Vox Sanguinis最新文献

Background and objectives: According to the World Health Organization, more than 1 billion people are at risk of leishmaniasis in over 89 countries. Environmental changes such as deforestation, urban expansion and climate change facilitate the spread of sand fly vectors and reservoirs, increasing disease transmission. The introduction of Leishmania into non-endemic regions may be further driven by globalization and ecotourism. Transfusion transmission, particularly of Leishmania infantum, remains a concern due to the parasite's ability to survive under blood storage conditions and its prolonged latent phase. We aimed to determine the prevalence of Leishmania spp. among blood donors in a non-endemic region.

Materials and methods: A prospective, cross-sectional study was conducted with 5145 blood donor samples collected from January to December 2023. Serological screening was performed using an in-house immunoglobulin G (IgG) ELISA based on Leishmania chagasi antigen. Samples with positive or inconclusive ELISA results were further tested by real-time PCR targeting internal transcribed spacer (ITS) and kinetoplast DNA (kDNA) regions, according to Pirmez et al. RESULTS: Among samples tested, 2.82% (141/5145) were ELISA-reactive. None of these were positive by PCR for ITS or kDNA.

Conclusion: The absence of Leishmania DNA in ELISA-reactive samples highlights the limitations of serological screening in low-endemicity areas. Inflammatory physiological conditions, such as pregnancy and abortion, may contribute to non-specific reactivity. The incorporation of molecular methods and the adoption of universal leukoreduction are recommended measures to ensure transfusion safety and avoid unnecessary donor deferrals.

Background and objectives: Severe dry eye disease is a commonly diagnosed condition that can be treated with serum eye drops (SEDs). SEDs are manufactured from the serum obtained from whole-blood donation. Patient information provided with SEDs has not been evaluated so far. This study aims to understand patients' views on SED materials and identify possible improvements.

Materials and methods: The study period was between 1 November 2021 and 30 June 2022. Eligible patients were supplied with either autologous SED (AutoSED) or patient-tailored (allogeneic) SED (PT SED) manufactured by Australian Red Cross Lifeblood. Patients were invited to participate via email or post and completed an online survey or participated in a semi-structured telephone interview.

Results: A total of 64 patients supplied with AutoSED and 18 with PT SED completed the survey, of whom 10 and 8, respectively, were interviewed. More AutoSED (89.1%) than PT SED (58.8%) patients reported that the instructions on the carton were helpful. More AutoSED patients (78.1%) than PT SED (55.6%) reported receiving the SED brochure and that the information was easy to understand. Information on how to dispose the eye drops and the risk of treatment was easy to understand. Sixteen patients reported accessing the quick-response code to view the SED video and indicated that it was easy to understand.

Conclusion: Patient views on the materials provided with SEDs were generally positive. Suggested improvements included changing the location of sealing stickers on the carton, providing further detailed information on shelf-life after power supply challenges and natural disasters and storage and handling during travel.

Background and objectives: It remains unclear whether sleep deprivation and fasting increase the risk of vasovagal reactions (VVRs) in blood donors. This study explored this question.

Materials and methods: A large observational study was conducted in a regional blood centre handling 309,971 blood donations from 83,709 donors between 2017 and 2022. From these non-duplicated donors, 83,234 donors who donated 400 mL whole blood or apheresis blood were selected as subjects for analysis, of whom 2132 (2.6%) had VVRs. The associations of sleep duration the night before donation and the timing of the last meal before donation with VVRs were analysed together with general risk factors for VVRs, such as age, sex, body weight, donation experience and blood collection type.

Results: Younger age, female gender, lower body weight, first-time donation and apheresis donor were clear risk factors for VVRs in univariate analysis, although female gender and first-time donation were not identified as independent risk factors in multivariate analysis. There was no dose-dependent relationship between sleep duration or fasting time and VVR incidence, nor was any association identified in multivariate analysis.

Conclusion: Neither sleep duration nor donor-reported fasting time had any association with VVRs under the routine practice of providing snacks and drinks to donors just before blood donation. The present findings should help blood collection agencies to appropriately assess the risk of VVRs based on donor-reported sleep and fasting times.

Background and objectives: Screening for transfusion-transmitted infections (TTIs) among blood donors is done using qualitative screening assays. Screening values that are close to cut-off values lie in the uncertainty zone, often denoted as the grey zone (GZ). This scoping review evaluated studies that have assessed the GZ reactivity by supplementary tests and its consequences.

Materials and methods: Studies evaluating GZ or indeterminate or inconclusive results for TTI screening among blood donors were searched using PubMed, Scopus and Google Scholar databases. Full text for the included articles was reviewed and analysed for study characteristics, TTI screening and GZ reactivity. This included GZ range, repeat or confirmatory testing, follow-up of such donors, effect on donor deferral and collected blood units.

Results: A total of 16 studies were included. GZ was evaluated for human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), syphilis, Chagas disease and human T-lymphotropic virus (HTLV). GZ values ranged from 0.5 to 1.2 times sample to cut-off (S/CO) values in different studies. The protocol for repeat/confirmatory testing was also heterogeneous. During repeat testing, many donors were found to be reactive or repeat GZ reactive. In confirmatory assays, the majority were negative, but many were positive or indeterminate. The protocol for donor follow-up and deferral protocols also varied significantly among different centres.

Conclusion: GZ evaluation showed a small yet significant risk of TTI from samples identified within the GZ range. There is further need for follow-up studies to establish TTI risk from repeat reactive or indeterminate samples, which will help in establishing uniform protocols for GZ samples.

Background and objectives: Unsuccessful red blood cell (RBC) transfusion, necessitating unscheduled repeat transfusion, is common and costly. Several technologies have been developed to assess stored blood quality, but the potential cost-effectiveness of pretransfusion testing versus no testing to prevent unscheduled re-transfusion is unknown.

Materials and methods: Projected benefits and costs of implementing a hypothetical pretransfusion assay were evaluated using Markov models with 10,000 Monte Carlo simulations. Chronic RBC transfusions were modelled at 1-month intervals over a 1-year time horizon, for 'simple' and 'complicated' (requiring antigen matching) cohorts. Model inputs included transfusion costs and quality-of-life weights. Cost-effectiveness was defined as incremental net monetary benefit (INMB) > 0, assuming willingness to pay <$50,000 per quality-adjusted life year (QALY).

Results: The Centers for Medicare and Medicaid Services reimbursement for a single-unit RBC transfusion was $970 ($853-$1313) and $2377 ($2057-$3317), respectively, for the simple and complicated cohorts. The hypothetical assay was priced at $100 ($38-$163) and was assumed to lower unscheduled re-transfusions by 30%, from 64% to 45% (40%-50%). Pretransfusion testing yielded 0.02 higher QALY (95% prediction interval [PI]: 0.01-0.02); annual per-patient cost savings of $269 (95% PI: $263-$276) and $3651 (95% PI: $3633-$3669), respectively, for the simple and complicated cohorts; and INMB of $1083 (95% PI: $985-$1180) and $4347 (95% PI: $4250-$4443).

Conclusion: Assessment of RBC quality by a hypothetical test prior to transfusion may reduce the incidence and associated costs of unscheduled re-transfusions and, with modelled assumptions, could be especially cost-effective for patients with complicated chronic transfusion requirements.

Background and objectives: Allogeneic blood components and plasma-derived medicinal products (PDMPs) are cornerstone therapies in modern medicine, setting standards for quality, safety and efficacy. While platelets are traditionally transfused to prevent or control bleeding, they also serve as reservoirs of bioactive molecules with regenerative, anti-inflammatory, anti-oxidative and neuroprotective properties. This review examines how pooled human platelet lysates (HPLs) and platelet-derived extracellular vesicles (p-EVs) could be developed as therapeutic products, building on the principles established for PDMPs.

Materials and methods: We synthesize findings from preclinical and translational studies on the composition, production, mechanisms of action and clinical applications of HPLs and p-EVs, integrating insights from the PDMP industry to outline a framework for standardized development.

Results: Evidence indicates that HPLs and p-EVs from surplus or outdated platelet units show therapeutic potential in regenerative medicine, immunomodulation and drug delivery. Randomized trials in ocular graft-versus-host disease provide advanced clinical evidence, while other uses such as orthopaedics, wound healing and neurological disorders remain at exploratory or preclinical stages. Their development parallels the historical shift in plasma use, from transfusion to fractionation, offering a model for repurposing platelet concentrates (PCs). The systematic application of GMP, viral safety and regulatory frameworks can facilitate their clinical translation.

Conclusion: Platelet-derived products represent a new frontier for transfusion medicine, enabling value creation from surplus PCs. Ethical development, standardized production and stepwise clinical evaluation are essential to realize their promise in regenerative and precision medicine.

Background and objectives: Platelet-derived extracellular vesicles (PEVs) are submicron, membrane-bound particles released upon platelet activation, with a recognized role in haemostasis, inflammation and immunoregulation. PEVs remain insufficiently characterized in blood products. This study compared four isolation methods to evaluate their impact on PEV yield, purity and characteristics, aiming to identify a practical approach for transfusion service workflows.

Materials and methods: PEVs were isolated from expired single-donor aphaeresis platelet concentrates (n = 12) using methods based on different isolation principles: ultracentrifugation (UC), size exclusion chromatography (SEC), mixed size/charge separation (hybrid) and an affinity-based spin column method (affinity). Size, number and biochemical marker expression of all extracellular vesicle (EV) isolates were assessed.

Results: PEVs were successfully isolated by all methods, although at varying yields. The overall size distribution of all methods was similar, although SEC and affinity methods isolated PEVs with the largest diameters. PEV isolated by the affinity method had the lowest lipid:protein ratio, consistent with high purity. No differences in expression of EV marker CD9 or platelet activation marker CD42b were found.

Conclusion: Comparison of the physical and biochemical characteristics of the PEVs isolated by each method reveals that the affinity method was superior to other methods. In addition, its simplicity, cost effectiveness and accessibility make it a practical option for blood transfusion services to further explore the role of PEVs.

Human breast milk is the ideal source of nutrition for infants, especially for those who have premature births. However, all infants do not have access to human breast milk through their birth mothers for multiple reasons. Pasteurized donor human milk (PDHM), which is obtained from screened milk donors, is used to help nourish these babies. This is made possible by human milk banks (HMBs). Although there has been an increase in the number of HMBs globally, there is the possibility that growing demand could outpace the supply of PDHM. One way to overcome this is to use blood donation centres (BDCs) as HMB depots. There are several synergies that uniquely position BDCs to partner with or serve as depots to augment the availability of PDHM for infants in need. This may also come with certain hurdles including protocols for screening, processing and storage of milk products along with associated legal and regulatory challenges. It is imperative to establish clear guidelines regarding all these matters that could be used universally. Lastly, public awareness and education will be needed to promote and practically implement the idea of using BDCs as human milk depots. This will help eliminate any cultural or social obstacles. This article systematically examines those collaborations and the benefits, risks and challenges associated with BDCs operationally facilitating HMBs' capacity to supply PDHM.

Background and objectives: The presence of warm autoantibodies (WAAs) complicates pre-transfusion and compatibility testing. Despite attempts to provide antigen-matched red blood cells (RBCs), the risk of alloimmunization remains. Rates of alloimmunization and indications for transfusion were reviewed to streamline testing and RBC provision algorithms at a large tertiary care centre serving patients with lymphoid cancers and complex surgical needs.

Materials and methods: This retrospective observational study investigated the development of new RBC alloantibodies in patients with WAAs. This included 295,109 antibody screenings and 3129 antibody investigations (AIs) performed on 2493 patients between 1 September 2019 and 30 June 2024. AI results for patients with a history of WAAs were reviewed, along with diagnoses, transfusion data, and where applicable, phenotyping and genotyping results.

Results: Ninety-four patients had WAAs. Twenty-three of them (24%) had lymphoproliferative disorders (LPDs) and 21 (22%) required urgent antibody tests for surgical procedures. Fifty-one patients (54%) received RBC transfusions, and 30 of them (59%) had anaemia with haemoglobin below 70 g/dL. Thirteen patients (14%) required RBC genotyping because of recent transfusions or indeterminate results. The alloimmunization rate was 10%, including anti-Jk^a, anti-Kp^a, anti-Jk^b, anti-C^w, anti-Js^a and anti-Le^a, after RHDCE/K or more extended-matched RBC transfusions.

Conclusion: RBC alloantibodies develop in patients with WAAs, as the urgency of transfusions often limits the complete identification of antibodies and extended phenotype matching. With prompt investigation and RBC preparation, the risk of alloimmunization to major antibodies can be minimized.

Background and objectives: Natural disasters pose significant challenges to maintaining a continuous and safe blood supply. This study aimed to analyse the emergency response of the Turkish Red Crescent (TRC) blood services during the 2023 Turkey earthquake, focusing on blood supply continuity, donor mobilization and lessons learnt for future preparedness.

Materials and methods: A retrospective analysis was conducted using operational data from the TRC General Directorate of Blood Services. Information on blood component requests, supplies, donor mobilization, infrastructure status and personnel deployment was collected from the period immediately following the earthquake through the subsequent recovery phase.

Results: The earthquake severely disrupted blood service infrastructure in the affected provinces, resulting in the destruction of two blood collection units and damage to several facilities. Despite these challenges, the TRC successfully met demands from the transfusion centres through rapid activation of its Emergency Crisis Board, inter-regional redistribution of packed red blood cells and strategic donor management. Within 15 days, 250,708 blood units were collected nationwide-a 129% increase compared to pre-disaster levels. Controlled donation scheduling, proactive communication and inter-regional staff deployment ensured sustained operations and prevented overcollection. However, gaps in data interoperability between hospitals and TRC systems limited real-time monitoring of clinical blood usage.

Conclusion: The TRC's response demonstrated the effectiveness of a centralized and integrated blood service model in managing large-scale emergencies. Key lessons include the importance of donor flow regulation, transparent communication and improved hospital data integration to enhance future disaster preparedness and resilience.