Vox Sanguinis最新文献

Background and objectives: The artificial intelligence (AI) field holds significant promise to revolutionize healthcare, including transfusion medicine (TM). This study explored AI use in TM, education and research among International Society of Blood Transfusion (ISBT) members.

Materials and methods: A mixed methodology was employed. A survey was conducted June to November 2024. Eighteen participants were interviewed.

Results: A total of 218 ISBT members from 67 countries responded to the survey, 43.5% of which use AI. Most users (91.1%) have used Generative AI (GenAI); 82.3% indicated they were self-taught. Application to clinical TM was reported by 54.4%, and 87.3% reported a positive impact. A third of respondents (32.7%) indicated the use of AI in their institutions, commonly GenAI tools. More than two-thirds indicated use in TM education, research or both, and 71.1% indicated a positive impact on their institution's operations. Use in education included preparing lectures and generating questions. Use in research included brainstorming ideas, statistical analysis, coding, data interpretation, manuscript drafting and proofing. Survey respondents reported various challenges in adopting AI, including lack of access to AI resources or expertise (78%), cost (74%), difficulty in hiring AI professionals (73%) and data privacy concerns (72%). Concerns raised during interviews included accuracy of information, regulatory constraints and risks on intellectual ability and employment.

Conclusion: There is general interest in the use of AI in TM practice, education and research. Barriers to adoption include access to the technology and lack of AI professionals. Educational resources must be expanded. Regulatory constraints and privacy and trust concerns need to be addressed.

Background and objectives: Alloantibodies against high-prevalence antigens can create significant barriers to transfusion, particularly in patients with complex medical needs. Serological investigations include use of enzyme-treated red cells and dithiothreitol (DTT) testing, which can enhance or diminish antibody reactivity, providing insight into potential antibody specificity. Additionally, molecular testing can predict the absence of a common antigen and identify the corresponding antibody.

Materials and methods: We describe the case of a Palestinian woman with cancer who had previously received compatible red blood cell (RBC) transfusions at Sheikh Shakhbout Medical City (SSMC) without complications. Upon readmission for a new chemotherapy cycle, pre-transfusion testing revealed a panagglutinin reactive with most reagent red cells, suggesting an alloantibody directed against a high-prevalence antigen. Enzyme-treated cells, 2-aminoethylisothiouronium bromide hydrobromide (AET) and DTT testing suggested involvement of the Kell blood group system. Molecular genotyping failed to predict antigen absence. However, the discrepancy between predicted phenotype and serologically determined phenotype at SSMC and Versiti Blood Center of Wisconsin led us to suspect an exon variant in the KEL gene.

Results: A KEL*02N.19 allele causing absence of Kell antigens was identified. The absence of reactivity with three examples of K₀ reagent red cells and with artificially created K₀K₀ cells confirmed a K₀ phenotype with anti-Ku. With no compatible RBC units available, a multidisciplinary team developed a non-transfusion-based management plan. Remarkably, the patient was able to complete her cancer treatment without requiring further transfusion.

Conclusion: This case illustrates the importance of integrating serological, enzymatic and molecular approaches in the identification of antibodies to high-prevalence antigens and highlights alternative strategies to manage transfusion in complex oncology patients.

Background and objectives: Blood services witnessed significant declines of donor returns during the COVID-19 pandemic. Should another public health crisis occur, this experience may provide important insights for the development of strategies to maximize donor return. Here, we explored how contracting a SARS-CoV-2 infection impacted interdonation interval.

Materials and methods: This was a retrospective cohort study of plasma donors who were not SARS-CoV-2-vaccinated at the time of inclusion. The study took place in Québec, Canada. Donors were included if they had donated plasma twice: once between March 1 2020 and 30 June 2020 and once more within the next 24 months. Donors with ('infected') and without ('non-infected') a self-reported SARS-CoV-2 infection were matched 1:1 based on sex, age and number of previous donations. Cox proportional hazard ratios (HRs) and 95% confidence intervals (CIs) were reported.

Results: The matched cohorts each comprised 108 donors, including 50.0% of female donors (mean age ± standard deviation [years]: infected = 40.5 ± 16.2; non-infected = 41.0 ± 16.4). Interdonation interval was significantly longer among infected donors than among non-infected donors, whether it be in the full cohort (HR [95% CI] = 0.566 [0.428-0.749]) or among female donors (HR [95% CI] = 0.429 [0.278-0.660])-but not among male donors (HR [95% CI] = 0.813 [0.527-1.254]).

Conclusion: In this study, a self-reported SARS-CoV-2 infection was associated with a significantly longer interdonation interval.

Background and objectives: The Vel antigen is clinically significant and its alloantibody is involved in haemolytic transfusion reactions. This antigen has a high prevalence in the population. The Vel-negative phenotype is the result of a homozygous deletion in the SMIM1 gene (c.64_80del) and hinders the expression of the SMIM1 protein.

Materials and methods: A total of 17,472 blood donor samples from the Center for Hematology and Hemotherapy of Santa Catarina State were genotyped targeting the 17-nucleotide (c.64_80del) deletion in the SMIM1 gene. The same method was applied to the siblings of the donors identified as Vel-negative.

Results: The frequency of the c.64_80del17 deletion was 0.90%, and 0.03% of the donors were Vel-negative. In the family study, two individuals were identified as having the homozygous c.64_80del.

Conclusion: These findings underscore the relevance of identifying Vel-negative donors for enhancing rare donor registries and improving transfusion safety.

Background and objectives: Understanding differences in blood donor vaccine uptake is essential for accurately interpreting serosurveillance of vaccine-preventable diseases and other research using donor samples and/or data. We aimed to assess vaccination uptake in donors and non-donors.

Materials and methods: We linked the Sax Institute's 45 and Up Study data to blood donation records, the Australian Immunization Register and death records. Participants were categorized as active donors, lapsed donors or non-donors. Influenza, herpes-zoster, pneumococcal and COVID-19 vaccine uptake were analysed in the age groups recommended and eligible for free vaccination and for pertussis in the age group recommended. We calculated age- and sex-adjusted uptake percentages and differences averaged across 2021-2023, except for COVID-19 vaccine. Multivariable regression models were used to assess the association between donor status and vaccination uptake, adjusting for potential confounders.

Results: Of the 266,432 participants available for this research, 216,338 were eligible for analysis in 2021. Of these, 5734 (2.7%) were active donors, 29,237 (13.5%) were lapsed donors and 181,367 (83.8%) were non-donors. Active donors had higher vaccination uptake than non-donors (adjusted uptake ratio [95% confidence interval, CI] for influenza 1.05 [1.04, 1.06], herpes-zoster 1.20 [1.13, 1.28], pneumococcal 1.10 [1.03, 1.17], pertussis 1.09 [1.00, 1.18]), ≥2 doses of COVID-19 vaccine in 2021 1.02 [1.01, 1.02] and booster COVID-19 dose in the second half of 2023 1.08 [1.02, 1.15]. Similarly, lapsed donors had higher vaccination uptake than non-donors.

Conclusion: Blood donors have a higher uptake for funded/recommended adult vaccines than non-donors. These findings provide evidence of vaccination rate differences that may impact interpretation of studies where blood donor samples and/or data are used.

Background and objectives: Haemolytic disease of the foetus and newborn (HDFN) is a potentially severe condition caused by maternal alloimmunization against foetal red blood cell (RBC) antigens. In the Netherlands, female transfusion recipients under 45 years currently receive RBCs matched for c, D, E and K antigens (D and cEK-matching) to prevent alloantibody formation. We evaluated the cost versus utility of cEK-matching strategies to optimize the prevention of HDFN.

Materials and methods: Four strategies for females under 45 years of age were compared: current cEK-matching, cK-matching, K-matching and no antigen matching. The model used recent Dutch data on alloimmunization incidence and incorporated lifetime costs and quality-adjusted life years (QALYs). Sensitivity analyses were conducted to assess robustness across different assumptions.

Results: Compared to the current cEK-matching strategy, cK-matching reduced lifetime costs by €79,000 per yearly cohort of 177,248 pregnant women, with a minor QALY loss of 0.02. Matching for K only and no matching were both associated with higher costs and greater QALY losses. Across all plausible willingness-to-pay (WTP) thresholds, cK-matching had the highest probability of being cost effective.

Conclusion: Transfusion matching for c and K, but not E, is the most cost-effective strategy to prevent HDFN in the Dutch setting. Matching for E provides minimal health benefit at higher costs. These findings support revising current guidelines to cK-matching, ensuring optimal prevention of HDFN while reducing healthcare expenditures.

Background and objectives: Foetal and neonatal alloimmune thrombocytopaenia (FNAIT) is a potentially severe immune-mediated condition that is believed to be under-identified in the Canadian population. The Canadian Blood Services National Platelet Immunology Reference Laboratory (NPIRL) serves as a centralized referral laboratory for FNAIT investigations across Canada. Diagnostic evaluation includes human platelet antigen (HPA) genotyping and maternal anti-HPA antibody testing. This study is a review of all FNAIT investigations referred to NPIRL to assess testing patterns, antibody detection rates and evidence of under identification at a national level.

Materials and methods: All maternal, paternal and neonatal samples related to FNAIT investigations between 20 January 2014 and 31 December 2024 were extracted from the NPIRL database. The geographic origin of samples, HPA genotyping and antibody specificity, if present, were documented.

Results: A total of 1986 samples (1076 maternal, 620 paternal and 290 neonatal) were received for FNAIT investigation over the 11-year study period. One-hundred and thirty-five HPA antibodies were identified in 130 of the maternal samples tested, with anti-HPA-1a and HPA-5b being the most frequently detected specificities. Despite a modest increase in annual referrals, the total number of investigations and antibody-positive cases was substantially lower than expected based on Canadian birth rates and published FNAIT incidence estimates.

Conclusion: Referral patterns and laboratory findings from NPIRL demonstrate a marked discrepancy between expected FNAIT incidence and observed diagnostic activity in Canada, indicating that FNAIT is substantially under-identified. These findings highlight the need for improved recognition, standardized investigation pathways and enhanced diagnostic strategies to reduce missed cases and improve neonatal outcomes.

Background and objectives: The European Union's ban on the use of di(2-ethylhexyl) phthalate (DEHP) in medical devices will take effect in 2030. DEHP is a plasticizer in polyvinyl chloride blood bags that helps stabilize the red blood cell membrane during hypothermic red blood cell concentrate (RBCC) storage. Recent studies have shown that RBCCs have acceptable in vitro quality after storage in DEHP-free containers (e.g., plasticized with di(2-ethylhexyl) terephthalate [DEHT] and stored in phosphate-adenine-glucose-guanosine-saline-mannitol [PAGGSM] additive solution). To complement quality data, in this study, we compared bacterial growth in RBCCs stored in either DEHT/PAGGSM or DEHP/saline-adenine-glucose-mannitol (SAGM).

Materials and methods: Paired ABO-matched whole blood units were collected into DEHT/PAGGSM sets, pooled and split into one DEHT/PAGGSM and one DEHP/SAGM bag set. RBCCs were produced using a top/bottom buffy coat process, tested for baseline in vitro quality and sterility, and spiked with Yersinia enterocolitica, Serratia liquefaciens and Listeria monocytogenes (~10² CFU/mL) and Cutibacterium acnes (~10³ CFU/mL) (N = 3). RBCCs were stored at 1-6°C for 43 days and sampled weekly for bacterial enumeration. Bacterial counts were compared between DEHP/SAGM and DEHT/PAGGSM RBCCs over 43 days of storage.

Results: For Y. enterocolitica, S. liquefaciens and C. acnes, no differences in survival/growth between DEHP/SAGM and DEHT/PAGGSM RBCCs were observed. Y. enterocolitica and S. liquefaciens grew to 10⁸-10⁹ CFU/mL by day 14, while C. acnes remained at 10³ CFU/mL until day 43. L. monocytogenes counts declined in DEHT/PAGGSM compared to DEHP/SAGM RBCC on days 0-7, but bacterial loads were similar (~10⁷ CFU/mL) in both bags by day 43.

Conclusion: These results suggest that the bacterial safety risk of RBCCs is not increased in DEHT/PAGGSM containers.

Background and objectives: Immune-mediated haemolysis caused by red blood cell (RBC) auto or alloantibodies depends on several factors, including antibody subclass. Immunoglobulin (Ig) IgG1 and IgG3 are more efficient at triggering phagocytosis and complement activation. This study evaluated whether IgG subclass determination can help predict the clinical relevance of RBC antibodies in different immunohaematological contexts.

Materials and methods: Blood donors and patients with IgG-positive direct antiglobulin tests (DATs) were included. IgG subclasses were determined using monospecific gel cards for IgG1/IgG3. The monocyte monolayer assay (MMA) assessed in vitro biological relevance. Antibody specificity was established by standard immunohaematological techniques. Statistical comparisons were performed using Chi-square, Fisher's exact and Mann-Whitney U tests.

Results: Among patients with IgG autoantibodies (n = 29), 51.7% had IgG1 or IgG3, versus 3.7% of donors (n = 27; p < 0.001). The presence of IgG1/IgG3 autoantibodies showed 93% positive predictive value (PPV) and 96.3% specificity for distinguishing patients from donors. IgG1/IgG3 autoantibodies were more frequently associated with positive MMA results (83.3% vs. 33.3%). Among RBC alloantibodies (n = 17), 64% were IgG1/IgG3, correlating with MMA positivity (sensitivity 78%; PPV 77%). Antibodies traditionally considered benign were often IgG1/IgG3 and MMA-positive.

Conclusion: IgG subclass determination provides diagnostic value beyond IgG quantification alone. In DAT-positive donors, not detecting IgG1/IgG3 is compatible with a low haemolysis risk and often obviates follow-up; when IgG1/IgG3 are detected, selective evaluation may be appropriate. For alloantibodies, subclass identification may help predict clinical relevance, especially in urgent transfusion settings when MMA is unavailable, supporting transfusion safety decisions and efficient resource use.

Background and objectives: To characterize and analyse 57 ABO subgroup samples from volunteer non-remunerated blood donors in Ningxia, China, and elucidate the distribution profile of ABO subgroups in this region.

Materials and methods: Routine ABO serological testing was performed on 568,286 blood donors from 2014 to 2024. Fifty-seven samples exhibiting forward/reverse typing discrepancies underwent full-length ABO gene sequencing using third-generation single-molecule sequencing technology.

Results: Among the 57 subgroup samples, phenotypes were distributed as follows: A2 (n = 1), Aweak (n = 10), Ax/Aweak (n = 3), Bweak (n = 10), Bel (n = 4), A2B (n = 5), AweakB (n = 3), A1Bel (n = 1), Ax/AweakB (n = 3), A1Bweak (n = 10), cisAB (n = 3), B(A) (n = 4). Third-generation sequencing identified 11 A-subgroup alleles, 10 B-subgroup alleles and 3 cisAB/BA alleles. A novel allele was discovered, ABO*A.NEW, with a novel variant c.575T>C (NCBI accession number: PV290155).

Conclusion: The frequency of ABO subgroups in Ningxia blood donors was 1 per 10,000. A-subgroups were predominantly ABO*AW.NEW (c.575T>C). B-subgroups were primarily ABO*BW.12. Complex glycosyltransferase alleles included ABO*cisAB.01, ABO*BA.02 and ABO*BA.04.