Transfusion Medicine最新文献

Background: ABO antibodies can activate complement and cause hemolysis, sometimes with ABO minor incompatible platelet or plasma transfusions. Donor low titres of anti-ABO are used to assess transfusion safety. However, the correlation between antibody titres (measured semi-quantitatively or quantitatively) and their ability to activate complement is unclear.

Objectives: This study aimed to correlate ABO antibody (IgM/IgG) titres and the presence of IgG1/IgG3 subclasses with complement-mediated haemolysis using the CHUHE-P assay (Complement Hemolysis Using Human Erythrocytes).

Methods: Single-center blood group O donor samples were tested with semi-quantitative methods and classified in group 1 as low ABO titres if titre <100 and into group 2 as high ABO titre if titre >100. Testing included IgM/IgG antibody titration, the CHUHE-P assay, haemolysin test, and determination of IgG1/IgG3 subclasses.

Results: Group 1 had 21 and Group 2 had 56 blood donors. In Group 2, CHUHE-P positivity was not associated with IgM or IgG anti-A/B titres or haemolysin test results. IgG1 and IgG3 subclasses of anti-A were significantly associated with positive CHUHE-P. Significant differences between groups included CHUHE-P positivity (p < 0.001), IgG titres (p < 0.01) for anti-A, and CHUHE-P positivity (p < 0.001), IgM titres (p = 0.04), and haemolysin test (p = 0.02) for anti-B. In Group 1, 33% of anti-A and 23.8% of anti-B had positive CHUHE-P.

Conclusions: This study aimed to compare the ability of anti-ABO antibodies to cause complement-mediated hemolysis measured by the CHUHE-P test and the results of semi-quantitative/quantitative titration assays, the presence of IgG1 and/or IgG3, and hemolysin test results, where we highlighted an inconsistent association between the methods; the positivity for CHUHE-P was associated with the subclasses of antibodies IgG1 and IgG3.

Objectives: The objective of the current study is to determine the clinical significance of a warm autoantibody detected in patients during pregnancy.

Background: There are few published studies concerning the clinical significance of warm autoantibodies during pregnancy. The risk to the fetus is determined by the IgG autoantibody's ability to cross the placental barrier.

Materials and methods: Existing data of all obstetric patients who had a positive antibody screen with a warm autoantibody diagnosis during their pregnancy in the last 7 years from August 2016 to October 2023 were reviewed. If positive, a direct antiglobulin test (DAT) and an eluate were performed. Statistical analysis was performed to determine the clinical significance of warm autoantibody in pregnant patients. Data collected included blood type, race, age, BMI, the most recent hemoglobin before delivery, and gestation in weeks.

Results: Between August 2016 and October 2023, 23 510 pregnant patients had blood type and antibody screen completed at our institution. A total of 812 (3.5%) patients had a positive antibody screen. Only 16 (<2.0%) patients had a positive DAT and eluate confirmation of a warm autoantibody. None of the 16 patients had a previous history of warm autoantibody. 14/16 mothers did not experience an AIHA or HDFN in the newborns.

Conclusion: Pregnancy-induced warm autoantibody appears to be harmless for most mothers and their babies. The detection of a warm autoantibody in pregnancy may reflect a potential risk for both the mother and the child; however, on follow up, there were no clinical complications associated with warm autoantibodies in our patient cohort.

Background: The paucity of data pertaining to the implementation of the patient blood management (PBM) programme for platelet transfusion for improved patient outcomes with minimal risks motivated this study. The study aimed to implement an effective PBM programme for platelet transfusion therapy among haemato-oncology patients evaluating transfusion appropriateness and educational intervention for dedicated platelet transfusion practitioners (PtP).

Study designs and methods: A quasi-experimental study was conducted for 1 year after Institutional ethics committee (IEC) (as shown in Annexure I) which included pre-intervention, intervention and post-intervention phases for four months each. The study involved platelet auditing, online survey questionnaires, educational intervention for the platelet transfusion practitioners (PtP) and feedback for user satisfaction.

Results: The platelet audit showed statistically significant improvement (chi-square test, p < 0.05) in transfusion appropriateness, completeness of the forms filled, number of single donor apheresis procedures, ABO compatible transfusions and thereby reduction in platelet refractory cases during the post-intervention phase compared to the pre-intervention. The online survey showed improvement in self perceived knowledge and practice for all the stakeholders during the post-intervention period.

Conclusion: The introduction of platelet transfusion practitioners and the educational sessions they underwent, had a significant impact in achieving transfusion appropriateness for platelet therapy and they gained the ability to prioritise medical emergencies, optimise platelet inventory management and minimise wastage. Educational interventions have enhanced practitioners knowledge and sensitised them to adhere to standard evidence-based platelet transfusion guidelines.

Introduction: Implementation of transfusion guidelines might be poor due to a lack of awareness and strong practice habits. The study aimed to evaluate the impact of a new guideline-based, locally adjusted transfusion procedure on physicians' ordering patterns in a large academic medical centre.

Materials and methods: The study was a single-centre, retrospective study, analyzing period between January 2022 and December 2023. The study period was divided into three phases according to the procedure introduction: pre-introduction (January 2022-June 2022), introduction (July 2022-December 2022) and post-introduction (January 2023-December 2023, subdivided into 6-month periods). The new procedure was aimed at adult non-bleeding patients. Data on red blood cell (RBC) transfusions were obtained from a blood bank inventory and electronic health records. The appropriateness of transfusions was assessed against the newly introduced RBC procedure.

Results: During the study period, 2413 out of 3686 (65.5%) RBCs were transfused for the indication of "anaemia". The number of transfused RBCs between 2022 and 2023 decreased by 467 (32.4%) units. The appropriateness of RBC transfusions increased from 53.6% in the pre-introduction phase to 79.1% by the end of the post-introduction phase. There was a decrease in median pre- and post-transfusion haemoglobin (Hb) concentration, from 73 (IQR 66-78) and 91 (IQR 80-99) to 67 (IQR 60-73) and 84 (IQR 75-93) g L^-1, respectively. The post-introduction phase showed sustained improvement in the appropriateness of RBC transfusions.

Conclusions: The newly implemented RBC transfusion procedure, based on haemoglobin concentration and anaemia symptoms, supported by specific transfusion indications integrated into the computerised physician order entry system, resulted in a significant decrease in transfusions and an increase in appropriate transfusions. This improvement was sustained in the long term.

Background: Annually millions of platelet concentrate (PC) are transfused worldwide. The decision regarding PC transfusion is often complex; therefore, the implementation of a hospital programme designed to streamline and facilitate the decision-making process is beneficial. Such a programme helps standardise transfusion practices, ensures that PCs are used appropriately, while also optimising patient outcomes.

Objectives: The study aimed to analyse the impact of a new hospital utilisation improvement programme on PC transfusions.

Methods/materials: We performed a retrospective analysis of all PC transfusions in adult patients hospitalised in our large academic medical centre. The analysed time covered 12-month periods before and after the introduction of the program, which was based on the most recent clinical practice guidelines from the Association for the Advancement of Blood and Biotherapies. Indications for PC transfusion were divided into prophylactic and therapeutic. The new program was made available on the hospital intranet, obligatory e-learning was required from all clinical and laboratory personnel, and a computerised physician order entry was modified.

Results: The transfusion rate in the whole analysed period was 0.17%. The median pre-transfusion platelet count before and after implementation of the programme was 28 (IQR 15.0-50.0) and 24 (IQR 12.0-42.0) × 10⁹/L, respectively. Percentage of therapeutic transfusions increased from 46.7% to 57.7%. Overall the appropriateness of transfusions went up from 48.4% to 59.9%, and was higher for therapeutic (70.2% vs. 60.0%) than prophylactic (45.8% vs. 38.3%) transfusions.

Conclusion: Simple hospital utilisation improvement programme, adjusted to the local population and backed by e-learning and modification of a computerised physician order entry, can lead to a more restrictive use of PC transfusions in patients with thrombocytopenia.

Background: Individuals with Bombay and para-Bombay red blood cell (RBC) phenotypes produce anti-H antibodies associated with acute haemolytic transfusion reactions. The rarity of compatible donor units creates unique logistical challenges, especially during pregnancy as the onset of labour and fetal distress can occur without warning.

Case report: A 24-year-old female at 38 weeks gestation presented with breech fetal position and reported anti-H antibodies. Critically, the in-house antibody screen was negative by automated solid-phase red cell adherence (SPRCA), while manual testing subsequently demonstrated anti-H antibodies. Forward typing with Ulex europaeus lectin confirmed the absence of H-antigen on RBCs, while Lewis phenotyping and saliva neutralisation revealed H-antigen in secretions, consistent with the para-Bombay phenotype. Three frozen Bombay RBC units were obtained from a nationwide search, and four cross-match compatible non-Bombay (O-positive) units were also prepared. An external cephalic version (ECV) was originally planned since vaginal delivery carries lower bleeding risk than caesarean section (CS). However, acknowledging the unpredictability of ECV, the challenge of timing thawed units, and the possibilities of massive haemorrhage versus wasting rare donor blood, an elective CS was ultimately preferred. Delivery was uneventful without transfusion needs.

Conclusion: This case highlights key considerations regarding serologic identification, blood product management, and interdisciplinary clinical decision-making for patients with Bombay and para-Bombay phenotypes. First, automated SPRCA testing may provide false negative results for anti-H antibodies. Second, backup transfusion strategies for para-Bombay patients may include non-Bombay RBCs. Finally, the procurement, preparation, and use of rare blood products requires thoughtful deliberation between multiple care providers.

Objectives: To explore the serological characteristics and molecular mechanisms of an individual with the p phenotype in the Chinese population by analysing the serological and genetic background.

Background: The p phenotype, which lacks all antigens in the P1PK blood group system, is extremely rare in the Chinese population. Individuals with the p phenotype typically produce anti-PP1P^k antibodies. The P1, P^k antigens belong to the P1PK blood group system, while the P antigen is part of the GLOB blood group system. The antigens in the P1PK system are synthesised by α1,4-galactosyltransferase (α4Gal-T), while the antigens in the GLOB system are produced by 3-𝛽-N-acetylgalactosaminyl-transferase (β3GalNAc-T1). These glycosyltransferases are encoded by the A4GALT and B3GALNT1 genes.

Materials and methods: Serological techniques were employed to determine the blood types and antibodies of an individual with the p phenotype. Additionally, first- and third-generation sequencing methods were used to analyse the A4GALT and B3GALNT1 genes in the sample.

Results: The serum from the tested individual showed positive reactions with all red blood cells (RBCs) from two sets of panel RBC reagents, while it reacted negatively with a confirmed p phenotype red blood cell. The antibodies in the serum exhibited IgM + IgG properties, with IgG being the predominant type. The antibody titers at room temperature, 37°C, and 4°C were 128, 64, and 256, respectively. Sequencing analysis revealed a homozygous mutation in the A4GALT gene at rs5751348: G > T; c.343A > T; c.903C > G, while no mutation was detected in the B3GALNT1 gene.

Conclusions: The tested individual exhibited the p phenotype and likely produces anti-PP1P^k antibodies. The allele carrying rs5751348: G > T; c.343A > T; c.903C > G in the A4GALT gene has been provisionally designated A4GALT*02 N.28 (pending official recognition by ISBT).

Background: The bedside compatibility test (BCT) is the final barrier to transfusion safety, aiming to prevent ABO-incompatible incidents. This study evaluated the knowledge and practices of BCT and assessed the impact of a training session introducing a new technique of BCT based on Serafol ABO card.

Methods: This is an observational study targeting transfusion-qualified staff working at the MTM hospital in Nabeul. It involved an initial knowledge assessment, a training session on BCT principles, and post-assessment using an anonymous questionnaire that included the interpretation of Serafol ABO card examples.

Results: Among 93 participants, 18% frequently performed transfusions, and 31% had prior training. Incorrect BCT practices, including unsafe serum methods, were noted in 46%. Only 7.5% completed necessary pre-transfusion checks. The frequency of overall scores (≥50/100) increased significantly from 43% to 90% (p = 0.000) after the training session. Correct interpretation of the Serafol ABO card was achieved by 86% and 81% of participants in isogroup and non-isogroup compatible situations, respectively. However, 20.5% of participants would have transfused an incompatible unit. A significant difference was observed between doctors and paramedics in interpreting non-isogroup compatible and incompatible situations (p = 0.03). The overall mean interpretation score was 7.7/9, with a 77% compatibility accuracy rate. Professional profile parameters did not significantly influence correct responses.

Conclusion: This study revealed gaps in BCT practices, significantly improved through training and the introduction of the Serafol ABO card. Continuous training, medical assessments, and procedure monitoring are vital to enhance transfusion safety.

Background: The handling of donors with a marginally low haemoglobin is difficult and problematic and various methodologies have been applied to address this issue.

Aims: The aim of this study was to assess whether measurement of serum ferritin and subsequent management of donors with a marginally low haemoglobin had any impact on the number of subsequent donations.

Materials and methods: Such donors were prospectively randomised into an intervention group whereby their serum ferritin was measured and those in the control group where routine assessments were done as per current SOPs. In the intervention group, action was taken depending on how low the serum ferritin was. The comparator in both study arms was the number of donations that were given during the follow-up period of 3 years.

Results: We could not find any significant consequence due to this intervention.

Discussion and conclusion: The potential reasons are discussed, and we are proposing further studies on subsets of donors who are more prone to iron deficiency.