Vox Sanguinis最新文献

Background and objectives: Pathogen reduction (PR) using amotosalen-UVA was implemented for 100% of platelet concentrates (PCs) in France in November 2017. No bacterial testing was in place earlier. The impact of PR on the risk of transfusion-transmitted infections (TTIs) from November 2017 to December 2022 (vs. January 2013 to October 2017) has been published previously. To further assess the impact of PR implementation, the evaluation period was expanded to December 2024.

Materials and methods: PC-associated TTIs occurring in 2023 and 2024 were analysed and included in the assessment.

Results: Two cases of PC-associated transfusion-transmitted bacterial infections (TTBIs) were reported. The first involved Bacillus mobilis in a split pooled whole blood-derived PC. This Grade 2 TTBI was diagnosed following identification of the same pathogen in the second PC unit, quarantined for failed swirling test. The second involved Staphylococcus ureilyticus in an apheresis PC transfused to a patient who subsequently died. TTBI frequency decreased from 1/97,098 PC (n = 15 over 5 years, 2 deaths) to 1/787,662 PC (n = 3, over 7 years, 1 death) after PR implementation (p < 0.001). No human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), human T-cell lymphotropic virus (HTLV) or arboviruses TTI were reported from 2013 to 2024. No further cases of PC-associated hepatitis E virus (HEV) TTI were reported, concomitantly to HEV-nucleic acid testing implementation. A PC-associated parvovirus B19 TTI occurred in 2024. The use of PR PCs facilitated PC supply during arboviral outbreaks.

Conclusion: The reduction in PC-related TTBIs following PR implementation is confirmed. However, the recent occurrence of two severe TTBI cases highlights a persistent risk. Prevention of PR-PC-associated TTIs by non-enveloped viruses requires specific screening.

Background and objectives: Accurate detection of transfusion-transmissible infections, such as human immunodeficiency virus (HIV) and hepatitis C and B viruses (HCV/HBV), is critical to ensure blood safety, and screening assays must demonstrate high specificity and sensitivity. In this study, we compared the performances of Elecsys® HIV Duo, HCV Duo, Anti-HCV II and HBsAg II immunoassays with those of comparator assays HIV Ag/Ab Combo, Anti-HCV II and HBsAg on the Alinity® s platform and HIV Ag/Ab Combo, Anti-HCV and HBsAg Qualitative II on the Alinity i platform.

Materials and methods: Approximately 2050 plasma samples from first-time blood donors and commercial seroconversion panels were used. Specificity was assessed as the proportion of true non-reactive samples identified by each assay. Seroconversion sensitivity was evaluated based on the detection time and average interval from nucleic acid testing (NAT)-positivity to assay reactivity.

Results: Overall, all Elecsys assays evaluated had similar specificities as the corresponding Alinity s/i assays, although the absolute difference in specificity between Alinity i Anti-HCV assay and the other HCV assays was statistically significant. The seroconversion sensitivities of Elecsys HIV Duo and HBsAg II assays were similar to the corresponding Alinity s/i assays. For HCV, Elecsys HCV Duo assay detected infection earlier than Alinity s/i assays for most panels (87.0% and 91.8%, respectively), with an average detection time from NAT positivity for HCV RNA of 1.5 days versus 21.4 and 23.8 days, respectively.

Conclusion: The robust specificities and early detection capabilities of the evaluated Elecsys assays support their routine use in blood donor screening and diagnosis.

Background and objectives: Platelet antibody screening and identification are crucial and challenging. MacKay Memorial Hospital has been dedicated to this for nearly four decades. We reviewed our experience with platelet antibody detection methods and prevalence, and presented a possible case of post-transfusion purpura caused by anti-CD36.

Materials and methods: We analyzed platelet antibody screening results from 1988 to 2024. We used solid phase red cell adherence test (SPRCA) from 1988 to 2018 (9268 samples), and parallel SPRCA/enzyme-linked immunosorbent assay (ELISA) from 2019 to 2024 (2037 samples). Positive results are further identified through flow cytometry, monoclonal antibody immobilization of platelet antigens (MAIPA), or in-house platelet antigen panels. We also studied a possible case of post-transfusion purpura (PTP) caused by anti-CD36. A 79-year-old woman was treated with numerous platelet transfusions that were ineffective, with generalized purpura appearing a few days later following massive transfusion.

Results: From 1988-2018, 2800 of 9268 samples (30.2%) were positive. Six cases of neonatal alloimmune thrombocytopenia (NAITP) were identified (two anti-HPA-3a, two anti-HPA-5a, and two anti-CD36). From 2019-2024, 778 of 2037 samples (38.19%) were positive. Specific antibodies were identified in eight cases, and six of them were anti-CD36. Introduction of ELISA resulted in a 15-fold detection rate of anti-CD36 (0.02% to 0.29%), suggesting previous underestimation. In the possible PTP case, massive transfusion was started on Day 8 of hospitalization, purpura appeared on Day 15, anti-CD36 was identified on Day 21, and CD36-negative platelet transfusion was initiated on the following day. However, the patient eventually died of multiorgan failure on Day 29.

Conclusion: The prevalence of anti-CD36 antibody in the Taiwanese population was previously underestimated. Clinicians should be aware that not only human platelet antigen (HPA) but CD36 should also be considered when platelet refractoriness persists despite HLA-matched transfusion, as anti-CD36 may cause serious complications.

Background and objectives: Cytomegalovirus (CMV) causes harm in at-risk populations. Selection of seronegative donors has been used to prevent transmission. Leucodepletion reduces the potential for CMV transmission; however, the residual risk is uncertain, leading to variability in practice. This study systematically reviews the risk of CMV transmission in leucodepleted blood products compared to seronegative blood products.

Materials and methods: A systematic review identified comparative studies of CMV infection rates following transfusion of leucodepleted blood from CMV-negative or unselected donors. Preclinical studies on blood product CMV transmission, reported cases and studies that informed population risk were also reviewed. Meta-analysis was performed on comparative studies.

Results: There was no difference in the rate of infection following transfusion of leucodepleted cellular products with or without donor CMV seronegativity selection, with a relative risk of 1.21 (95% confidence interval [CI]: 0.42-3.49). No confirmed cases of CMV transmission were found. Preclinical studies showed a significant reduction in transmissible virus with leucodepletion, although no threshold could be defined. Cell-free CMV is not removed by filtration, and although it may remain a potential source of infection, there was no evidence of transmission through plasma, possibly due to detectable virus not reflecting intact transmissible virus.

Conclusion: Selecting CMV-seronegative donors did not reduce the risk of transmission when transfusing leucodepleted blood products because of the high efficiency of filters in removing transmissible cellular virus. This finding suggests CMV donor negative selection does not substantially contribute to donor safety.

Background and objectives: China faces a tight balance between clinical blood supply and demand. Vasovagal reactions (VVRs) hinder donor recruitment and retention. This study aimed to develop and validate a predictive model for the early identification of high-risk donors to guide targeted interventions.

Materials and methods: This unmatched case-control study enrolled whole-blood donors from a blood station in Xinjiang, China. VVR was defined according to the International Society of Blood Transfusion (ISBT) criteria for donation-related complications. Significant predictors identified by multivariable logistic regression were used to develop a prediction model. Model performance and calibration were evaluated using receiver operating characteristic (ROC) analysis and the Hosmer-Lemeshow (H-L) test.

Results: A total of 319 donors experienced VVRs, and 1276 served as controls. The final prediction model incorporated nine significant predictors, categorized as follows-demographic factors: age, pulse, systolic blood pressure (SBP) and body mass index (BMI); psychological factors: perceived stress level; and behavioural factors: number of donations, regular exercise, postprandial interval (≥4 h) and average sleep duration. The model demonstrated good discrimination, with areas under the ROC curve of 0.830 and 0.827 in the modelling and validation sets, respectively. Good calibration was indicated by H-L test results (modelling set: χ² = 13.817, p = 0.129; validation set: χ² = 8.698, p = 0.466).

Conclusion: The constructed prediction model is effective, providing a reference for blood station staff to assess the risk of VVRs in whole-blood donors and implement early interventions.

Blood transfusion is life-saving for patients in emergencies, but low- and middle-income countries (LMICs) often face a severe shortage of banked blood. Establishing blood banks in rural areas presents substantial logistical and economic challenges for many LMICs. Furthermore, difficult terrain, inadequate transportation infrastructure and adverse environmental conditions frequently cause delays in delivering essential blood supplies to patients in need. However, the freight transport system is undergoing a significant transformation with the introduction of unmanned aerial vehicles (UAVs), commonly known as drones. This environmentally conscious technology has made remarkable progress in recent times and demonstrates the potential to transport vital medical supplies, including blood and blood components, to remote areas during emergencies. Moreover, the use of artificial intelligence in drones has enhanced their flight safety. In this brief review, we first outline the various types of UAVs available for use, along with their respective configurations and regulatory requirements. Then we point out key problems of transfusion services within resource-limited regions, which include not having a national blood policy, a mismatch between supply and demand, a lack of robust testing facilities for bloodborne infections and not adhering to the transfusion guidelines. While resolving all challenges may seem unrealistic, we try to explore potential pathways to significantly improve blood accessibility for patients in LMICs through the strategic implementation of UAVs, considering the various barriers and facilitators associated with this innovative approach.

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.