Point-of-care ultrasound in nephrology:A private practice viewpoint

Point-of-care ultrasound(POCUS)is a limited ultrasound examination performed by the clinician at the bedside,emerging as a complement to physical examination across various medical specialties.In the field of nephrology,its integration has been gradual,primarily limited to guiding procedures like temporary dialysis catheter placement or,in some cases,diagnostic kidney ultrasounds.In reality,the assessment of hemodynamic status at the bedside holds immense value for nephrologists,yet there exists limited awareness among practitioners regarding its implementation.While there is a growing trend towards incorporating multiorgan POCUS training in fellowship programs,private practice nephrologists remain relatively uninformed.This discussion explores the untapped potential of POCUS as a valuable diagnostic tool in everyday nephrology practice,demonstrating its effectiveness in diverse clinical settings,ranging from medical wards to outpatient dialysis units.Additionally,we delve into the challenges hindering its widespread adoption and consider the future trajectory of this innovative approach.

Seeing beneath the surface:Harnessing point-of-care ultrasound for internal jugular vein evaluation

Point-of-care ultrasound(POCUS)of the internal jugular vein(IJV)offers a noninvasive means of estimating right atrial pressure(RAP),especially in cases where the inferior vena cava is inaccessible or unreliable due to conditions such as liver disease or abdominal surgery.While many clinicians are familiar with visually assessing jugular venous pressure through the internal jugular vein,this method lacks sensitivity.The utilization of POCUS significantly enhances the visualization of the vein,leading to a more accurate identification.It has been demonstrated that combining IJV POCUS with physical examination enhances the specificity of RAP estimation.This review aims to provide a comprehensive summary of the various sonographic techniques available for estimating RAP from the internal jugular vein,drawing upon existing data.

Seeing through the myths:Practical aspects of diagnostic point-ofcare ultrasound in nephrology

Point of care ultrasonography(POCUS)is emerging as an invaluable tool for guiding patient care at the bedside,providing real-time diagnostic information to clinicians.Today,POCUS is recognized as the fifth pillar of bedside clinical examination,alongside inspection,palpation,percussion,and auscultation.In spite of growing interest,the adoption of diagnostic POCUS in nephrology remains limited,and comprehensive training beyond kidney ultrasound is offered in only a few fellowship programs.Moreover,several misconceptions and barriers surround the integration of POCUS into day-to-day nephrology practice.These include myths about its scope,utility,impact on patient outcomes and legal implications.In this minireview,we address some of these issues to encourage wider and proper utilization of POCUS.

Point of care ultrasonography in onco-nephrology:A stride toward better physical examination

Onco-Nephrology is an emerging subspecialty of Nephrology that focuses on a broad spectrum of renal disorders that can arise in patients with cancer.It encompasses acute kidney injury(AKI),complex fluid,electrolyte,and acid-base disorders,as well as chronic kidney disease caused or exacerbated by cancer and/or its treatment.In many such scenarios including AKI and hyponatremia,objective evaluation of hemodynamics is vital for appropriate management.Point of care ultrasonography(POCUS)is a limited ultrasound exam performed at the bedside and interpreted by the treating physician intended to answer focused clinical questions and guide therapy.Compared to conventional physical examination,POCUS offers substantially higher diagnostic accuracy for various structural and hemodynamic derangements.In this narrative review,we provide an overview of the utility of POCUS enhanced physical examination for the Onconephrologist supported by the current evidence and our experience-based opinion.

J-shaped association between dietary thiamine intake and the risk of cognitive decline in cognitively healthy,older Chinese individuals

Background The prospective association of dietary thiamine intake with the risk of cognitive decline among the general older adults remains uncertain.Aims To investigate the association between dietary thiamine intake and cognitive decline in cognitively healthy,older Chinese individuals.Methods The study included a total of 3106 participants capable of completing repeated cognitive function tests.Dietary nutrient intake information was collected through 3-day dietary recalls and using a 3-day food-weighed method to assess cooking oil and condiment consumption.Cognitive decline was defined as the 5-year decline rate in global or composite cognitive scores based on a subset of items from the Telephone Interview for Cognitive Status-modified.Results The median follow-up duration was 5.9 years.There was a J-shaped relationship between dietary thiamine intake and the 5-year decline rate in global and composite cognitive scores,with an inflection point of 0.68 mg/day(95%confidence interval(Cl):0.56 to 0.80)and a minimal risk at 0.60-1.00 mg/day of dietary thiamine intake.Before the inflection point,thiamine intake was not significantly associated with cognitive decline.Beyond the inflection point,each unit increase in thiamine intake(mg/day)was associated with a significant decrease of 4.24(95%Cl:2.22 to 6.27)points in the global score and 0.49(95%Cl:0.23 to 0.76)standard units in the composite score within 5 years.A stronger positive association between thiamine intake and cognitive decline was observed in those with hypertension,obesity and those who were non-smokers(all p<0.05).Conclusions This study revealed a J-shaped association between dietary thiamine intake and cognitive decline in cognitively healthy,older Chinese individuals,with an inflection point at 0.68 mg/day and a minimal risk at 0.60-1.00 mg/day of dietary thiamine intake.

Long-term outcomes of titanium-nitride-oxide coated stents and drug-eluting stents in acute coronary syndrome:A systematic review and meta-analysis

BACKGROUND In severe cases of coronary artery disease,percutaneous coronary intervention provide promising results.The stent used could be a drug-eluting stent(DES)or a titanium-nitride-oxide coated stent(TiNOS).AIM To compare the 5-year effectiveness and safety of the two stent types.METHODS The following systematic review and meta-analysis was conducted in accordance with the preferred reporting items for systematic reviews and meta-analysis guidelines,and PubMed/MEDLINE,Scopus,and Cochrane Central were searched from inception till August 2023.Primary outcomes were major adverse cardiac events(MACE),cardiac death,myocardial infarction(MI),cardiac death or MI,and ischemia-driven total lesion revascularization(ID-TLR).RESULTS Four randomized controlled trials(RCT),which analyzed a sum total of 3045 patients with acute coronary syndrome(ACS)after a median follow-up time of 5 years were included.Though statistically insignificant,an increase in the ID-TLR was observed in patients receiving TiNOSs vs DESs.In addition,MI,cardiac death and MI,and definite stent thrombosis(DST)were significantly decreased in the TiNOS arm.Baseline analysis revealed no significant results with meta-regression presenting non-ST elevated MI(NSTEMI)as a statistically significant covariate in the outcome of MACE.CONCLUSION TiNOS was found to be superior to DES in terms of MI,cardiac death or MI,and DST outcomes,however,the effect of the two stent types on ID-TLR and MACE was not significant.A greater number of studies are required to establish an accurate comparison of patient outcomes in TiNOS and DES.

Point-of-care ultrasonography in cirrhosis-related acute kidney injury:How I do it

Discerning the etiology of acute kidney injury(AKI)in cirrhotic patients remains a formidable challenge due to diverse and overlapping causes.The conventional approach of empiric albumin administration for suspected volume depletion may inadvertently lead to fluid overload.In the recent past,point-of-care ultrasonography(POCUS)has emerged as a valuable adjunct to clinical assessment,offering advantages in terms of diagnostic accuracy,rapidity,cost-effectiveness,and patient satisfaction.This review provides insights into the strategic use of POCUS in evaluating cirrhotic patients with AKI.The review distinguishes basic and advanced POCUS,emphasizing a 5-point basic POCUS protocol for efficient assessment.This protocol includes evaluations of the kidneys and urinary bladder for obstructive nephropathy,lung ultrasound for detecting extravascular lung water,inferior vena cava(IVC)ultrasound for estimating right atrial pressure,internal jugular vein ultrasound as an alternative to IVC assessment,and focused cardiac ultrasound for assessing left ventricular(LV)systolic function and identifying potential causes of a plethoric IVC.Advanced POCUS delves into additional Doppler parameters,including stroke volume and cardiac output,LV filling pressures and venous congestion assessment to diagnose or prevent iatrogenic fluid overload.POCUS,when employed judiciously,enhances the diagnostic precision in evaluating AKI in cirrhotic patients,guiding appropriate therapeutic interventions,and minimizing the risk of fluid-related complications.

Cardiac evaluation of renal transplant candidates with heart failure

Patients with advanced kidney disease are at elevated risk of developing heart failure and appropriate risk stratification is important to permit them to receive kidney transplantation.The American Heart Association and American College of Cardiology joint statement provides guidance on risk stratification for the major cause of heart failure for these patients in its recommendations for coronary heart disease.Herein we provide an overview of the available literature on risk strati-fication for nonischemic heart failure and functional heart disease states such as pulmonary hypertension.Many of these options for optimizing these patients be-fore transplant include optimizing their volume status,often with more agg-ressive ultrafiltration.Kidney transplantation remains the treatment of choice for patients with advanced kidney disease and cardiac disease,the correction of the azotemic substances with kidney transplantation has been associated with imp-roved survival than remaining on dialysis long-term.The findings in the studies reviewed here are expected to help clinicians refine current strategies for evalua-ting potential kidney transplant recipients.

Development of donor specific antibodies after SARS-CoV-2 vaccination:What do we know so far?

Vaccination against Coronavirus disease-19(COVID-19)was pivotal to limit spread,morbidity and mortality.Our aim is to find out whether vaccines against COVID-19 lead to an immunological response stimulating the production of de novo donor specific antibodies(DSAs)or increase in mean fluorescence intensity(MFI)of pre-existing DSAs in kidney transplant recipients(KTRs).This study involved a detailed literature search through December 2nd,2023 using PubMed as the primary database.The search strategy incorporated a combination of relevant Medical Subject Headings terms and keywords:"COVID-19","SARS-CoV-2 Vaccination","Kidney,Renal Transplant",and"Donor specific antibodies".The results from related studies were collated and analyzed.A total of 6 studies were identified,encompassing 460 KTRs vaccinated against COVID-19.Immunological responses were detected in 8 KTRs of which 5 had increased MFIs,1 had de novo DSA,and 2 were categorized as either having de novo DSA or increased MFI.There were 48 KTRs with pre-existing DSAs prior to vaccination,but one study(Massa et al)did not report whether pre-existing DSAs were associated with post vaccination outcomes.Of the remaining 5 studies,35 KTRs with pre-existing DSAs were identified of which 7 KTRs(20%)developed de novo DSAs or increased MFIs.Overall,no immunological response was detected in 452(98.3%)KTRs.Our study affirms prior reports that COVID-19 vaccination is safe for KTRs,especially if there are no pre-existing DSAs.However,if KTRs have pre-existing DSAs,then an increased immunological risk may be present.These findings need to be taken cautiously as they are based on a limited number of patients so further studies are still needed for confirmation.

Point-of-care ultrasonography spotlight:Could venous excess ultrasound serve as a shared language for internists and intensivists?

Point-of-care ultrasonography(POCUS),particularly venous excess ultrasound(VExUS)is emerging as a valuable bedside tool to gain real-time hemodynamic insights.This modality,derived from hepatic vein,portal vein,and intrarenal vessel Doppler patterns,offers a scoring system for dynamic venous congestion assessment.Such an assessment can be crucial in effective management of patients with heart failure exacerbation.It facilitates diagnosis,quantification of congestion,prognostication,and monitoring the efficacy of decongestive therapy.As such,it can effectively help to manage cardiorenal syndromes in various clinical settings.Extended or eVExUS explores additional veins,potentially broadening its applications.While VExUS demonstrates promising outcomes,challenges persist,particularly in cases involving renal and liver parenchymal disease,arrhythmias,and situations of pressure and volume overload overlap.Proficiency in utilizing spectral Doppler is pivotal for clinicians to effectively employ this tool.Hence,the integration of POCUS,especially advanced applications like VExUS,into routine clinical practice necessitates enhanced training across medical specialties.

Long-term follow-up of kidney transplant recipients admitted to a tertiary care transplant center with SARS-CoV-2

BACKGROUND Kidney transplant recipients(KTR)are at risk of severe coronavirus disease 2019(COVID-19)disease and mortality after severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection.We predicted that hospitalization for COVID-19 and subsequent admission to the intensive care unit(ICU)would yield worse outcomes in KTRs.cohort was stratified by ICU admission.Outcomes of interest included risk factors for ICU admission and mortality,length of stay(LOS),respiratory symptoms at admission,all-cause graft failure at the last follow-up,and death related to COVID-19.RESULTS 96 KTRs were hospitalized for SARS-COV-2 infection.21(22%)required ICU admission.The ICU group had longer hospital LOS(21.8 vs 8.6 days,P<0.001)and were more likely to experience graft failure(81%vs 31%,P<0.001).Of those admitted to the ICU,76%had death at last-follow up,and 71%had death related to COVID-19.Risk factors for ICU admission included male sex(aHR:3.11,95%CI:1.04-9.34;P=0.04).Risk factors for all-cause mortality and COVID-19-related mortality included ICU admission and advanced age at SARS-CoV-2 diagnosis.Mortality was highest within a month of COVID-19 diagnosis,with the ICU group having increased risk of all-cause(aHR:11.2,95%CI:5.11-24.5;P<0.001)and COVID-19-related mortality(aHR:27.2,95%CI:8.69-84.9;P<0.001).CONCLUSION ICU admission conferred an increased risk of mortality,graft failure,and longer LOS.One-fifth of those hospit-alized died of COVID-19,reflecting the impact of COVID-19-related morbidity and mortality among KTRs.

Point-of-care ultrasound in diagnosis and management of congestive nephropathy

Congestive nephropathy is kidney dysfunction caused by the impact of elevated venous pressures on renal hemodynamics.As a part of cardiorenal syndrome,the diagnosis is usually made based on history and physical examination,with findings such as jugular venous distension,a third heart sound,and vital signs as supporting findings.More recently,however,these once though objective measures have come under scrutiny for their accuracy.At the same time,bedside ultrasound has increased in popularity and is routinely being used by clinicians to take some of the guess work out of making the diagnosis of volume overload and venous congestion.In this mini-review,we will discuss some of the traditional methods used to measure venous congestion,describe the role of point-of-care ultrasound and how it can ameliorate a clinician’s evaluation,and offer a description of venous excess ultrasound score,a relatively novel scoring technique used to objectively quantify congestion.While there is a paucity of published large scale clinical trials evaluating the potential benefit of ultrasonography in venous congestion compared to gold standard invasive measurements,more study is underway to solidify the role of this objective measure in daily clinical practice.

Association of mineral and bone biomarkers with adverse cardiovascular outcomes and mortality in the German Chronic Kidney Disease(GCKD)cohort

Mineral and bone disorder(MBD)in chronic kidney disease(CKD)is tightly linked to cardiovascular disease(CVD).In this study,we aimed to compare the prognostic value of nine MBD biomarkers to determine those associated best with adverse cardiovascular(CV)outcomes and mortality.In 5217 participants of the German CKD(GCKD)study enrolled with an estimated glomerular filtration rate(eG FR)between 30–60 mL·min-1 per 1.73 m2 or overt proteinuria,serum osteoprotegerin(OPG),C-terminal fibroblast growth factor-23(FGF23),intact parathyroid hormone(iP TH),bone alkaline phosphatase(BAP),cross-linked C-telopeptide of type 1 collagen(CTX1),procollagen 1intact N-terminal propeptide(P1NP),phosphate,calcium,and 25-OH vitamin D were measured at baseline.Participants with missing values among these parameters(n=971)were excluded,leaving a total of 4246 participants for analysis.During a median follow-up of6.5 years,387 non-CV deaths,173 CV deaths,645 nonfatal major adverse CV events(MACEs)and 368 hospitalizations for congestive heart failure(CHF)were observed.OPG and FGF23 were associated with all outcomes,with the highest hazard ratios(HRs)for OPG.In the final Cox regression model,adjusted for CV risk factors,including kidney function and all other investigated biomarkers,each standard deviation increase in OPG was associated with non-CV death(HR 1.76,95%CI:1.35–2.30),CV death(HR 2.18,95%CI:1.50–3.16),MACE(HR 1.38,95%CI:1.12–1.71)and hospitalization for CHF(HR 2.05,95%CI:1.56–2.69).Out of the nine biomarkers examined,stratification based on serum OPG best identified the CKD patients who were at the highest risk for any adverse CV outcome and mortality.

Does Current Nephrology Fellowship Training Affect Uti-lization of Peritoneal Dialysis in the United States?

Background: The 2010 US Renal Data System annual report revealed that peritoneal dialysis is used by only 7% of end-stage renal disease patients on chronic dialysis vs. hemodialysis which is used by 93% of such patients, despite documented benefits of peritoneal dialysis over hemodialysis in these cases. Purpose: We examined whether education of nephrology fellows contributed to underutilization of peritoneal dialysis in the US. Methods: Self-report questionnaires were administered electronically to nephrology fellowship training program directors, October 2010-March 2011 (55% response). Results: Median number of training faculty and patients/fellow were significantly lower for peritoneal-dialysis vs. hemodialysis training. Hours of didactic teaching for fellows over their 2-year training period were significantly lower for peritoneal dialysis vs. hemodialysis. Peritoneal dialysis training was 20% of total training vs. 80% for hemodialysis. Most program directors (87%) believed lack of trained faculty in peritoneal dialysis and insufficient peritoneal dialysis patient population contributed to inadequate fellows’ peritoneal dialysis training. Conclusions: Findings suggest that current nephrology fellowship training in peritoneal dialysis is inadequate and contributes to its underutilization.

Role of antidiabetic agents in type 2 diabetes patients with chronic kidney disease

Insulin resistance is a condition in which the target tissues have a decreased response to insulin signaling,resulting in glucose uptake defect,and an increased blood sugar level.Pancreatic beta cells thus enhance insulin production to compensate.This situation may cause further beta cell dysfunction and failure,which can lead diabetes mellitus(DM).Insulin resistance is thus an important cause of the development of type 2 DM.Insulin resistance has also been found to have a strong relationship with cardiovascular disease and is common in chronic kidney disease(CKD)patients.The mechanisms of insulin resistance in CKD are complex and multifactorial.They include physical inactivity,inflammation and oxidative stress,metabolic acidosis,vitamin D deficiency,adipose tissue dysfun-ction,uremic toxins,and renin-angiotensin-aldosterone system activation.Currently,available anti-diabetic agents,such as biguanides,sulfonylureas,thiazolidinediones,alfa-glucosidase inhibitors,glucagon-like peptide-1-based agents,and sodium-glucose co-transporter-2 inhibitors,have different effects on insulin resistance.In this short review,we describe the potential mechanisms of insulin resistance in CKD patients.We also review the interaction of currently available anti-diabetic medications with insulin resistance.

Effectiveness and safety of apixaban and rivaroxaban vs warfarin in patients with atrial fibrillation and chronic kidney disease

BACKGROUND Randomized controlled trials(RCTs)of direct oral anticoagulants(DOACs)included a low proportion of atrial fibrillation(AF)patients with chronic kidney disease(CKD),and suggested that DOACs are safe and effective in patients with mild-to-moderate CKD.In a metanalysis of RCTs and observational studies,DOACs were associated with better efficacy(vs warfarin)in early CKD and had similar efficacy and safety profiles in patients with stages IV-V CKD.But few studies have provided data on the safety and effectiveness of each DOAC vs warfarin in patients with stage III CKD.The effectiveness and safety of DOACs in those patients are still subject to debate.AIM To assess and compare the effectiveness and safety of apixaban and rivaroxaban vs warfarin in this patient population.METHODS A cohort of patients with an inpatient or outpatient code for AF and stage III CKD who were newly prescribed apixaban and rivaroxaban was created using the administrative databases from the Quebec province of Canada between 2013 and 2017.The primary effectiveness outcome was a composite of ischemic stroke,systemic embolism,and death,whereas the primary safety outcome was a composite of major bleeding within a year of DOAC vs warfarin initiation.Treatment groups were compared in an under-treatment analysis using inverse probability of treatment weighting and Cox proportional hazards.RESULTS A total of 8899 included patients filled out a new oral anticoagulation therapy claim;3335 for warfarin and 5564 for DOACs.Compared with warfarin,15 mg and 20 mg rivaroxaban presented a similar effectiveness and safety composite risk.Apixaban 5.0 mg was associated with a lower effectiveness composite risk[Hazard ratio(HR)0.76;95%confidence interval(CI):0.65-0.88]and a similar safety risk(HR 0.94;95%CI:0.66-1.35).Apixaban 2.5 mg was associated with a similar effectiveness composite(HR 1.00;95%CI:0.79-1.26)and a lower safety risk(HR 0.65;95%CI:0.43-0.99.Although,apixaban 5.0 mg was associated with a better effectiveness(HR 0.76;95%CI:0.65-0.88),but a similar safety risk profile(HR 0.94;95%CI:0.66-1.35).The observed improvement in the effectiveness composite for apixaban 5.0 mg was driven by a reduction in mortality(HR 0.61;95%CI:0.43-0.88).CONCLUSION In comparison with warfarin,rivaroxaban and apixaban appear to be effective and safe in AF patients with stage III CKD.

BK viral infection: A review of management and treatment

BK viral infection remains to be a challenging post-transplant infection,which can result in kidney dysfunction.The mainstay approach to BK infection is reduction of immunosuppression.Alterations in immunosuppressive regimen with minimization of calcineurin inhibitors,use of mechanistic target of rapamycin inhibitors,and leflunomide have been attempted with variable outcomes.Over the past few years,investigators have explored potential therapeutic options for BK infection.Fluoroquinolone prophylaxis and treatment was found to have no benefit in kidney transplant recipients.The utility of cidofovir is limited by its nephrotoxicity.Intravenous immunoglobulin is becoming a popular option for treatment and prophylaxis for BK infection,as it increases the neutralizing antibody titers against the most common BK virus serotypes.Virus-specific T cell therapy is an emerging treatment option for BK viremia.In this review,we will explore management and therapeutic options for BK infection and recent evidence available in literature.

Retrospective analysis of early COVID-19 vaccine efficacy in older individuals receiving primary cycle, first booster and second booster

Background:We analysed data garnered during the ongoing Italian nationwide coronavirus disease 2019(COVID-19)vaccination campaign for comparing early COVID-19 monovalent vaccine efficacy in older persons who received the primary vaccination cycle,the first vaccine booster,and the second vaccine booster.Methods:We conducted a retrospective analysis of early COVID-19 monovalent vaccine efficacy(i.e.,within 120 days)against COVID-19 related hospitalizations,intensive care unit(ICU)admissions and deaths in older persons(i.e.,aged≥80 years),by accessing official data of the COVID-19 national integrated surveillance program instituted by the Italian National Institute of Health.Vaccine efficacy was compared(odds ratio;OR)among cohorts receiving the primary vaccination cycle,the first vaccine booster,and the second vaccine booster.Results:A consistent decline could be seen in the rate of COVID-19 hospitalizations,ICU admissions and deaths with increasing number of monovalent immunizations.Within 120 days of administration,the first and second vaccine boosters had superior efficacy compared to the primary vaccination cycle,reducing the odds of all endpoints between 62%-71%and 69%-84%,respectively.A modestly superior early efficacy could also be noted for the second versus the first monovalent vaccine booster(ORs of all endpoints further reduced by 18%-48%).Conclusion:Since an increasing number of immunizations is associated with a lower risk of unfavourable COVID-19 outcomes,vaccine boosters may be useful for limiting the clinical burden of this infectious disease in elderly populations.

Harmonization of SARS-CoV-2 antigen immunoassays:are they measuring the same“thing”?

Background:This study was planned to assess the accuracy and comparability of two commercially available,laboratory-based SARS-CoV-2(severe acute respiratory syndrome)antigen(Ag)immunoassays.Methods:We studied a cohort of subjects with acute SARS-CoV-2 infection,from whom a nasopharyngeal swab was taken and tested with a molecular assay(Altona Diagnostics RealStar SARS-CoV-2 RT-PCR Kit)and two laboratory-based,fully automated SARS-CoV-2 Ag immunoassays(Fujirebio Lumipulse G SARS-CoV-2 Ag and Roche Elecsys SARS-CoV-2 Ag).Results:The final population consisted in 93 subjects testing positive for SARS-CoV-2 RNA,34 with cycle threshold(Ct)values<29.5.The results of the two SARS-CoV-2 Ag immunoassays were significantly intercorrelated(r=0.77;P<0.001)in the entire cohort,though such correlation considerably improved in patients with high viral load(cycle threshold values<29.5:r=0.96;P<0.001).The accuracy for identifying samples with high viral load was excellent for both Lumipulse G SARS-CoV-2 Ag(AUC,0.99;P<0.001)and Elecsys SARS-CoV-2 Ag(AUC,0.99;P<0.001),with best cut-offs of 2.03 ng/mL for Lumipulse G SARS-CoV-2 Ag(1.00 sensitivity and 0.88 specificity)and 0.70 COI for Elecsys SARS-CoV-2 Ag(1.00 sensitivity and 0.80 specificity),respectively.Conclusion:The results of this study provide valuable support to usability of fully-automated,rapid,high throughput and accurate SARS-CoV-2 Ag immunoassays for complementing molecular assays.

Pooled analysis of efficacy of the fourth mRNA-based COVID-19 vaccine dose in eliciting anti-SARS-CoV-2 serum antibody response in the general immunocompetent population

Objective:Since the opportunity of widespread administration of the fourth mRNA-based coronavirus disease 2019(COVID-19)vaccine dose remains controversial,this article provides a pooled analysis of the efficacy of the second COVID-19 mRNA-based homologous vaccine booster in eliciting anti-SARS-CoV-2 serum antibody response in general immunocompetent populations.Methods:We conducted a digital search in Medline using the keywords"fourth dose"or"second booster"and"antibodies"and"COVID-19"or"SARS-CoV-2"and"BNT162b2"or"mRNA-1273",to identify all clinical studies which evaluated the anti-SARS-CoV-2 serum antibody response after the fourth mRNA-based COVID-19 homologous vaccine dose administration in general immunocompetent populations compared to the response seen before its administration and after the first booster.Results:Four studies totaling 571 recipients of the second mRNA-based COVID-19 vaccine booster were finally included in our analysis.The weighted mean difference(WMD)ratio of anti-SARS-CoV-2 serum antibodies levels measured after and before administration of the fourth vaccine dose was 9.7(95%CI,6.5-12.9)in those receiving BNT162b2 and 12.0(95%CI,5.8-18.2)in those receiving mRNA-1273,respectively.The WMD ratio of anti-SARS-CoV-2 serum antibodies levels measured at the peak of the fourth and third vaccine doses was 1.4(95%CI,1.2-1.7)in those receiving BNT162b2 and 1.9(95%CI,1.5-2.4)in those receiving mRNA-1273,respectively.Conclusion:Our data confirm the efficacy of the fourth mRNA-based COVID-19 vaccine dose in restoring a satisfactory level of anti-SARS-CoV-2 serum antibodies,though such effectiveness seems only marginally superior to that of the first booster.