How do you… decide which platelet bacterial risk mitigation strategy to select for your hospital-based transfusion service?
Ontology highlight
ABSTRACT:
SUBMITTER: Lu W
PROVIDER: S-EPMC7131880 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:Platelet transfusion can elicit alloimmune responses leading to alloantibody formation against donor-specific polymorphic residues, ultimately resulting in platelet transfusion refractoriness. Universal leukoreduction significantly reduced the frequency of alloimmunization after platelet transfusion, thereby showing the importance of white blood cells (WBCs) in inducing this alloresponse. It is, however, unknown if the residual risk for alloimmunization is caused by WBCs remaining after leukoreduction or if alloimmunization can be induced by platelets themselves. This study investigated the capacity of platelets to induce alloimmunization and identified potential product-related risk factors for alloimmunization. First, internalization of allogeneic platelets by dendritic cells (DCs) was demonstrated by confocal microscopy. Second, after internalization, presentation of platelet-derived peptides was shown by mass spectrometry analysis of human leukocytes antigen (HLA)-DR eluted peptides. Third, platelet-loaded DCs induced platelet-specific CD4 T cell responses. Altogether, this indicates a platelet-specific ability to induce alloimmunization. Therefore, factors enhancing platelet internalization may be identified as risk factor for alloimmunization by platelet concentrates. To investigate if storage of platelets is such a risk factor, internalization of stored platelets was compared with fresh platelets and showed enhanced internalization of stored platelets. Storage-induced apoptosis and accompanied phosphatidylserine exposure seemed to be instrumental for this. Indeed, DCs pre-incubated with apoptotic platelets induced the strongest IFN-γ production by CD4 T cells compared with pre-incubation with untreated or activated platelets. In conclusion, this study shows the capacity of platelets to induce platelet-specific alloimmune responses. Furthermore, storage-induced apoptosis of platelets is identified as potential risk factor for alloimmunization after platelet transfusions.
| S-EPMC6008548 | biostudies-literature
Project description:A majority of human therapeutic antibody candidates show pharmacokinetic properties suitable for clinical use, but an unexpectedly fast antibody clearance is sometimes observed that may limit the clinical utility. Pharmacokinetic data in cynomolgus monkeys collected for a panel of 52 antibodies showed broad distribution of target-independent clearance values (2.4-61.3 mL/day/kg), with 15 (29%) having clearance > 10 mL/day/kg. Alteration in the interaction with the recycling FcRn receptor did not account for the faster than expected clearance observed for the antibodies; off-target binding was presumed to account for the fast clearance. We developed an assay based on ELISA detection of non-specific binding to baculovirus particles that can identify antibodies having increased risk for fast clearance. This assay can be used during lead generation or optimization to identify antibodies with increased risk of having fast clearance in both humans and cynomolgus monkeys, and thus increase the likelihood of obtaining a suitable drug candidate.
| S-EPMC3502242 | biostudies-literature
Project description:Importance:Transmucosal immediate-release fentanyl (TIRF) drugs are potent, rapid-acting opioids approved to treat breakthrough pain in patients with cancer who are tolerant to other around-the-clock opioid analgesics. In March 2012, a US Food and Drug Administration-approved Risk Evaluation and Mitigation Strategy (REMS) was implemented, mandating prescribers, distributors, pharmacies, and patients to enroll in the REMS to prescribe, dispense, or receive TIRF drugs. Objective:To evaluate the association of the TIRF-REMS Access Program with TIRF prescribing. Design, Setting, and Participants:Cohort study using an interrupted time series analysis of TIRF prescriptions to Medicare Part D beneficiaries nationwide from 2010 to 2014. Data were analyzed from August 2017 through July 2018. Main Outcomes and Measures:Prescribing of TIRF per 100 000 Medicare Part D beneficiaries, overall and stratified by cancer status; percentage of TIRF prescriptions for patients without cancer, overall and by brand; and percentage of TIRF prescriptions for patients without known opioid tolerance, defined as patients prescribed at least 60 morphine milligram equivalents per day, overall and by brand. Results:There were 99 601 TIRF prescriptions written by 8619 clinicians to 10 472 patients. Most of the patients (79%) were younger than 65 years (mean [SD] age, 56 [13] years), and most (67%) did not have cancer. Implementation of TIRF-REMS was associated with a 26.7% relative level decrease in TIRF prescribing (95% CI, -33.3% to -19.4%; P < .001) but was followed by 2.0% monthly increases in prescribing (95% CI, 1.3% to 2.7%; P < .001). Sensitivity analyses that accounted for overall opioid prescribing trends were consistent with these findings. Furthermore, there were no significant changes associated with REMS implementation in the level (0.47%; 95% CI, -5.36% to 4.69%; P = .85) or trend (0.16%; 95% CI, -0.06% to 0.37%; P = .15) of the percentage of prescriptions for patients without cancer. However, a sensitivity analysis that used a broader cancer definition found implementation was associated with a 7.2% (95% CI, -13.5% to -0.48%; P = .04) level decrease in the percentage of TIRF prescriptions for patients without cancer. Lastly, the TIRF-REMS was associated with a 22.5% level decline in the percentage of TIRF prescriptions for patients without known opioid tolerance (95% CI, -36.1% to -5.95%; P = .01) followed by 1.98% monthly decreases (95% CI, -3.19% to -0.80%; P = .001). Conclusions and Relevance:Implementation of the TIRF-REMS Access Program, a restrictive drug distribution program, was associated with a temporary reduction in the rate of TIRF prescribing to Medicare Part D beneficiaries, and with a sustained decrease in the percentage of TIRF prescriptions for patients without known opioid tolerance. Implementation may have also been associated with a temporary decrease in the percentage of TIRF prescriptions for patients without cancer.
| S-EPMC6450314 | biostudies-other
Project description: Not available
| S-EPMC8242920 | biostudies-literature
Project description:The scope of activity of the Blood Transfusion Service (BTS) makes it unique among the clinical laboratories. The combination of therapeutic and diagnostic roles necessitates a multi-faceted approach to utilization management in the BTS. We present our experience in utilization management in large academic medical center.
| S-EPMC4403789 | biostudies-literature
Project description:OBJECTIVES:Little is known about platelet transfusions in pediatric critical illness. We sought to describe the epidemiology, indications, and outcomes of platelet transfusions among critically ill children. DESIGN:Prospective cohort study. SETTING:Multicenter (82 PICUs), international (16 countries) from September 2016 to April 2017. PATIENTS:Children ages 3 days to 16 years prescribed a platelet transfusion in the ICU during screening days. INTERVENTIONS:None. MEASUREMENTS AND MAIN RESULTS:Over 6 weeks, 16,934 patients were eligible, and 559 received at least one platelet transfusion (prevalence, 3.3%). The indications for transfusion included prophylaxis (67%), minor bleeding (21%), and major bleeding (12%). Thirty-four percent of prophylactic platelet transfusions were prescribed when the platelet count was greater than or equal to 50 × 10 cells/L. The median (interquartile range) change in platelet count post transfusion was 48 × 10 cells/L (17-82 × 10 cells/L) for major bleeding, 42 × 10 cells/L (16-80 × 10 cells/L) for prophylactic transfusions to meet a defined threshold, 38 × 10 cells/L (17-72 × 10 cells/L) for minor bleeding, and 25 × 10 cells/L (10-47 × 10 cells/L) for prophylaxis in patients at risk of bleeding from a device. Overall ICU mortality was 25% but varied from 18% to 35% based on indication for transfusion. Upon adjusted analysis, total administered platelet dose was independently associated with increased ICU mortality (odds ratio for each additional 1 mL/kg platelets transfused, 1.002; 95% CI, 1.001-1.003; p = 0.005). CONCLUSIONS:The majority of platelet transfusions are given as prophylaxis to nonbleeding children, and significant variation in platelet thresholds exists. Studies are needed to clarify appropriate indications, with focus on prophylactic transfusions.
| S-EPMC6476545 | biostudies-literature
Project description:Human platelets play a key role in hemostasis and thrombosis and have recently emerged as key regulators of inflammation. Platelets stored for transfusion produce pro-thrombotic and pro-inflammatory mediators implicated in adverse transfusion reactions. Correspondingly, these mediators are central players in pathological conditions including cardiovascular disease, the major cause of death in diabetics. In view of this, a mass spectrometry based proteomics study was performed on platelets collected from healthy and type-2 diabetics stored for transfusion. Strikingly, our innovative and sensitive proteomic approach identified 122 proteins that were either up- or down-regulated in type-2 diabetics relative to nondiabetic controls and 117 proteins whose abundances changed during a 5-day storage period. Notably, our studies are the first to characterize the proteome of platelets from diabetics before and after storage for transfusion. These identified differences allow us to formulate new hypotheses and experimentation to improve clinical outcomes by targeting "high risk platelets" that render platelet transfusion less effective or even unsafe.
| S-EPMC3017716 | biostudies-literature
Project description:Genetically modified mice have advanced our knowledge on platelets in hemostasis and beyond tremendously. However, mouse models harbor certain limitations, including availability of platelet specific transgenic strains, and off-target effects on other cell types. Transfusion of genetically modified platelets into thrombocytopenic mice circumvents these problems. Additionally, ex vivo treatment of platelets prior to transfusion eliminates putative side effects on other cell types. Thrombocytopenia is commonly induced by administration of anti-platelet antibodies, which opsonize platelets to cause rapid clearance. However, antibodies do not differentiate between endogenous or exogenous platelets, impeding transfusion efficacy. In contrast, genetic depletion with the inducible diphtheria toxin receptor (iDTR) system induces thrombocytopenia via megakaryocyte ablation without direct effects on circulating platelets. We compared the iDTR system with antibody-based depletion methods regarding their utility in platelet transfusion experiments, outlining advantages and disadvantages of both approaches. Antibodies led to thrombocytopenia within two hours and allowed the dose-dependent adjustment of the platelet count. The iDTR model caused complete thrombocytopenia within four days, which could be sustained for up to 11 days. Neither platelet depletion approach caused platelet activation. Only the iDTR model allowed efficient platelet transfusion by keeping endogenous platelet levels low and maintaining exogenous platelet levels over longer time periods, thus providing clear advantages over antibody-based methods. Transfused platelets were fully functional in vivo, and our model allowed examination of transgenic platelets. Using donor platelets from already available genetically modified mice or ex vivo treated platelets, may decrease the necessity of platelet-specific mouse strains, diminishing off-target effects and thereby reducing animal numbers.
| S-EPMC7271594 | biostudies-literature
Project description:Introduction:In October 2015, the Food and Drug Administration (FDA) instituted an update to the mandatory Risk Evaluation and Mitigation Strategy (REMS) program for clozapine to improve safety monitoring of hematologic events. However, the impact of the clozapine REMS program on reporting of hematologic adverse events has not been quantified. Methods:We assessed adverse event reports for agranulocytosis, granulocytopenia, leukopenia, and neutropenia from the FDA Adverse Event Reporting System (FAERS) for a 1-year time period before (October 2014 to September 2015, pre-REMS) and after (October 2015 to September 2016, post-REMS) the implementation of the clozapine REMS program. The AERSMine platform was used to capture historical effect estimates (October 2004 to September 2014). Reporting odds ratios (ROR), proportional reporting ratios (PRR), and corresponding Taylor series 95% confidence intervals (CIs) were calculated for hematologic events with clozapine compared with all other medications using OpenEpi. Results:Reporting rates for agranulocytosis, granulocytopenia, leukopenia, and neutropenia with clozapine all increased from the pre-REMS to post-REMS time frames, ranging from a 2-fold increase with leukopenia to a 40-fold increase with neutropenia; the composite measure of all hematologic reports had a 12-fold increase. During the post-REMS time frame, the ROR increased by 1691% (111.4, 95% CI 100.6-123.4) compared with the pre-REMS time frame (7.1, 95% CI 5.2-9.6), and the PRR increased by 1280% (83.1, 95% CI 76.8-90.0 vs 6.9, 95% CI 5.1-9.4) for the composite outcome. Discussion:We observed significant increases in reports of hematologic adverse events with clozapine after the introduction of the clozapine REMS program. Future research should explore the impact of the less stringent exclusionary and discontinuation criteria on utilization (eg, expanded access) and clinical outcomes (eg, treatment effectiveness and adverse events).
| S-EPMC7213944 | biostudies-literature
Project description:BACKGROUND:Leukoreduction (LR) of platelet concentrate (PC) has evolved as the standard to mitigate risks of alloimmunization, clinical refractoriness, acute transfusion reactions (ATRs), and cytomegalovirus infection, but does not prevent transfusion-associated graft-versus-host disease (TA-GVHD). Amotosalen-ultraviolet A pathogen reduction (A-PR) of PC reduces risk of transfusion-transmitted infection and TA-GVHD. In vitro data indicate that A-PR effectively inactivates WBCs and infectious pathogens. STUDY DESIGN AND METHODS:A sequential cohort study evaluated A-PR without LR, gamma irradiation, and bacterial screening in hematopoietic stem cell transplant (HSCT) recipients. The first cohort received conventional PC (control) processed without LR, but with gamma irradiation and bacterial screening. The second cohort received A-PR PC (test) processed without: LR, bacterial screening, or gamma irradiation. The primary efficacy outcome was the 1-hour corrected count increment. The primary safety outcome was treatment-emergent ATR. Secondary outcomes included clinical refractoriness, and 100-day status for engraftment, TA-GVHD, HSCT-GVHD, infections, and mortality. RESULTS:Mean corrected count increment (× 103 ) of 33 test PC recipients was similar (18.9 ± 8.8 vs. 16.6 ± 8.4; p?= 0.296) to that of 31 control PC recipients. Test recipients had a reduced, but nonsignificant, incidence of ATR (test?= 9.1%, Control?=?19.4%; p?= 0.296). The frequencies of clinical refractoriness (0 of 33 vs. 4 of 31 patients) and refractory transfusions (6.6% vs. 19.3%) were lower in the test cohort (p?= 0.05 and 0.02), respectively. No patient in either cohort had TA-GVHD. Day 100 engraftment, HSCT-GVHD, mortality, and infectious disease complications were similar between cohorts. CONCLUSIONS:This study indicated that A-PR PC without LR, gamma irradiation, or bacterial screening is feasible for support of HSCT.
| S-EPMC6850058 | biostudies-literature