Serum Glial Fibrillary Acidic Protein and Neurofilament Light Chain Levels Reflect Different Mechanisms of Disease Progression under B-Cell Depleting Treatment in Multiple Sclerosis.

OBJECTIVE: To investigate the longitudinal dynamics of serum glial fibrillary acidic protein (sGFAP) and serum neurofilament light chain (sNfL) levels in people with multiple sclerosis (pwMS) under B-cell depleting therapy (BCDT) and their capacity to prognosticate future progression independent of relapse activity (PIRA) events. METHODS: A total of 362 pwMS (1,480 samples) starting BCDT in the Swiss Multiple Sclerosis (MS) Cohort were included. sGFAP levels in 2,861 control persons (4,943 samples) provided normative data to calculate adjusted Z scores. RESULTS: Elevated sGFAP levels (Z score >1) at 1 year were associated with a higher hazard for PIRA (hazard ratio [HR]: 1.80 [95% CI: 1.17-2.78]; p = 0.0079) than elevated sNfL levels (HR, 1.45 [0.95-2.24], p = 0.0886) in a combined model. Independent of PIRA events, sGFAP levels longitudinally increased by 0.49 Z score units per 10 years follow-up (estimate, 0.49 [0.29, 0.69], p < 0.0001). In patients experiencing PIRA, sGFAP Z scores were 0.52 Z score units higher versus stable patients (0.52 [0.22, 0.83], p = 0.0009). Different sNfL Z score trajectories were found in pwMS with versus without PIRA (interaction p = 0.0028), with an average decrease of 0.92 Z score units per 10 years observed without PIRA (-0.92 [-1.23, -0.60], p < 0.0001), whereas levels in patients with PIRA remained high. INTERPRETATION: Elevated sGFAP and lack of drop in sNfL after BCDT start are associated with increased risk of future PIRA. These findings provide a rationale for combined monitoring of sNfL and sGFAP in pwMS starting BCDT to predict the risk of PIRA, and to use sGFAP as an outcome in clinical trials aiming to impact on MS progressive disease biology. ANN NEUROL 2024.

External validation of the 0/1h-algorithm and derivation of a 0/2h-algorithm using a new point-of-care Hs-cTnI assay.

BACKGROUND: The high-sensitivity cardiac troponin (hs-cTn) I point-of-care (POC) hs-cTnI-PATHFAST assay has recently become clinically available. METHODS: We aimed to externally validate the hs-cTnI-PATHFAST 0/1h-algorithm recently developed for the early diagnosis of non-ST-segment-elevation myocardial infarction (NSTEMI) and derive and validate a 0/2-algorithm in patients presenting to the emergency department with acute chest discomfort included in a multicenter diagnostic study. Two independent cardiologists centrally adjudicated the final diagnoses using all the clinical and study-specific information available including serial measurements of hs-cTnI-Architect. RESULTS: Among 1,532 patients (median age 60 years, 33% [n = 501] women), NSTEMI was the final diagnosis in 13%. External validation of the hs-cTnI-PATHFAST 0/1h-algorithm showed very high negative predictive value (NPV; 100% [95%CI, 99.5%-100%]) and sensitivity 100% (95%CI, 98.2%-100%) for rule-out of NSTEMI. Positive predictive value (PPV) and specificity for rule-in of NSTEMI were high (74.9% [95%CI, 68.3%-80.5%] and 96.4% [95%CI, 95.2%-97.3%], respectively). Among 1,207 patients (median age 61 years, 32% [n = 391] women) available for the derivation (n = 848) and validation (n = 359) of the hs-cTnI-PATHFAST 0/2h-algorithm, a 0h-concentration <3 ng/L or a 0h-concentration <4 ng/L with a 2h-delta <4ng/L ruled-out NSTEMI in 52% of patients with a NPV of 100% (95%CI, 98-100) and sensitivity of 100% (95%CI, 92.9%-100%) in the validation cohort. A 0h-concentration ≥90ng/L or a 2h-delta ≥ 55ng/L ruled-in 38 patients (11%): PPV 81.6% (95%CI, 66.6-90.8), specificity 97.7% (95%CI, 95.4-98.9%). CONCLUSIONS: The POC hs-cTnI-PATHFAST assay allows rapid and effective rule-out and rule-in of NSTEMI using both a 0/1h- and a 0/2h-algorithm with high NPV/sensitivity for rule-out and high PPV/specificity for rule-in. CLINICAL TRIAL REGISTRATION: NCT00470587.

Potent neutralization by monoclonal human IgM against SARS-CoV-2 is impaired by class switch.

To investigate the class-dependent properties of anti-viral IgM antibodies, we use membrane antigen capture activated cell sorting to isolate spike-protein-specific B cells from donors recently infected with SARS-CoV-2, allowing production of recombinant antibodies. We isolate 20, spike-protein-specific antibodies of classes IgM, IgG, and IgA, none of which shows any antigen-independent binding to human cells. Two antibodies of class IgM mediate virus neutralization at picomolar concentrations, but this potency is lost following artificial switch to IgG. Although, as expected, the IgG versions of the antibodies appear to have lower avidity than their IgM parents, this is not sufficient to explain the loss of potency.

Association of preoperative beta-blocker use and cardiac complications after major noncardiac surgery: a prospective cohort study.

INTRODUCTION: Cardiac complications after major noncardiac surgery are common and associated with high morbidity and mortality. How preoperative use of beta-blockers may impact perioperative cardiac complications remains unclear. METHODS: In a multicentre prospective cohort study, preoperative beta-blocker use was ascertained in consecutive patients at elevated cardiovascular risk undergoing major noncardiac surgery. Cardiac complications were prospectively monitored and centrally adjudicated by two independent experts. The primary endpoint was perioperative myocardial infarction or injury attributable to a cardiac cause (cardiac PMI) within the first three postoperative days. The secondary endpoints were major adverse cardiac events (MACE), defined as a composite of myocardial infarction, acute heart failure, life-threatening arrhythmia, and cardiovascular death and all-cause death after 365 days. We used inverse probability of treatment weighting to account for differences between patients receiving beta-blockers and those who did not. RESULTS: A total of 3839/10 272 (37.4%) patients (mean age 74 yr; 44.8% female) received beta-blockers before surgery. Patients on beta-blockers were older, and more likely to be male with established cardiorespiratory and chronic kidney disease. Cardiac PMI occurred in 1077 patients, with a weighted odds ratio of 1.03 (95% confidence interval [CI] 0.94-1.12, P=0.55) for patients on beta-blockers. Within 365 days of surgery, 971/10 272 (9.5%) MACE had occurred, with a weighted hazard ratio of 0.99 (95% CI 0.83-1.18, P=0.90) for patients on beta-blockers. CONCLUSION: Preoperative use of beta-blockers was not associated with decreased cardiac complications including cardiac perioperative myocardial infarction or injury and major adverse cardiac event. Additionally, preoperative use of beta-blockers was not associated with increased all-cause death within 30 and 365 days. CLINICAL TRIAL REGISTRATION: NCT02573532.

Impact of Additional Administration of von Willebrand Factor Concentrates to Thrombocyte Transfusion in Perioperative Bleeding in Cardiac Surgery.

Background: Von Willebrand factor (vWF) is an important part of blood coagulation since it binds platelets to each other and to endothelial cells. In traumatic and surgical haemorrhage, both blood cells and plasmatic factors are consumed, leading to consumption coagulopathy and fluid resuscitation. This often results in large amounts of crystalloids and blood products being infused. Additional administration of vWF complex and platelets might mitigate this problem. We hypothesize that administration of vWF concentrate additionally to platelet concentrates reduces blood loss and the amount of blood products (platelets, red blood cells [RBC], fresh frozen plasma [FFP]) administered. Methods: We conducted a monocentric 6-year retrospective data analysis of cardiac surgery patients. Included were all patients receiving platelet concentrates within 48 h postoperatively. Patients who additionally received vWF concentrates were allocated to the intervention group and all others to the control group. Groups were compared in mixed regression models correcting for known confounders, based on nearest neighbour propensity score matching. Primary endpoints were loss of blood (day one and two) and amount of needed blood products on day one and two (platelets, RBC, FFP). Secondary endpoints were intensive care unit (ICU) and in-hospital length of stay, ICU and in-hospital mortality, and absolute difference of platelet counts before and after treatment. Results: Of 497 patients analysed, 168 (34%) received vWF concentrates. 121 patients in both groups were considered for nearest neighbour matching. Patients receiving additional vWF were more likely to receive more blood products (RBC, FFP, platelets) in the first 24 h after surgery and had around 200 mL more blood loss at the same time. Conclusion: In this retrospective analysis, no benefit in additional administration of vWF to platelet concentrates on perioperative blood loss, transfusion requirement (platelets, RBC, FFP), length of stay, and mortality could be found. These findings should be verified in a prospective randomized controlled clinical trial (www.clinicaltrials.gov identifier NCT04555785).

Diagnostic discrimination of a novel high-sensitivity cardiac troponin I assay and derivation/validation of an assay-specific 0/1h-algorithm.

BACKGROUND: We aimed to assess the diagnostic utility of the Dimension EXL LOCI High-Sensitivity Troponin I (hs-cTnI-EXL) assay. METHODS: This multicenter study included patients with chest discomfort presenting to the emergency department. Diagnoses were centrally and independently adjudicated by two cardiologists using all available clinical information. Adjudication was performed twice including serial measurements of high-sensitivity cardiac troponin (hs-cTn) I-Architect (primary analysis) and serial measurements of hs-cTnT-Elecsys (secondary analysis) in addition to the clinically used (hs)-cTn. The primary objective was to assess and compare the discriminatory performance of hs-cTnI-EXL, hs-cTnI-Architect and hs-cTnT-Elecsys for acute myocardial infarction (MI). Furthermore, we derived and validated a hs-cTnI-EXL-specific 0/1h-algorithm. RESULTS: Adjudicated MI was the diagnosis in 204/1454 (14%) patients. The area under the receiver operating characteristics curve for hs-cTnI-EXL was 0.94 (95%CI, 0.93-0.96), and comparable to hs-cTnI-Architect (0.95; 95%CI, 0.93-0.96) and hs-cTnT-Elecsys (0.93; 95%CI, 0.91-0.95). In the derivation cohort (n = 813), optimal criteria for rule-out of MI were <9ng/L at presentation (if chest pain onset >3h) or <9ng/L and 0h-1h-change <5ng/L, and for rule-in ≥160ng/L at presentation or 0h-1h-change ≥100ng/L. In the validation cohort (n = 345), these cut-offs ruled-out 56% of patients (negative predictive value 99.5% (95%CI, 97.1-99.9), sensitivity 97.8% (95%CI, 88.7-99.6)), and ruled-in 9% (positive predictive value 83.3% (95%CI, 66.4-92.7), specificity 98.3% (95%CI, 96.1-99.3)). Secondary analyses using adjudication based on hs-cTnT measurements confirmed the findings. CONCLUSIONS: The overall performance of the hs-cTnI-EXL was comparable to best-validated hs-cTnT/I assays and an assay-specific 0/1h-algorithm safely rules out and accurately rules in acute MI. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov number, NCT00470587.

Treatment Strategies in Anemic Patients Before Cardiac Surgery.

Both preoperative anemia and the transfusion of red blood cells have been associated with increased morbidity and mortality after cardiac surgery. To reduce the need for blood transfusion during surgery and improve patient outcomes, patient blood management programs have been developed. A primary focus of patient blood management in the preoperative period is the identification, diagnosis, and treatment of preoperative anemia, as anemia is associated with an increased risk of preoperative blood transfusion. In this narrative review, the authors focus on the laboratory screening of anemia before surgery and the evidence and limitations of different treatment strategies in anemic patients scheduled for cardiac surgery. To accurately correct preoperative anemia, the timely detection and definition of the etiology of anemia before elective cardiac surgery are crucial. Multiple randomized studies have been performed using preoperative iron supplementation and/or administration of erythropoiesis-stimulating agents in patients undergoing cardiac surgery. Although preoperative iron substitution in patients with iron deficiency is recommended, the evidence of its effectiveness is limited. In patients with nonpure iron deficiency anemia, combined therapy with erythropoiesis-stimulating agents and intravenous iron is recommended. Combined therapy might effectively reduce the need for red blood cell transfusion, even if applied shortly before cardiac surgery. The therapeutic effect on morbidity and mortality remains unclear. Nonetheless, the timely preoperative assessment of anemia and determination of iron status, eventually leading to targeted therapy, should become a standard of care and might potentially improve patient outcomes.

International Validation of the Canadian Syncope Risk Score : A Cohort Study.

BACKGROUND: The Canadian Syncope Risk Score (CSRS) was developed to predict 30-day serious outcomes not evident during emergency department (ED) evaluation. OBJECTIVE: To externally validate the CSRS and compare it with another validated score, the Osservatorio Epidemiologico della Sincope nel Lazio (OESIL) score. DESIGN: Prospective cohort study. SETTING: Large, international, multicenter study recruiting patients in EDs in 8 countries on 3 continents. PARTICIPANTS: Patients with syncope aged 40 years or older presenting to the ED within 12 hours of syncope. MEASUREMENTS: Composite outcome of serious clinical plus procedural events (primary outcome) and the primary composite outcome excluding procedural interventions (secondary outcome). RESULTS: Among 2283 patients with a mean age of 68 years, the primary composite outcome occurred in 7.2%, and the composite outcome excluding procedural interventions occurred in 3.1% at 30 days. Prognostic performance of the CSRS was good for both 30-day composite outcomes and better compared with the OESIL score (area under the receiver-operating characteristic curve [AUC], 0.85 [95% CI, 0.83 to 0.88] vs. 0.74 [CI, 0.71 to 0.78] and 0.80 [CI, 0.75 to 0.84] vs. 0.69 [CI, 0.64 to 0.75], respectively). Safety of triage, as measured by the frequency of the primary composite outcome in the low-risk group, was higher using the CSRS (19 of 1388 [0.6%]) versus the OESIL score (17 of 1104 [1.5%]). A simplified model including only the clinician classification of syncope (cardiac syncope, vasovagal syncope, or other) variable at ED discharge-a component of the CSRS-achieved similar discrimination as the CSRS (AUC, 0.83 [CI, 0.80 to 0.87] for the primary composite outcome). LIMITATION: Unable to disentangle the influence of other CSRS components on clinician classification of syncope at ED discharge. CONCLUSION: This international external validation of the CSRS showed good performance in identifying patients at low risk for serious outcomes outside of Canada and superior performance compared with the OESIL score. However, clinician classification of syncope at ED discharge seems to explain much of the performance of the CSRS in this study. The clinical utility of the CSRS remains uncertain. PRIMARY FUNDING SOURCE: Swiss National Science Foundation & Swiss Heart Foundation.

Does the age of packed red blood cells, donor sex or sex mismatch affect the sublingual microcirculation in critically ill intensive care unit patients? A secondary interpretation of a retrospective analysis.

In vitro studies have thoroughly documented age-dependent impact of storage lesions in packed red blood cells (pRBC) on erythrocyte oxygen carrying capacity. While studies have examined the effect of pRBC age on patient outcome only few data exist on the microcirculation as their primary site of action. In this secondary analysis we examined the relationship between age of pRBC and changes of microcirculatory flow (MCF) in 54 patients based on data from the Basel Bedside assessment Microcirculation Transfusion Limit study (Ba2MiTraL) on effects of pRBC on sublingual MCF. Mean change from pre- to post-transfusion proportion of perfused vessels (∆PPV) was + 8.8% (IQR - 0.5 to 22.5), 5.5% (IQR 0.1 to 10.1), and + 4.7% (IQR - 2.1 to 6.5) after transfusion of fresh (≤ 14 days old), medium (15 to 34 days old), and old (≥ 35 days old) pRBC, respectively. Values for the microcirculatory flow index (MFI) were + 0.22 (IQR - 0.1 to 0.6), + 0.22 (IQR 0.0 to 0.3), and + 0.06 (IQR - 0.1 to 0.3) for the fresh, medium, and old pRBC age groups, respectively. Lower ∆PPV and transfusion of older blood correlated with a higher Sequential Organ Failure Assessment (SOFA) score of patients upon admission to the intensive care unit (ICU) (p = 0.01). However, regression models showed no overall significant correlation between pRBC age and ∆PPV (p = 0.2). Donor or recipient sex had no influence. We detected no significant effect of pRBC on microcirculation. Patients with a higher SOFA score upon ICU admission might experience a negative effect on the ∆PPV after transfusion of older blood.

Safety and Feasibility of Immunoadsorption with Heparin Anticoagulation in Preparation of ABO-Incompatible Kidney Transplantation: A Retrospective Single-Center Study.

Introduction: Immunoadsorption (IA) of isohemagglutinins is an often-crucial procedure in preparation of major ABO blood group-incompatible living donor kidney transplantation (ABOi LDKT). Standard citrate-based anticoagulation during the procedure has potential disadvantages for distinct patient groups. In this study, we report our experience with an alternative anticoagulation scheme using heparin during IA for selected patients. Methods: We conducted a retrospective analysis of all patients who underwent IA with heparin anticoagulation between February 2013 and December 2019 at our institution with focus on the safety and efficacy of the adapted procedure. For further validation, we compared graft function, graft survival, and overall survival with those of all recipients of living donor kidney transplants with or without pretransplant desensitizing apheresis for ABO antibodies at our institution during the same period. Results: In thirteen consecutive patients prepared for ABOi LDKT with IA with heparin anticoagulation, no major bleeding or other significant complications were observed. All patients achieved sufficient isohemagglutinin titer reduction to proceed to transplant surgery. Graft function, graft survival, and overall survival did not significantly differ from patients treated with standard anticoagulation for IA or ABO compatible recipients of living donor kidneys. Conclusion: IA with heparin in preparation of ABOi LDKT is safe and feasible for selected patients after internal validation.

Indices of iron homeostasis in asymptomatic subjects with HFE mutations and moderate ferritin elevation during iron removal treatment.

We analysed iron biomarkers and their relationships in 30 subjects with HFE mutations and moderate hyperferritinaemia undergoing iron removal at our blood donation centre. Body mass index (BMI) and liver enzymes were assessed. Serum iron (SI), ferritin, transferrin saturation (TSAT), hepcidin and non-transferrin bound iron (NTBI) were measured serially. Seventeen subjects had p.C282Y/p.C282Y, nine p.C282Y/p.H63D, four p.H63D/p.H63D. Median age (p = 0.582), BMI (p = 0.500) and ferritin (p = 0.089) were comparable. At baseline, 12/17 p.C282Y/p.C282Y and 2/9 p.C282Y/p.H63D had measurable NTBI (p = 0.003). The p.C282Y/p.C282Y had higher TSAT (p < 0.001), lower hepcidin (p = 0.031) and hepcidin/ferritin ratio (p = 0.073). After treatment, iron indices were similar among groups, except TSAT (higher in p.C282Y/p.C282Y; p = 0.06). Strong relationships were observed between ferritin and TSAT (R = 0.71), NTBI and TSAT (R = 0.61), NTBI and SI (R = 0.54) in p.C282Y/p.C282Y. Hepcidin correlated weakly with ferritin in p.C282Y/p.C282Y (R = 0.37) but strongly in p.C282Y/p.H63D (R = 0.66) and p.H63D/p.H63D (R = 0.72), while relationships with TSAT were weak (R = 0.27), moderate (R = 0.55) and strong (R = 0.61), respectively. Low penetrance p.C282Y/p.C282Y phenotype displays hepcidin dysregulation and biochemical risk for iron toxicity.

Characterising the epidemic spread of influenza A/H3N2 within a city through phylogenetics.

Infecting large portions of the global population, seasonal influenza is a major burden on societies around the globe. While the global source sink dynamics of the different seasonal influenza viruses have been studied intensively, its local spread remains less clear. In order to improve our understanding of how influenza is transmitted on a city scale, we collected an extremely densely sampled set of influenza sequences alongside patient metadata. To do so, we sequenced influenza viruses isolated from patients of two different hospitals, as well as private practitioners in Basel, Switzerland during the 2016/2017 influenza season. The genetic sequences reveal that repeated introductions into the city drove the influenza season. We then reconstruct how the effective reproduction number changed over the course of the season. While we did not find that transmission dynamics in Basel correlate with humidity or school closures, we did find some evidence that it may positively correlated with temperature. Alongside the genetic sequence data that allows us to see how individual cases are connected, we gathered patient information, such as the age or household status. Zooming into the local transmission outbreaks suggests that the elderly were to a large extent infected within their own transmission network. In the remaining transmission network, our analyses suggest that school-aged children likely play a more central role than pre-school aged children. These patterns will be valuable to plan interventions combating the spread of respiratory diseases within cities given that similar patterns are observed for other influenza seasons and cities.

Characterization of pathogen-inactivated COVID-19 convalescent plasma and responses in transfused patients.

BACKGROUND: Efficacy of donated COVID-19 convalescent plasma (dCCP) is uncertain and may depend on antibody titers, neutralizing capacity, timing of administration, and patient characteristics. STUDY DESIGN AND METHODS: In a single-center hypothesis-generating prospective case-control study with 1:2 matched dCCP recipients to controls according to disease severity at day 1, hospitalized adults with COVID-19 pneumonia received 2 × 200 ml pathogen-reduced treated dCCP from 2 different donors. We evaluated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in COVID-19 convalescent plasma donors and recipients using multiple antibody assays including a Coronavirus antigen microarray (COVAM), and binding and neutralizing antibody assays. Outcomes were dCCP characteristics, antibody responses, 28-day mortality, and dCCP -related adverse events in recipients. RESULTS: Eleven of 13 dCCPs (85%) contained neutralizing antibodies (nAb). PRT did not affect dCCP antibody activity. Fifteen CCP recipients and 30 controls (median age 64 and 65 years, respectively) were enrolled. dCCP recipients received 2 dCCPs from 2 different donors after a median of one hospital day and 11 days after symptom onset. One dCCP recipient (6.7%) and 6 controls (20%) died (p = 0.233). We observed no dCCP-related adverse events. Transfusion of unselected dCCP led to heterogeneous SARS CoV-2 antibody responses. COVAM clustered dCCPs in 4 distinct groups and showed endogenous immune responses to SARS-CoV-2 antigens over 14-21 days post dCCP in all except 4 immunosuppressed recipients. DISCUSSION: PRT did not impact dCCP anti-virus neutralizing activity. Transfusion of unselected dCCP did not impact survival and had no adverse effects. Variable dCCP antibodies and post-transfusion antibody responses indicate the need for controlled trials using well-characterized dCCP with informative assays.

Preoperative anaemia in cardiac surgery: preoperative assessment, treatment and outcome.

Preoperative anaemia is common and associated with increased postoperative morbidity and mortality after cardiac surgery. These findings are supported by a large Dutch cohort study including >35 000 patients published in this issue of the British Journal of Anaesthesia. Timely diagnosis and preoperative anaemia treatment seem to be reasonable targets for perioperative risk stratification and modification. However, implementation of anaemia therapy into clinical routines remains challenging, and evidence for improved outcome is currently limited.

Frequency, reactivity and evolution of human leukocyte antigen and human platelet antigen antibodies in the setting of hematopoietic cell transplantation.

BACKGROUND AND OBJECTIVES: Antibodies (Ab) against HLA and HPA antigens play an important role in HCT. In this prospective study we evaluated prevalence and kinetics of HLA- and HPA-Ab after HCT, including a possible donor-recipient transfer and their clinical relevance in respect to platelet transfusion refractoriness (PTR). MATERIALS AND METHODS: Patients were consecutively recruited. Ab were determined by microbead assay technique and a mean fluorescence intensity cut-off of 1,000. RESULTS: At baseline, 21 donors (42 %) and 27 patients (54 %) had HLA-Ab with a mean panel reactivity (cPRA) of 34.9 ± 29.4 % and 46.1 ± 36.5 %, respectively. We observed a significant higher number of HLA-Ab specificities in female donors and patients and a predominance of HLA-class I Ab. At day 0 we detected an increase of HLA-Ab (from 526 to 673) and cPRA (55.2 ± 31.9 %). Thirty-six patients (72 %) developed new HLA-Ab, mainly 3 weeks after HCT. In 7 patients an HLA-Ab with the same specificity as detected in the corresponding donor emerged, suggesting a possible transfer from the donor to the recipient. Overall, MFI showed a high variation. Type and number of transfusions were not associated with number and intensity of HLA-Ab (ρ: -0.05 - 0.02). Number of HLA-Ab, cPRA and intensity were not associated with PTR, which occurred in 9 patients (18 %) and none had bleeding WHO > 2. CONCLUSIONS: Although a considerable number of patients have and develop HLA-Ab before and early after HCT, we found no association with PTR and bleeding and management should be individualized.

Pathogen inactivation treatment of triple-dose apheresis platelets with amotosalen and ultraviolet a light.

BACKGROUND: A triple storage (TS) set allows for pathogen inactivation (PI) treatment of triple-dose apheresis platelet products with amotosalen + UVA. We evaluated the quality and metabolic parameters of platelet concentrates (PCs) pathogen inactivated and stored for 7 days. MATERIALS AND METHODS: Twelve triple-dose products collected with two different apheresis platforms were treated with amotosalen+UVA. Products were split into three single-dose units. Testing was made pretreatment, after splitting, at days 5 and 7 of storage. RESULTS: Single-dose PI PCs had a mean platelet content of 2.89 ± 0.35 x 1011 . From baseline to day 7, pH remained stable (7.1 ± 0.1 vs. 7.0 ± 0.1), pO2 increased (11.3 ± 2.4 vs. 18.3 ± 3.5 kPa) as did LDH (201 ± 119 vs. 324 ± 203 U/L) and lactate (3.6 ± 1.7 vs. 12.1 ± 1.5 mmol/L) (all p < 0.01); pCO2 decreased (4.1 ± 0.8 vs. 1.5 ± 0.7 mmHg; p < 0.01) and so did bicarbonate (6.6 ± 1.1 vs. 2.5 ± 1.4 mmol/L), glucose (5.6 ± 1.2 vs. 0.4 ± 0.4 mmol/L) and ATP (3.4 ± 0.9 vs. 2.5 ± 1.4 nmol/108 platelets) (all p < 0.05). CONCLUSION: Triple-dose PCs processed with the TS sets fulfilled the quality requirements and displayed metabolic changes of expected extent during 7-day storage.

Controversies in the Clinical Practice of Patient Blood Management.

Patient blood management (PBM) has been proposed as a standard of care in modern perioperative medicine. PBM-related interventions usually are implemented as bundles, but randomized controlled trials on the implementation of PBM as a bundle are missing. This special article focuses on the current evidence and controversies in the clinical practice of PBM and on emerging data related to specific PBM-related interventions in patients undergoing cardiac surgery. Strong evidence for many PBM-related interventions is limited because of missing studies or the poor quality of published findings and study endpoints. Restrictive blood transfusion and timely interventions to maintain hemoglobin concentration and to reduce blood loss potentially might result in improved patient outcome, although the latter has yet to be proven.

Long-Term Course of Haemoglobin and Ferritin Values in High-Frequency Donors of Whole Blood and Double Erythrocyte Apheresis.

BACKGROUND: High-intensity donation is a risk factor for iron deficiency in blood donors. Interdonation intervals for whole blood (WB) donation and double unit red blood cell apheresis (2RBC) vary among countries. We retrospectively evaluated the course of haemoglobin (Hb) and ferritin values in men regularly donating WB 4 times a year or 2RBC twice a year (i.e., maximal frequency) over a period of 48 months. METHODS: Data of male donors with 16 WB or 8 2RBC consecutive donations were analysed. The minimum Hb levels for WB donation and 2RBC apheresis (collection of 360 mL RBC) were 135 and 140 g/L, respectively. There was no lower limit set for ferritin, and no iron was substituted. RESULTS: We identified 294 WB (mean age 53 years, SD 11) and 151 2RBC donors (mean age 48 years, SD 9) who donated at a mean interval of 97 (SD 18) and 201 days (SD 32), respectively, between January 1, 2008, and December 31, 2013. At baseline, Hb and ferritin values were lower in WB donors compared to 2RBC donors, with a mean Hb of 153 g/L (SD 13) versus 159 g/L (SD 8) and a mean ferritin of 44 µg/L (SD 52) versus 73 µg/L (SD 56; p < 0.001 for both parameters), respectively. Ferritin was below 15 µg/L in 40 WB (14%) and in 4 (3%) 2RBC donors. In WB donors, the mean Hb levels at baseline versus last donation showed no significant difference (153 vs. 152 g/L, p = 0.068), whereas the mean ferritin levels decreased significantly (44 vs. 35 µg/L, p < 0.001). The 2RBC donor group displayed a statistically different decrease in both the mean Hb levels (158 vs. 157 g/L; p < 0.05) and the mean ferritin levels (73 vs. 66 µg/L; p = 0.052). The lowest Hb was measured at the 11th WB donation (152 g/L; p < 0.05) and at the 4th 2RBC apheresis (157 g/L; p < 0.05). There was no deferral due to low Hb at any time. The lowest ferritin was shown at the 4th WB (37 µg/L) and at the 3rd 2RBC donation (60 µg/L), respectively. At the last visit, ferritin was below 15 µg/L in 23 WB donors (8%) and in 2 2RBC donors (1%). CONCLUSIONS: High-intensity male donors with an interdonation interval of 12 weeks for WB donation and 24 weeks for 2RBC apheresis maintain acceptable Hb levels and, after an initial decline, stable ferritin levels despite ongoing blood donation.

Circulatory Neutrophils Exhibit Enhanced Neutrophil Extracellular Trap Formation in Early Puerperium: NETs at the Nexus of Thrombosis and Immunity.

Pregnancy is associated with elevated maternal levels of cell-free DNA of neutrophil extracellular trap (NET) origin, as circulatory neutrophils exhibit increased spontaneous NET formation, mainly driven by G-CSF and finely modulated by sex hormones. The postpartum period, on the other hand, involves physiological alterations consistent with the need for protection against infections and fatal haemorrhage. Our findings indicate that all relevant serum markers of neutrophil degranulation and NET release are substantially augmented postpartum. Neutrophil pro-NETotic activity in vitro is also upregulated particularly in post-delivery neutrophils. Moreover, maternal puerperal neutrophils exhibit a strong pro-NETotic phenotype, associated with increased levels of all key players in the generation of NETs, namely citH3, MPO, NE, and ROS, compared to non-pregnant and pregnant controls. Intriguingly, post-delivery NET formation is independent of G-CSF in contrast to late gestation and complemented by the presence of TF on the NETs, alterations in the platelet activity status, and activation of the coagulation cascade, triggered by circulating microparticles. Taken together, our results reveal the highly pro-NETotic and potentially procoagulant nature of postpartum neutrophils, bridging an overt immune activation with possible harmful thrombotic incidence.

Variations in hemoglobin measurement and eligibility criteria across blood donation services are associated with differing low-hemoglobin deferral rates: a BEST Collaborative study.

BACKGROUND: Determination of blood donor hemoglobin (Hb) levels is a pre-requisite to ensure donor safety and blood product quality. We aimed to identify Hb measurement practices across blood donation services and to what extent differences associate with low-Hb deferral rates. METHODS: An online survey was performed among Biomedical Excellence for Safer Transfusion (BEST) Collaborative members, extended with published data. Multivariable negative-binomial regression models were built to estimate adjusted associations of minimum donation intervals, Hb cut-offs (high, ≥13.5 g/dL in men or ≥ 12.5 g/dL in women, vs. lower values), iron monitoring (yes/no), providing or prescribing iron supplementation (yes/no), post-versus pre-donation Hb measurement and geographical location (Asian vs. rest), with low-Hb deferral rates. RESULTS: Data were included from 38 blood services. Low-Hb deferral rates varied from 0.11% to 8.81% among men and 0.84% to 31.85% among women. Services with longer minimum donation intervals had significantly lower deferral rates among both women (rate ratio, RR 0.53, 95%CI 0.33-0.84) and men (RR 0.53, 95%CI 0.31-0.90). In women, iron supplementation was associated with lower Hb deferral rates (RR 0.47, 95%CI 0.23-0.94). Finally, being located in Asia was associated with higher low-Hb deferral rates; RR 9.10 (95%CI 3.89-21.27) for women and 6.76 (95%CI 2.45-18.68) for men. CONCLUSION: Differences in Hb measurement and eligibility criteria, particularly longer donation intervals and iron supplementation in women, are associated with variations in low-Hb deferral rates. These insights could help improve both blood donation service efficiency and donor care.