Transfusion Medicine最新文献

Background and objectives: High-quality ABO antibody titre testing is required for ABO-incompatible haematopoietic stem cell transplantation and kidney transplantation. To assess the feasibility of automated ABO titration as an alternative to manual and semi-automatic titration during the peri-transplant period, a comparative study was conducted internally in a transfusion medicine laboratory.

Materials and methods: This study was performed in two stages. Firstly, the differences in anti-A/B detecting using conventional tube test (CTT) and manual column agglutination technology (CAT) were compared in group O pregnant women. Then, manual and automated CAT were applied to simultaneously detect ABO antibody levels in non-AB-group adult haematological oncology patients.

Results: In the first stage, four groups of 192 comparable results were generated from 48 subjects, which showed a high correlation between CTT and manual CAT (p < 0.001). However, the detection sensitivity of the latter was at least 1 fold higher dilution than that of the former. Fifty-six patients were tested in the second stage by simultaneous manual and automated CAT, and the paired titers differed within an acceptable range (±1 fold dilution). However, the concordance was slightly higher in group IgM (85.4%) than in group IgG (80.5%). Blood group specificity of ABO titers was also observed in this population, and no association between titers and other factors was found.

Conclusion: Automated CAT standardises ABO titre testing and saves labor costs, although manual review of weak positive reactions is still necessary. Due to the blood group specificity of ABO antibodies, special attention should be paid to the quality control and clinical relevance of titre testing for group O recipients in ABO-mismatched transplantation.

Iron deficiency anaemia (IDA) poses a significant health challenge during pregnancy, affecting up to 30% of pregnant women in the UK. It has been linked to poor health outcomes for the mother, foetus, and the infant. Despite its prevalence and impact, current diagnostic and therapeutic approaches are limited. Ensuring an adequate iron status in pregnancy requires prompt investigation and treatment whilst avoiding excessive iron supplementation and its associated side effects. Hepcidin, a key regulator of iron trafficking in the body, has emerged as a promising candidate for tailoring iron supplementation to individual needs and responsiveness. However, current research on hepcidin-based approaches yields mixed findings, necessitating a comprehensive review to elucidate its potential utility in guiding iron therapy for pregnant women with IDA. This literature review seeks to synthesise existing evidence to explore the role of hepcidin in personalised iron supplementation for pregnant women with IDA and to identify avenues for future research to pave the way for improved management of IDA in pregnancy.

Objectives: Trauma-induced coagulopathy (TIC) can be fatal but preventable if recognised early. With emerging uses of rotational thromboelastometry (ROTEM) to guide transfusions in trauma, patient outcomes with TIC-defined by initial ROTEM and conventional coagulation tests (CCTs) during massive haemorrhage protocol (MHP) activations were evaluated at a primary trauma centre in British Columbia.

Methods: This retrospective observational study included adult trauma patients requiring MHP from June 1, 2020, to May 31, 2022. TIC, defined by initial results including (1) ROTEM-based EXTEM A10 <40 mm, EXTEM CT >100 s, EXTEM ML30 >10%, FIBTEM A10 <10 mm; and (2) CCT-based INR ≥1.8, PTT ≥1.5 times of upper normal limit, platelets <50 x 10⁹/L, and Clauss Fibrinogen <1.5 g/L, was assessed for its correlation with mortality. Modified Poisson regression was used to model 28-day mortality.

Results: Twenty-two of sixty-eight patients (32%) had abnormal ROTEM but normal CCTs. TIC defined by CCTs was associated with increased mortality [24 h: 5/13 (38%) vs. 5/55 (9%), p = 0.025; 28d: 8/13 (62%) vs. 11/55 (20%), p = 0.002]; compared to ROTEM, which was not [24 h: 7/35 (20%) vs. 3/33 (9%), p = 0.307; 28d: 11/35 (31%) vs. 9/33 (27%), p = 0.594], despite requiring significantly higher blood component transfusion within the first 4 and 24 h of MHP (p-values<0.05).

Conclusions: ROTEM is more sensitive in identifying TIC. Patients with abnormal CCTs had a higher death rate, and those with abnormal ROTEM had no significantly increased mortality. A prospective study is required to assess the effects of ROTEM further.

Introduction: Introduction The Hy antigen is one of ten red cell antigens belonging to the Dombrock blood group system, with an antigen frequency of almost 100% in the majority of populations. Alloantibodies to high prevalence antigens cause difficulties with antibody identification and exclusion in serological investigations.

Case presentation: This review describes the management of four antenatal cases where the presence of alloanti-Hy had been identified. Hy-red blood cell units may be required for the transfusion of patients with alloanti-Hy, but currently, there are no published reports of alloanti-Hy causing haemolytic disease of the fetus and newborn (HDFN). A previous case report involving the care and management of antenatal patients with alloanti-Hy antibodies indicates a lack of evidence that alloanti-Hy causes clinical HDFN.

Results: All cases discussed in this review demonstrate a reduction in the strength of alloanti-Hy levels as pregnancy progressed. Signs or symptoms of HDFN were not observed with any of the pregnancies.

Conclusion: Factors such as antibody levels, antigenic expression, and varying clinical responses enhance our understanding of why alloanti-Hy has not been known to cause clinical HDFN. The cases presented here aim to improve understanding of alloanti-Hy in pregnancy and how to manage such cases.

Background: Extracellular vesicles (EVs) have procoagulative properties. As EVs are known to accumulate in stored blood products, we compared the EV content and coagulation capacity of leukoreduced cold-stored whole blood (CSWB) with current prehospital and in-hospital component therapies to understand the role of EVs in the haemostatic capacity of ageing CSWB.

Materials and methods: Blood was obtained from 12 O RhD-positive male donors. CSWB was compared with in-hospital component therapy of red blood cells (RBCs), OctaplasLG and buffy-coat platelets and prehospital component therapy of RBC and lyophilized plasma. Samples were drawn on Days 1 and 14 of CSWB and RBC cold storage. Blood count, haemolysis markers, rotational thromboelastometry, sonorheometry and thrombin generation were analysed. EVs were analysed using nanoparticle tracking analysis and cellular origin was determined using imaging flow cytometry.

Results: There was a trend towards increased production of both platelet and RBC-derived EVs during CSWB storage. Particle count increased during storage, whereas thrombin generation slowed down and in viscoelastic assays, clotting times prolonged, clot formation became impaired, and stiffness of the resulting clot decreased.

Conclusion: Both platelet and RBC-derived EVs increased in number in CSWB during storage. This did not appear to compensate for the in vitro decreasing haemostatic capacity of ageing CSWB, suggesting EVs produced during storage may not have active procoagulative effects, but rather reflect the ageing of blood cells.

Background: Worldwide, there has been a worrying increase in the prevalence of syphilis. Blood banks have a major role in monitoring the trend of these events, despite the bias due to the altruistic donation strategy.

Objectives: To determine the seroprevalence of syphilis and analyse its association with defined risk factors among blood donors at the regional blood center at Hospital Prof. Dr. J. P. Garrahan, period 2016-2022.

Materials and methods: Donor screening was performed with treponemal and non-treponemal tests to determine the prevalence of active and past syphilis. Sociodemographic characteristics of donors were analysed and the association with potential risk factors was assessed.

Results: A total of 72 874 donations were processed during the study period. The overall prevalence of specific anti-Treponema pallidum antibodies was 0.69% (95% CI = 0.63-0.75). Active syphilis seroprevalence was 0.30% (95% CI = 0.25-0.33). Not active syphilis seroprevalence was 0.39% (95% CI = 0.35-0.44). Anti-T. pallidum seroprevalence among first-time donations was 1.26% (95% CI = 1.14-1.38) while in repeat donations it was 0.16% (95% CI = 0.12-0.21). In univariate analysis, we found an association between syphilis and having a history of any sexually transmitted infection (OR: 5.09, 95% CI = 2.20-11.70, p < 0.01) and being first-time donors (OR: 3.48, 95% CI = 1.70-7.09, p = 0.0001).

Conclusion: Although the overall prevalence of syphilis is 0.69%, among repeat donors prevalence as low as 0.16% was found. This demonstrates the need to maintain and improve screening strategies and promotion of voluntary, altruistic and repeat donation.

Background: A large, retrospective study was designed to interrogate current NHS Blood and Transplant (NHSBT) HLA matching strategies for the provision of HLA selected platelets (HLA SP) and to determine whether additional factors such as ABO blood group matching, patient diagnosis, patient and/or donor age, sex, ethnicity, age of platelet unit at transfusion and possibly seasonal variation also play a role in transfusion efficacy.

Materials and methods: Data for 56 640 HLA SP transfusions over a 3-year period were collected. Transfusions with missing data for any factor under consideration were excluded, resulting in a cohort of 13 044 transfusions for analysis. Univariable and multivariable regression models were used to determine if any factors influenced an increase in platelet count of ≥10 × 10⁹/L. A stepwise logistic regression was applied, such that each influential factor was adjusted for effects on other factors included in the study.

Results: HLA match grade was confirmed as a significant factor in transfusion efficacy, with ABO mismatched units 20% less likely to give an adequate platelet increment (≥10 × 10⁹/L). Platelet donor age, gender and ethnicity were not significant. Conversely, patient diagnosis, ethnicity, gender and age showed significant associations with platelet increments. Some seasonal variation in efficacy of platelet transfusion was also demonstrated.

Conclusion: This study has demonstrated the efficacy of HLA SP transfusions in refractory patients with a wide range of diagnoses, the importance of HLA match grade, plus the marginal effect of ABO matching. A wide range of donor-related factors was excluded, while a number of patient-related factors were identified, requiring more extensive investigation in ongoing and independent studies, with implications for donor registry, clinical and laboratory practices.

Introduction: The quality of packed red blood cells (PRBC) is influenced by various factors such as the collection and processing method, storage conditions, type of bag materials used, anticoagulant properties, and donor characteristics. Studies have indicated that haemolysis in stored RBC bags is linked to male sex, older age, high haemoglobin count, and increased body mass index (BMI). The study's primary objective was to investigate whether a high BMI, as per Asian Pacific criteria among donors, is associated with an elevated haemolysis rate in stored RBC. Additionally, the study aimed to examine any protective effects of different types of preservatives added to blood bags against RBC haemolysis during storage.

Methods: Stored RBCs from 100 blood donors with different BMI are analysed for haemolysis on 0, 21, and last day (35/42 days) of storage. A BMI cut-off of 23 was taken for healthy and overweight consideration in blood donors. The blood bags selected for storage were either with additive solution (SAGM) or without additive along with an anticoagulant. The association of the percentage of haemolysis with different variables like age, BMI, and Haemoglobin of the donor were analysed. The correlation between the haematocrit of the bag and haemolysis was determined.

Results: This study did not find any significant increase in the percentage of haemolysis in blood bags with higher BMI on the last day of storage (p = 0.424). The haemolysis percentage was higher in bags without SAGM than in bags with an additive solution (p = 0.000). The high haematocrit of the bag has a significant positive correlation with the percentage of haemolysis (p = 0.002). Significantly higher haemolysis in CPDA-1 bags of donor RBC units of BMI >23 groups was observed (p = 0.000) compared to those stored in CPD-SAGM bags.

Conclusion: Indian population for higher BMI, as per Asia Pacific cut-off criteria, did not significantly impact the haemolysis of blood bags. Stored RBCs with SAGM, especially of donors having BMI > 23, had a protective effect against haemolysis in blood bags. The percentage of haemolysis was positively correlated with the haematocrit of stored RBC in bags.

Background and objectives: Arboviruses outbreaks are increasing in their frequency, geographical area and extension. Brazil is one of the most affected countries in the world, due to its tropical weather and favourable mosquito proliferation conditions. During outbreaks, the safety of the blood supply is a concern, in spite of the low number of transfusion-transmitted cases with clinical impact. The aim of this study was to evaluate the use of NAT for Dengue, Zika and Chikungunya RNA in actual screening.

Materials and methods: Blood donors from services located in 4 Brazilian regions were invited to participate in the study and provide an extra blood sample during the collection period between February 7, 2020, and April 4, 2020. Plasma from 21 341 donations was tested in mini pools of 6 by a duplex NAT for Dengue and Chikungunya, in addition to a Zika single assay. Confirmed viremic samples were submitted to an alternative NAT and serological assays.

Results: There were 33 (0.15%) Dengue RNA+ and 5 (0.02%) Chikungunya RNA+ donations. The South region showed the highest prevalence of Dengue-infected donors (0.29%). These results are in line with the incidence of these arboviruses on the respective geographical regions. Viremic units were discarded and blood services notified.

Conclusion: Screening blood donors for arboviruses during the outbreak season in Brazil reveals a significant number of viremic individuals. Arbovirus NAT testing is feasible and may be incorporated to the current screening policy.

Background and objective: Despite the Malawi Blood Transfusion Service (MBTS) increasing the amount of blood collected since its inception in 2004, Malawi remains with a 27% deficit in required blood supplies nationally. We sought to understand the facilitators and barriers to blood donation among secondary school students in Malawi.

Methods: We utilised a qualitative exploratory design, with a sample of 135 participants purposefully selected from 16 secondary schools across Malawi. Data collection methods included in-depth interviews with 20 participants (inclusive of first-time and repeat donors, lapsed and non-donors), 20 key informant interviews (including community leaders, policy-level stakeholders and MBTS staff), and 16 focus group discussions involving 95 participants (community stakeholders and all donor categories). We used the consolidated framework for implementation research (CFIR) to assess barriers and facilitators of blood donation, focusing only on four CFIR domains: internal and external factors; the implementation process and individual characteristics influencing blood donation.

Results: Blood donation among students are facilitated by altruism, incentives including milestone awards, knowledge, motivation, transport, peer pressure and individual health status. Common barriers cited included: negative experiences with the blood donation process, fear, unsupported environment, poor incentives, privacy issues and the donation activities starting late than scheduled.

Conclusion: While there have been efforts to motivate students to donate blood, significant barriers to blood donation still exist. Intensifying education and awareness campaigns may help dispel misconceptions and fears surrounding donation experiences and blood usage. Also, continuing with the provision of appropriate incentives including milestone awards may also encourage students.