consensus will provide a practical guidance to cardiologists in the management of cardiovascular diseases in the new era of COVID-19 pandemic.

Benefits of high-dose intravenous immunoglobulin on mortality in patients with severe COVID-19: An updated systematic review and meta-analysis

Background

The clinical benefits of high-dose intravenous immunoglobulin (IVIg) in treating COVID-19 remained controversial.

Methods

We systematically searched databases up to February 17, 2022, for studies examining the efficacy of IVIg compared to routine care. Meta-analyses were conducted using the random-effects model. Subgroup analysis, meta-regression, and trial series analysis w ere performed to explore heterogeneity and statistical significance.

Results

A total of 4,711 hospitalized COVID-19 patients (1,925 IVIg treated and 2786 control) were collected from 17 studies, including five randomized controlled trials (RCTs) and 12 cohort studies. The application of IVIg was not associated with all-cause mortality (RR= 0.89 [0.63, 1.26], P= 0.53; I² = 75%), the length of hospital stays (MD= 0.29 [-3.40, 6.44] days, P= 0.88; I2 = 96%), the needs for mechanical ventilation (RR= 0.93 ([0.73, 1.19], P= 0.31; I2 = 56%), or the incidence of adverse events (RR= 1.15 [0.99, 1.33], P= 0.06; I2 = 20%). Subgroup analyses showed that overall mortality among patients with severe COVID-19 was reduced in the high-dose IVIg subgroup (RR= 0.33 [0.13, 0.86], P= 0.02, I² = 68%; very low certainty).

Conclusions

Results of this study suggest that severe hospitalized COVID-19 patients treated with high-dose IVIg would have a lower risk of death than patients with routine care.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021231040, identifier CRD42021231040.