Vox Sanguinis最新文献

Background and objectives: Sickle cell trait (SCT) persons are significant donors, and discarding these blood units reduces their supplies, mainly in the third-world countries. This work focused on 12 metabolites associated with the red blood cell (RBC) storage lesion and 23 amino acids in the supernatants of packed RBC units from SCT and reference (non-SCT) donors stored in the same conditions.

Materials and methods: All samples of RBC concentrates were collected and separated from the storage of Colsan (Beneficient Association of Blood Collection), where they were routinely processed and separated as packed RBC units and stored in the refrigerator (2°-6°C). The supernatant samples of each packed RBC bag were separated by centrifugation at days 1, 7, 14, 21, 28 and 35 of storage and kept at -80°C till the metabolite analysis together.

Results: The quantitation of metabolites and amino acids examined in the supernatant of SCT and reference donors showed no statistical differences along the cold storage. Lactic acid and malic acid releases occur in three phases during RBC storage. Basic and acid amino acids and corresponding amides have low and stable values during the first 14 days of storage, followed by a steep increase.

Conclusion: Our metabolomic results give elements that seem not to contraindicate the transfusion of RBC with SCT, besides its more structural fragility.

Background and objectives: The available information on blood groups in the Chilean population is derived from studies on aboriginal cohorts and routine serological test results. The purpose of this study is to conduct a comprehensive analysis of genotypes, phenotypes and blood group alleles in donors from northern, central and southern Chile using molecular methods.

Materials and methods: Overall, 850 samples from donors in northern, central and southern Chile were genotyped. Allelic, genotypic and antigenic frequencies were calculated and compared among regions. Of these, 602 samples were analysed by haemagglutination, and discrepancies found between phenotypes and genotypes were investigated. The immunogenic potential of antigens was calculated by the Giblett equation, using the antigenic frequencies of donors from Santiago and the alloantibody frequencies of patients from the same region.

Results: Alleles of low prevalence, variant alleles and those responsible for the absence of high-prevalence antigens were found. Significant differences were observed between the antigenic frequencies of the three regions. Discrepancies between serologic and molecular results were mostly attributed to the molecular background affecting antigen expression. In the calculation of the immunogenic potential of antigens, the highest value was attributed to the Di^a antigen.

Conclusion: These findings represent the first molecular characterization of blood group antigens in Chileans. Our results highlight the necessity of using molecular tools to explore the genotypes underlying variant phenotypes, low-frequency antigens and antigens lacking specific antisera that cannot be detected by haemagglutination. Additionally, they emphasize the importance of understanding the distribution of blood groups among different populations.

Background and objectives: An extra health screening, including glycated haemoglobin (HbA1c), total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), was initiated for regular donors aged over 40 in Taiwan in November 2015. This study aimed to determine its benefits on donor health management and retention.

Materials and methods: A stratified random mail survey was conducted among donors who received HbA1c, TC and LDL-C screening between November 2015 and June 2017 to investigate their awareness of the screening, medical histories and post-screening behaviours. Their subsequent screening results and donation records from 3 years before and after the initial screening were obtained up to December 2021.

Results: In total, 2070 donors participated in the mail survey, with participation rates ranging 15.7%-23.2% across study groups. The screening newly detected hyperglycaemia in 1.6% (95% confidence interval [CI]: 1.2%-2.0%) and hyperlipidaemia in 1.0% (95% CI: 0.7%-1.4%) of participants, with 42.7% (95% CI: 40.3%-45.2%) of participants unaware of the screening. Participants with initially abnormal or borderline TC or LDL-C results showed significant decreases in the subsequent screening (all p values<0.05). No difference was found in participants' awareness of the screening. However, those who sought medical consultation or made specific lifestyle changes tended to show greater improvements. Awareness of the screening was associated with increased whole blood donations and donated units.

Conclusion: The extra health screening has limited benefits for donor health management without additional interventions, but it may motivate donors to donate more frequently. Raising donors' awareness of the screening is also crucial to maximize its benefits.

Background and objectives: Previously published studies have consistently identified significant variation in red blood cell (RBC) transfusions during cardiac surgery. Clinical guidelines can be effective at improving the average quality of care; however, their impact on variation in practice is rarely studied. Herein, we estimated how variation in RBC use across cardiac surgeons changed after the publication of national patient blood management guidelines.

Materials and methods: We performed a pre-post study estimating change in variation in RBC transfusions across 80 cardiac surgeons in 29 hospitals using a national cardiac surgery registry. Variation across surgeons was estimated using fixed-effects regressions controlling for surgery and patient characteristics and an empirical Bayes shrinkage to adjust for sampling error. RBC use was measured by three metrics-the total number of units transfused, the proportion of patients transfused and the number of units transfused, conditional on receiving RBC.

Results: The primary analysis utilized 35,761 elective cardiac surgeries performed between March 2009 and February 2015 and identified a 24.5% reduction (p < 0.0001) in mean total units transfused accompanied by a 37.2% reduction (p = 0.040) in the variation across surgeons. The reduction in mean total units was driven by both the proportion of patients transfused and the number of units transfused, conditional on receiving RBC, while the reduction in variation was only driven by the latter.

Conclusion: In our study of RBC transfusions across cardiac surgeons, the surgeons who used more RBC in the pre-guideline period experienced larger reductions in RBC use after the guidelines were published.

Background and objectives: Reproductive-aged women are at an increased risk of developing iron deficiency (ID). We aimed to develop a non-invasive screening tool to identify ID in women and assess the acceptability of screening.

Study design and methods: We screened women (age 18-49 years) in the community of Western Australia.

Primary outcome: acceptability of screening, assessed by the feasibility of recruiting the required sample size (n = 323).

Secondary outcomes: Hand grip strength, finger prick haemoglobin concentration (Hb), prevalence of heavy menstrual bleeding (HMB), diet, pregnancy history, blood donation, symptoms of ID and history of ID or anaemia (Hb < 120 g/L). Those with Hb <130 g/L and no history of iron therapy in the past 2 years were given referrals for venous full blood count and ferritin sampling.

Results: Across 5 days, we recruited 640 eligible women. Of which, 178 (28%) had HMB and 79 (12%) were anaemic. Mean age was 33.5 ± 9.2 years, and mean Hb was 132.4 ± 11.9 g/L. In the past 2 years: 335 (52%) were diagnosed with ID or anaemia; 322 (50%) had taken oral iron; and 210 (33%) had an intravenous iron infusion. Vegetarian diets were followed by 89 (14%); 40 (6%) were regular blood donors; 290 (45%) had a previous pregnancy. HMB increased the risk of symptoms of ID and having prior ID/anaemia diagnosis (67% vs. 47%) or treatment (p < 0.022). Hand grip strength showed a positive relationship with both Hb (adjusted R² = 0.012, p = 0.004) and ferritin (adjusted R² = 0.135, p = 0.005).

Conclusion: ID screening was well accepted by women in the community, with high recruitment rates over a short period. Future screening tool development may consider incorporating hand grip strength and HMB assessment.

Background and objectives: Honduras became the first lower middle-income country (LMIC) to adopt amotosalen/UVA pathogen-reduced (PR) platelet concentrates (PCs) as a national platelet safety measure in 2018. The Honduran Red Cross (HRC) produces ~70% of the national platelet supply using the platelet-rich plasma (PRP) method. Between 2015 and 2018, PCs were screened with bacterial culture and issued as individual, non-pooled PRP units with weight-based dosing and 5-day shelf-life. PR PCs were produced in six-PRP pools with a standardized dose (≥3.0 × 10¹¹), no bacterial screening and 7-day shelf-life. Gamma irradiation and leukoreduction were not used.

Materials and methods: PC production and distribution data were retrospectively analysed in two periods. Period 1 (P1) included 3 years of PRP PCs and a transition year (2015-18). Period 2 (P2) included 5 years of PR PCs (2019-23). PC doses were standardized to an equivalent adult dose for both periods. Descriptive statistics were calculated.

Results: HRC produced 10% more PC doses per year on average in P2 compared to P1. Mean annual waste at HRC declined from 23.9% in P1 to 1.1% in P2. Two urban regions consumed 96% of PC doses in P1 and 88.3% in P2. PC distributions increased in 14/18 regions.

Conclusion: Standardized dosage, PR and 7-day shelf-life increased PC availability, reduced waste, eliminated bacterial screening and avoided additional costs for arboviral testing, leukoreduction and irradiation. Access to PC transfusion remains limited in Honduras; however, the conversion to pooled PR PCs illustrates the potential to sustainably expand PC distribution in an LMIC.

Background and objectives: Accurate human leucocyte antigen (HLA) and human platelet antigen (HPA) typing is essential for establishing a blood platelet donor bank to deal with refractoriness in patients undergoing multiple platelet transfusions. Current methods, such as Sanger and next-generation sequencing, encounter difficulties in haplotyping. Herein, the aim of this study was to establish a method for HLA and HPA typing based on the long read sequencing.

Study design and methods: The HPA and HLA class I genotypes of 268 platelet donors from the Taiyuan Blood Center, China were identified using long-read sequencing on the PacBio platform. Allele frequencies for HPA systems and HLA class I genes were calculated, and genetic variability within HPA system genes was analysed.

Results: Polymorphisms were identified in 8 of the 35 HPA systems (HPA-1 to HPA-6w, HPA-15 and HPA-21w), with the frequencies of the 'b' allele at 0.0187, 0.0709, 0.4086, 0.0075, 0.0149, 0.0317, 0.4310 and 0.0019, respectively. The alleles with the highest frequencies at the HLA-A, HLA-B and HLA-C loci are HLA-A02:01, B51:01, B46:01 and C06:02, respectively. Additionally, several genetic patterns in HPA systems were identified, including the c.166-1029C>T variant, which was found exclusively in samples carrying the HPA-1b allele.

Conclusion: This study developed a targeted long-read sequencing method characterized by high throughput and simultaneity, capable of resolving allele ambiguities for effective HLA class I genotyping in establishing a platelet donor bank.

Background and objectives: Implementation of national haemovigilance programmes has significantly improved donor and recipient safety. Recently, India completed a decade of successful implementation of its national haemovigilance programmes. The national programme is still enrolling more blood centres. This study aimed to highlight the strengths and weaknesses of Haemovigilance Programme of India (HvPI), thereby providing valuable insights for future initiatives.

Materials and methods: The National Coordinating Centre (NCC) conducted a multi-centre, cross-sectional questionnaire-based survey among the reporting blood centres (January to April 2022). The survey consisted of three sections with a total of 27 questions focusing on the demographics of the participant blood centre as well as the impact on the recipient and donor haemovigilance. The survey was sent to 733 blood centres regularly reporting to the donor and recipient HvPI through Donor and Hemovigil Software.

Results: Total 296 responses were received (response rate of 40.4%) with maximum participation of private non-teaching hospital-based blood centres (33.8%). After their involvement in recipient HvPI, 85.7% of the respondents reported changes in their blood centre's work procedures, with the maximum improvement seen in the documentation of transfusion reactions (92.7%). Out of the 278 respondents who participated in donor HvPI, 89.9% (250) found that their blood centre's policies or work process changed as a result of their involvement in the programme.

Conclusion: In conclusion, our haemovigilance programme facilitates national collaboration for learning and sharing experiences, leading to improved policies and practices in reducing adverse reactions for both recipients and donors.