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Background: Australian Red Cross Lifeblood (Lifeblood) performs human erythrocyte antigen (HEA) genotyping for a subset of repeat whole-blood donors through preferential selection which aims to maximise variation of results and possibility of identifying donors lacking high frequency red cell antigens., Materials and Methods: The HEA Molecular Bead chip™ assay is used by Lifeblood for donor genotyping. A review of all donor HEA genotype data from March 2019 to May 2022 (3 years) was conducted., Results: HEA genotyping was performed for 20,185donors. Due to selective genotyping of donors, a higher frequency of R1R1 predicted phenotype was identified. However, frequencies of other red cell phenotypes were relatively similar to previous reported in the Australian population. A small number of donors with rare red cell phenotypes was identified., Conclusion: Genotyping of blood donors provides an available pool of extended matched red blood cell products for matching to recipients. Additionally genotyping can improve the identification of donors with rare phenotypes. Whilst limitations exist, genotyping may reduce the need for labour intensive serotyping, improve blood inventory management, and may be useful in donor recruitment and retention., (© 2024 Australian Red Cross Lifeblood. Transfusion Medicine published by John Wiley & Sons Ltd on behalf of British Blood Transfusion Society.)

Background: Refractory patients need to be provided with HLA-matched platelets (PLTs), which require time-consuming cross-matching. Treatment of PLTs with citric acid leads to denaturation of the HLA Class I complexes without significant damage to the PLTs. HLA Class I depleted PLTs could alternatively be used to HLA-matched PLTs for transfusion. These PLTs have verified normal function up to 4-6 h after acid treatment., Materials and Methods: Buffy coat (BC) PLT concentrates were depleted of HLA Class I complexes by incubation in citric acid. The days after acid-treatment, surface expression of HLA Class I complexes, CD62P and CD63 were determined by flow cytometry, in addition to viability and mitochondrial membrane potential (MMP). Thromboelastography (TEG) tested PLT functionality., Results: Expression of HLA Class I complexes was reduced by 70%-75% in acid-treated PLTs compared to untreated PLTs from day 1 through day 7. Controls and acid-treated PLTs showed insignificant loss of MMP stored for 4 days. Analysis of the residual PLT activation and viability showed no significant differences for 4 days of storage. However, the residual PLT activation potential and viability were significantly decreased in acid-treated PLTs and control PLTs after 7 days of storage. Acid treatment caused a significant decrease in the TEG variable, reaction time (R time), for acid-treated PLTs as compared to control PLTs from days 1 through day 3., Conclusion: Our data suggest that extended storage of acid-treated PLTs is possible and will improve flexibility when planning for transfusion of patients with alloimmune PLT refractoriness caused by anti-HLA-antibodies., (© 2023 The Authors. Transfusion Medicine published by John Wiley & Sons Ltd on behalf of British Blood Transfusion Society.)

Background and Objectives: Current genotyping techniques allow typing of all relevant red cell, human leukocyte and platelet antigens in a single analysis. Even genetic markers related to donor health can be added. Implementation of this technology will affect various stakeholders within the transfusion chain. This study aims to systematically map the anticipated advantages and disadvantages of a national rollout of blood group genotyping of donors, which will affect the availability of rare donors and the implementation of an extensively typed blood transfusion policy., Materials and Methods: Two focus-group sessions were held with a wide representation of stakeholders, including representatives of donor and patient organisations. A dedicated software tool was used to collect the reflections of participants on genotyping for blood group antigens and extensive matching. Additionally, stakeholders and experts discussed various prepared propositions. All information collected was categorised., Results: From 162 statements collected, 59 statements (36%) were labelled as 'hopes' and 77 (48%) as 'fears'. Twenty-six (16%) statements remained unlabelled. The statements were divided in 18 categories under seven main themes: patient health, genotyping, privacy issues and ethical aspects, donor management, inventory management and logistics, hospital and transfusion laboratory and general aspects. The discussion on the propositions was analysed and summarised., Conclusion: Stakeholders believe that a genotyped donor pool can result in a reduction of alloimmunization and higher availability of typed blood products. There are concerns regarding logistics, costs, consent for extended typing, data sharing, privacy issues and donor management. These concerns need to be carefully addressed before further implementation., (© 2022 British Blood Transfusion Society.)

Background: Transfusion of ABO blood group-mismatched blood or administration to the wrong recipient may result in fatal adverse events. To prevent these types of errors, various strategies have been employed. Recently, we developed a novel sample collection workflow for the pre-transfusion crossmatching test and patient recognition. This study aimed to analyse the usage of the new workflow and improvements in outcomes., Methods: We analysed the number of crossmatching and wrong-patient errors among the blood transfusion cases during 3 years of data collection (from August 2018 to July 2021). From May 2021 to July 2021, the new workflow was implemented. Outcomes were calculated according to the department type, patient age and processing time. The sample processing time was defined as the time from placing the order to lab arrival., Results: The new workflow utilisation increased from 50.7% to 80.3% and wrong-patient errors decreased annually. The new workflow was used for more adults (3001/3680 samples, 81.5%) than paediatric cases (345/522 samples, 65.5%; p < 0.001) and in general wards than in the emergency room or intensive care unit. The sample processing time differed according to ward type and timing of the request (day: 28.80, 2.43-3889.43 min, night: 3.36, 2.72-1671.47 min; p < 0.001)., Conclusion: Wrong-patient errors were reduced without increasing sample-processing time after introducing the new workflow which included using an electronic identification system. The time needed for the blood processing differed according to the ward type, patient age, and timing of the request. Patient safety can be promoted by managing these factors and using an electronic identification system., (© 2022 British Blood Transfusion Society.)

Objective: To demonstrate the feasibility and effectiveness of extended matching of red blood cells (RBC) in practice., Background: At present, alloimmunisation preventing matching strategies are only applied for specific transfusion recipient groups and include a limited number of RBC antigens. The general assumption is that providing fully matched RBC units to all transfusion recipients is not feasible. In this article we refute this assumption and compute the proportion of alloimmunisation that can be prevented, when all donors and transfusion recipients are typed for A, B, D plus twelve minor blood group antigens (C, c, E, e, K, Fy a , Fy b , Jk a , Jk b , M, S and s)., Methods: We developed a mathematical model that determines the optimal sequence for antigen matching. The model allows for various matching strategies, issuing policies and inventory sizes., Results: For a dynamic inventory composition (accounting for randomness in the phenotypes supplied and requested) and an antigen identical issuing policy 97% and 94% of alloimmunisation events can be prevented, when respectively one and two RBC units per recipient are requested from an inventory of 1000 units. Although this proportion decreases with smaller inventory sizes, even for an inventory of 60 units almost 50% of all alloimmunisation events can be prevented., Conclusion: In case antigen of both donors and recipients are comprehensively typed, extended preventive matching is feasible for all transfusion recipients in practice and will significantly reduce transfusion-induced alloimmunisation and (alloantibody-induced) haemolytic transfusion reactions., (© 2021 British Blood Transfusion Society.)

Background: All SCD patients need extended RBC antigen typing (by serology or genotyping) for provision of extended RH, K matched blood and to guide RBC selection in those with complex transfusion requirements. Genotyping can also identify RH variants which can cause sensitisation even when extended RH phenotypically matched blood is provided and alloantibodies associated with RH variants can cause HTRs., Objectives: To review the use of RBC genotyping in SCD patients at two London trusts (ICHNT, LNWH) with a focus on RH variants., Methods: Retrospective review with data collected from clinical notes, local and national pathology reporting systems., Results: A 311/482 (64%) ICHNT patients and 181/346 (52%) LNWH patients had extended genotyping. Of genotyped patients, 68 (22%) ICHNT and 31 (17%) LNWH patients had RH variants. Eight ICHNT patients had RH variants and corresponding antibodies associated with RH variants; 4/8 received multiple transfusions with antigen positive RBCs but had no evidence of haemolysis. One LNWH patient had a RH variant with corresponding alloantibody but could not be investigated further for possible HTR., Conclusions: Most patients (59%) had genotyping and a significant number had RH variants (99, 20%). A small proportion (9, 9%) had antibodies associated with RH variants, but with no evidence of clinically significant HTRs despite transfusions in four of them with antigen positive RBCs. All SCD patients should have RBC genotyping including RH variants (preferentially over extended phenotyping) to guide better selection of RBC units. However, where antigen negative blood cannot be provided, the risk of alloimmunisation is not inevitable and subsequent HTRs from antibodies associated with RH variants might not always occur., (© 2021 British Blood Transfusion Society.)

Objective: We aimed to assess the frequency distribution of of ABO haemolytic disease of newborn (ABO-HDN) and to know the predictive value of immunohaematological tests in identifying at risk neonates., Background: ABO incompatibility, although a common cause of haemolytic disease of newborn, has several unaddressed issues related to it., Material and Methods: A prospective study over 20 months was carried out in a tertiary care centre in South India. Blood grouping, Direct Antiglobulin test (DAT) and elution studies were performed on neonatal samples, whereas blood grouping, antibody screening and antibody titration were performed on maternal samples. In suspected cases, ABO-HDN was diagnosed after excluding other possible causes for haemolysis. The laboratory results were correlated with the clinical details to assess the predictive value of the tests., Results: Of the total 2856 pregnancies, 34% had ABO incompatibility. On testing with columnagglutination test (CAT), the overall DAT positivity and that among ABO-incompatible cases were 3.8% and 11.2%, respectively,) whereas by conventinal tube technique (CTT) it was 0.6% and 2.4% respectively. CAT was found to have higher sensitivity, and the predictive value was higher for CTT. Maternal IgG titre showed a positive linear relationship with the DAT strength and the rise in indirect bilirubin levels. The positive predictive value of combination of tests such as DAT, elution and titation was 94.12%, which was much higher than that of the individual tests., Conclusion: DAT positivity is a predictor of early rise in serum bilirubin level, and a combination of tests has a better predictive value than individual tests towards development of clinically significant hyperbilirubinemia in ABO-HDN., (© 2020 British Blood Transfusion Society.)

Background: Alloimmunisation and haemolytic transfusion reactions (HTRs) can occur in patients with sickle cell disease (SCD) despite providing phenotype-matched red blood cell (RBC) transfusions. Variant RBC antigen gene alleles/polymorphisms can lead to discrepancies in serological phenotyping. We evaluated differences between RBC antigen genotyping and phenotyping methods and retrospectively assessed if partial antigen expression may lead to increased risk of alloimmunisation and HTRs in SCD patients at a tertiary centre in Canada., Methods: RBC antigen phenotyping and genotyping were performed by a reference laboratory on consenting SCD patients. Patient demographic, clinical and transfusion-related data were obtained from a local transfusion registry and chart review after research ethics board approval., Results: A total of 106 SCD patients were enrolled, and 91% (n = 96) showed additional clinically relevant genotyping information when compared to serological phenotyping alone. FY*02N.01 (FY*B GATA-1) (n = 95; 90%) and RH variant alleles (n = 52, 49%; majority accompanied by FY*02N.01) were common, the latter with putative partial antigen expression in 25 patients. Variability in genotype-phenotype antigen prediction occurred mostly in the Rh system, notably with the e antigen (kappa: 0.17). Fifteen (14.2%) patients had a history of alloimmunisation, with five having HTR documented; no differences in clinical outcomes were found in patients with partial antigen expression. Genotype/extended-phenotype matching strategies may have prevented alloimmunisation events., Conclusion: We show a high frequency of variant alleles/polymorphisms in the SCD population, where genotyping may complement serological phenotyping. Genotyping SCD patients before transfusion may prevent alloimmunisation and HTRs, and knowledge of the FY*02N.01 variant allele increases feasibility of finding compatible blood., (© 2020 British Blood Transfusion Society.)

Objectives: A molecular analysis of serologically RhD variant samples was conducted to find the incidence of various D variants in our blood donor population., Background: Determining a blood donor's RhD phenotype and genotype is important as transfusion of units with a weak D or partial D phenotype can result in immunisation of the recipients., Methods: Samples with discrepant D and weak D phenotypes identified on testing with at least five different monoclonal anti-D antisera were considered serological RhD variant and subjected to molecular testing (Massarray kit, Agena Bioscience, San Diego) for variant RHD gene., Results: A total of 39 samples, including 19 RhD discrepant samples and 20 weak D samples, were identified as serological RhD variant from a total of 4386 samples. Thirteen (13/39) samples carried variants leading to weak D phenotype, and eight samples had variants leading to partial D categories. Seven samples (7) could not be characterised, whereas 11 samples were identified as Rh negative (RHD*01N.01) after molecular testing. Overall incidence of D variants in the study population was 0.48%. RHD*weak D type 1(5, 0.1%) and RHD*DFR1 (5, 1%) were the most common variants identified., Conclusions: Few samples with weak reaction on serological testing were found to be partial D variant and vice versa. Donor centres should develop a protocol for genotyping of samples with aberrant results on serological testing for assessing the actual RhD status of an individual as results of serological testing may be misleading., (© 2020 British Blood Transfusion Society.)

Objectives: The present study aimed to develop strategies for genotyping DO*HY (Dombrock system) and DI*A/DI*B (Diego system) alleles and to evaluate the impact of genomic and self-declared ancestry on rare donor screening in admixed populations., Background: The antigens Hy and Di b demonstrate clinical importance. The lack of antisera for the serological evaluation of these antigens makes it necessary to develop molecular methods. In addition, considering that some rare red blood cell phenotypes present differences in frequency between ethnic groups, it is important to assess the applicability of self-declared ancestry in the search for rare donors in admixed populations., Methods: DO*HY and DI*A/DI*B genotyping based on real-time polymerase chain reaction (PCR) was standardised. A total of 457 blood donors clustered by self-defined skin colour/race categories were genotyped. Furthermore, individual genomic ancestry was used in the analyses., Results: The assays developed are reproducible and provide satisfactory results even at low concentrations of DNA, which make them useful in situations where the DNA is scarce, such as dried blood spots on filter paper, or when screening for pooled samples. No significant difference was observed in the frequencies of the DI*A, DI*B and DO*HY, comparing the self-declared White (branco) donors with those who are Black (preto) and Brown (pardo)., Conclusion: Real-time PCR, especially using pooled samples, is a promising strategy to screen rare blood donors. Although both self-reported race/colour and some blood group phenotypes are associated with ancestry, the results point to a greater complexity in the application of self-declared race/colour in the screening of rare donors in admixed populations., (© 2019 British Blood Transfusion Society.)

Objectives: This study aimed to analyse the allele frequency of blood group antigens in the Korean population and other ethnic populations and the association of blood group antigens with red blood cell (RBC) alloantibodies., Background: Blood group antigen genotyping can support patients undergoing frequent transfusions who have alloantibodies and antibodies against high-prevalence blood group antigens., Methods: Twenty-nine single nucleotide variations and 37 blood group antigens were tested. Samples requested for routine blood typing were collected from Jan to Apr 2016. Genotyping was performed on 145 Korean samples and was confirmed by bidirectional sequencing and serologic tests. The allele frequency data were compared with previous genotyping datasets (three datasets from Korea and one each from China, Europe, Asia, and the USA). Alloantibody frequencies and blood group antigens from the electronic medical record of 1772 cases were examined., Results: E antigen was higher in the Korean population compared to that of Asian and European populations. K, Kp a , Fy b and Do a allele frequencies were lower compared to other ethnic populations. RBC alloantibodies with frequencies (%) greater than 1% from the 1772 cases were as follows: anti-E, 36·7%, anti-C, 17·7%; anti-c 7·39%; anti-M, 5·9%; anti-e, 5·2%; anti-Jk a , 2·9%; and anti-Fy a , 1·1%. Blood group antigens and alloantibody frequencies revealed inverse trends that did not reach statistical significance., Conclusion: The allele frequency of blood group antigens assessed by high-throughput methods provided reliable and valuable information that could be used for maintaining donor pools and providing compatible blood for genotyped patients., (© 2019 British Blood Transfusion Society.)

Aims/objectives: To investigate the underlying molecular mechanism of the patient's ABO typing discrepancy., Background: ABO typing discrepancy was frequently seen in patients due to different causes. In this study, ABO typing discrepancy was found in a 24-year-old man with arthralgia, whose forward ABO grouping was O and reverse ABO grouping was AB. Primary immunodeficiency disease was speculated in this patient, especially X-linked agammaglobulinemia (XLA)., Methods: Immunoglobulins of all isotypes were detected using a specific protein analyser. Lymphocyte subgroups were analysed by flow cytometry. All 19 exons and boundaries of BTK gene were amplified by polymerase chain reaction (PCR), and all PCR products were sequenced by a DNA analyser. BTK protein in the leukocytes and platelets was detected by Western blot., Results: No B lymphocytes could be detected in the peripheral blood of the patient. A novel BTK gene variation, c.817G>T, in the exon 9 of BTK gene was discovered. No BTK protein expression could be detected in the leukocytes and platelets of the patient., Conclusions: XLA could be occasionally discovered by ABO typing discrepancy in some cases because of the deficiency of reciprocal IgM anti-A and/or anti-B antibodies in the serum of the patient. Humoral immunodeficiency is one of the causes of ABO typing discrepancy., (© 2019 British Blood Transfusion Society.)

Objectives: To assess current knowledge of National Heart, Lung and Blood Institutes (NHLBI) and Thalassemia International Federation (TIF) recommendations, blood banking practices and perceived challenges among transfusion services in the management of patients with haemoglobinopathies., Background: Previous reports have demonstrated variations in transfusion practices for sickle cell disease (SCD) and thalassemia patients. Recently, NHLBI/TIF have provided transfusion recommendations for patients with haemoglobinopathies., Methods: A cross-sectional survey was conducted of transfusion services from the state of Georgia previously identified as having SCD/thalassemia populations. The survey assessed transfusion service practices in pre-transfusion testing and blood product selection; awareness/implementation of NHLBI/TIF transfusion-based recommendations and perceived challenges in transfusing haemoglobinopathy patients., Results: Responses were received from 35 of 49 (71%) institutions. Only institutions indicating transfusing SCD or thalassemia patients (32) were included in analysis. Seventy-one percent of non-sickle cell treatment centres (SCTCs) and 20% of non-thalassemia treatment centres follow NHLBI and TIF recommendations to perform a red blood cell phenotype beyond ABO/Rh(D) and provide Rh and Kell prophylactically matched units for SCD and thalassemia patients, respectively. Forty percent of institutions (33% of non-SCTCs) employ RBC genotyping to evaluate the red cell phenotype for SCD patients. Over 77% of institutions do not utilise a reliable method to identify SCD patients prior to transfusion, such as a required question/answer field on type/screen or crossmatch orders., Conclusion: Many healthcare systems' transfusion practices for haemoglobinopathy patients are discordant with NHLBI/TIF recommendations. Efforts are needed to increase awareness and implementation of current recommendations among all transfusion services seeing these patients., (© 2019 The Authors. Transfusion Medicine published by John Wiley & Sons Ltd on behalf of British Blood Transfusion Society.)

Objectives: Next-generation sequencing (NGS) for the determination of rare blood group genotypes was tested in 72 individuals from different ethnicities., Background: Traditional serological-based antigen detection methods, as well as genotyping based on specific single nucleotide polymorphisms (SNPs) or single nucleotide variants (SNVs), are limited to detecting only a limited number of known antigens or alleles. NGS methods do not have this limitation., Methods: NGS using Ion torrent Personal Genome Machine (PGM) was performed with a customised Ampliseq panel targeting 15 different blood group systems on 72 blood donors of various ethnicities (Caucasian, Hispanic, Asian, Middle Eastern and Black)., Results: Blood group genotypes for 70 of 72 samples could be obtained for 15 blood group systems in one step using the NGS assay and, for common SNPs, are consistent with previously determined genotypes using commercial SNP assays. However, particularly for the Kidd, Duffy and Lutheran blood group systems, several SNVs were detected by the NGS assay that revealed additional coding information compared to other methods. Furthermore, the NGS assay allowed for the detection of genotypes related to VEL, Knops, Gerbich, Globoside, P1PK and Landsteiner-Wiener blood group systems., Conclusions: The NGS assay enables a comprehensive genotype analysis of many blood group systems and is capable of detecting common and rare alleles, including alleles not currently detected by commercial assays., (© 2017 British Blood Transfusion Society.)

Objective: The aim of our study was to determine the incidence and causes of ABO typing discrepancies among patients and blood donors at our centre., Background: An accurate interpretation of the ABO blood group of an individual is of utmost importance to ensure patient safety and good transfusion practices., Methods: A retrospective observational study was carried out in the Department of Transfusion Medicine in our hospital from March 2013 to December 2015. Records of all patient and blood donor samples were retrieved and analysed for ABO typing discrepancies., Results: In total, 135 853 patient and 62 080 donor samples were analysed for ABO typing discrepancies. The incidence among patients and blood donors was found to be 0·1% (138/135853) and 0·02% (14/62080), respectively. The mean age for patients and blood donors was 48·4 and 29·2 years, respectively. The most common cause of ABO typing discrepancies was due to cold autoantibodies among the patients (50·7%) and blood donors (57%) causing discrepant results in reverse typing. The various other causes of reverse typing discrepancies among patients were weak/missing antibody (25·4%), cold-reacting alloantibody (4·3%), warm autoantibody (2·2%), anti-A1 antibody (2·2%), Bombay phenotype (1·5%), transplantation (0·7%) and rouleaux (0·7%), whereas in blood donors, the causes were cold-reacting antibody (7%) and weak antibody (7%). The major cause of forward typing discrepancies among patients (12·3%) and blood donors (29%) was ABO subgroups., Conclusion: The resolution of ABO typing discrepancy is essential to minimise the chance of transfusion of ABO-incompatible blood., (© 2018 British Blood Transfusion Society.)

Aims/objectives: The aims of this study were to report a patient with acute haemolytic transfusion reaction (HTR) after transfusing uncross-matched red blood cell (RBC) units and to identify the frequency of this complication., Background: Uncross-matched RBC units are commonly transfused in emergencies, but the frequency of acute HTR is unknown., Methods: We describe a male stabbing victim who received three units of uncross-matched RBC units complicated by acute intravascular HTR, disseminated intravascular coagulation (DIC) and renal failure. We identified 14 studies evaluating the frequency of acute HTR post-emergency transfusion of uncross-matched RBC units., Results: Acute HTR was shown by haemoglobinuria, free-plasma haemoglobin and methemalbumin, with anti-K and anti-Fy a eluted from recipient red cells; acute DIC featured severe hypofibrinogenemia, thrombocytopenia, elevated fibrin D-dimer and multiple bilateral renal infarcts. Two of the three transfused units reacted with pre-existing RBC alloantibodies [anti-K (titre, 128), anti-Fy a (titre, 512)], explained by transfusion 25 years earlier. Our literature review found the frequency of acute HTR following emergency transfusion of uncross-matched RBC units to be 2/3998 [0·06% (95% CI, 0·01-0·21%)]., Conclusions: Although emergency transfusion of uncross-matched blood is commonly practiced at trauma centres worldwide, with low risk of acute HTR (<1/1000), our well-documented patient case demonstrates the potential for acute HTR with severe complications., (© 2018 British Blood Transfusion Society.)

Background: The development of specific antibodies against human leukocyte antigen (HLA) and/or human platelet antigen (HPA) could induce platelet transfusion refractoriness especially in patients receiving multiple platelet transfusions. A retrospective analysis was conducted to evaluate the prevalence of platelet-specific antibodies and the efficacy of crossmatch-compatible platelet transfusions in these recipients., Study Design and Methods: All enrolled patients were refractory to random single-donor apheresis Platelet (PLT) units. Enzyme-linked immunosorbent assay (ELISA) was used to detect anti-HLA and anti-HPA antibodies in serum. For those patients with antibodies, the PLT crossmatch assays were performed to select the compatible PLTs with a commercial solid-phase adherence kit., Results: A total of 193 patients were included and 29.02% of which was HLA and/or HPA antibody-positive. There were no significant differences in antibody-positive rates among AML/CML, ALL/CLL, MDS, SAA and ITP groups, but they are statistically significantly higher than other groups (P = 0.0035). Of those antibody-positive patients, there were 41 (73.21%) patients with only HLA antibodies, 11 (19.64%) patients with only HPA antibodies and 4 (7.14%) patients with both HLA and HPA antibodies. A total of 43 random PLT units and 88 crossmatch-compatible PLT units were administered. The mean (± SD) corrected count increment (CCI) was 8700 (± 4500) after crossmatch-compatible unit transfusion, significantly higher than 3600 (± 2400) for random PLT units (P < 0.001)., Conclusions: HLA and/or HPA alloimmunisation is an important factor to cause refractoriness to platelet transfusions. Crossmatch-compatible platelet transfusion is an effective method in those patients refractory to random platelet transfusions., (© 2014 British Blood Transfusion Society.)

Background and Objectives: Blood incompatibility arises from individual and ethnic differences in red blood cell (RBC) antigen profiles. This underlines the importance of documenting RBC antigen variability in various ethnic groups. Central Asia is an area with a long and complex migratory history. The purpose of this article is to describe key antigen frequencies of Afghan ethnic groups in the Hindu-Kush region of Afghanistan as a basis for improving blood transfusion practices in that area., Materials and Methods: The key ABO, Rh and Kell antigens were investigated in five Afghan populations. In order to depict accurately the blood group gene diversity in the area, DNA from eight additional Pakistani populations were included, and the entire sample set screened using two multiplex polymerase chain reactions sensitive for 17 alleles in 10 blood group genetic systems (MNS, Kell, Duffy, Kidd, Cartwright, Dombrock, Indian, Colton, Diego and Landsteiner-Wiener)., Results: Phenotype and allele frequencies fell within the ranges observed in Western European and East Asian populations. Occurrence of DI*01, IN*01, LW*07 and FY*02N.01 and prevalence of ABO*B were consistent with migratory history as well as with putative environmental adaptation in the subtropical environment Hindu-Kush region., Conclusion: These findings expand the current knowledge about key antigen frequencies. Regarding occurrence of viral markers, further blood transfusion in the region requires rigorous typing., (© 2013 The Authors. Transfusion Medicine © 2013 British Blood Transfusion Society.)

Background: Most studies of the molecular basis of Rhesus D-negative phenotype have been conducted in Caucasian and African populations. A comprehensive survey of RHD alleles was lacking in people from North Africa (Tunisians, Moroccans and Algerians) which could be very efficient for managing donors and patients carrying an RHD molecular variant. We analyse the molecular background of D-negative population in Tunisia in the present study., Materials and Methods: Blood samples were collected from native Tunisians. A total of 448 D-negative donors from different regions of Tunisia were analysed by RHD genotyping according to an adopted strategy using real-time PCR, ASP-PCR and sequencing., Results: Among the 448 D-negative samples, 443 were phenotyped unequivocally as true D-negative including three molecular backgrounds which were RHD gene deletion (n = 437), RHDψ pseudogene (n = 2) and RHD-CE-D hybrid gene (n = 4) with the respective frequencies of 0·9900, 0·0023 and 0·0046. The remaining five samples, in discordance with the serological results, were identified as two weak D type 11, one weak D type 29, one weak D type 4·0 and one DBT-1 partial D., Conclusion: This study showed that the Tunisian population gets closer to Caucasians, given that the RHD gene deletion is the most prevalent cause of D-negative phenotype, but it is slightly different by the presence of the RHDψ pseudogene which was found with a very low frequency compared with that described in the African population. Nevertheless, the relative occurrence of weak D variants among studied serologically D-negative samples make necessary the adaptation of RHD genotyping strategy to the spectrum of prevalent alleles., (© 2012 The Authors. Transfusion Medicine © 2012 British Blood Transfusion Society.)

Sometimes commercial RBC sets for the screening of irregular antibodies contain Wr(a+) cells. The aim of this study was to define the usefulness of employing RBC sets for the screening of irregular antibodies containing Wr(a+) cells in pre-transfusion tests. Anti-Wr(a) is a relatively common naturally occurring antibody in candidates to blood transfusion, although the risk of receiving a non-compatible unit is low. We have studied both the incidence of Wr(a) antibodies and the effects of having a Wr(a+) cell in the screening test on routine work in an unselected population of 787 patients requiring RBC transfusion and in 151 new blood donors. Irregular antibodies were found in 64 sera, 58 of which were specific for Wr(a) , 46 (5·8%) and 12 (7·9%) in patients and donors, respectively. The positive tested sera contained specific IgM in 16 cases, IgM + IgG in 13 cases and IgG in 27 cases. Anti-Wr(a) can usually be detected during cross-match procedures; therefore, the presence of Wr(a+) cells in pre-transfusion screening of blood recipients is not justified and it causes an undue increase in cost and time to unit release. Moreover, because of the rare association between anti-Wr(a) and haemolytic transfusion reaction, the use of Wr(a+) RBC-containing sets is also questionable in the countries that do not perform pre-transfusion cross-match tests., (© 2010 The Authors. Transfusion Medicine © 2010 British Blood Transfusion Society.)

As there were no reliable data in Malawi for the prevalence of red cell alloantibodies or antigens in the population, a study was conducted to screen 1000 patients for the presence of antibodies and to type them for ABO, RhD, C, c, E, e and K antigens and to test 500 donors for these antigens plus Fy(a), Fy(b), Jk(a), Jk(b), S and s. Red cell antibodies were identified in 11 patients [1.1%]; 2 were anti-D, 2 anti-S, 1 anti-Le(a+b) and 6 anti-M, 4 of which were found in non-transfused males suggesting they might be naturally acquired. The antigen frequencies found were similar to those previously published for Central Africa but 98.2% of donors were found to be Fy(a-b-). All patients tested were K negative and only three donors were found to be K positive, one being a Caucasian. Approximately 3.5% of Malawians are D negative, lower than the usual 8% quoted for Black Africans. These data confirm the assumption that pre-transfusion antibody screening is not currently required but that use of the indirect antiglobulin test in the cross-match is necessary. Haemolytic disease of the newborn (HDN) appears to be rare, or under reported, in Malawi, and more work is needed to find the real incidence of this condition.

Objectives: Gene frequencies of human platelet antigens (HPA) determine the magnitude of platelet immunological disorders like neonatal alloimmune thrombocytopenia, platelet refractoriness and ease of availability of particular HPA-typed platelet donors in a given community., Background: However, the pattern of HPA in Pakistani population is not known., Aim: The aim of present study was to determine the gene frequencies of HPA (HPA-1 to -5 and -15) in individuals belonging to major ethnic groups and castes of Pakistani population., Materials and Methods: HPA genotyping was done in 593 individuals belonging to all ethnic groups of Pakistan, by polymerase chain reaction-sequence specific primers with detection on polyacrylamide electrophoresis., Results: The gene frequencies of the 'a' and 'b' alleles of HPA-1 to -5 and -15 in Pakistanis were as follows: HPA-1a/b, 0.885/0.115; HPA-2a/b, 0.92/0.08; HPA-3a/b, 0.69/0.31; HPA-4a/b, 1/0; HPA-5a/b, 0.9/0.1; HPA-15a/b, 0.59/0.41. Except for significant difference regarding gene frequency of HPA-3 between Pathans and Sindhis, there was no significant difference of HPA-1 to -5 and -15 between major ethnic groups of Pakistan. The estimated mismatch probability regarding platelet antigens 1-5 and 15 in Pakistanis, after transfusion of random donor platelets, is from 14 to 37%. The expected incidence of neonatal alloimmune thrombocytopenia due to anti-HPA-1a in Pakistani pregnant females is < 1 of 1000 pregnancies and 8-12 of 1000 in case of anti-HPA-5b. Homozygosity of HPA-1b, -2b and -5b genotypes ranged from 1 to 2% in the Pakistani population, whereas homozygosity of HPA-3b and -15b was 11 and 18%., Conclusions: There is a need to establish donor registries typed for HPA in the transfusion centres of the country.

HDN attributed to the rare Rh variants has become more and more significant caused by anti-D, but the compatible blood is usually very difficult to obtain when exchange transfusion is required. We treated a 10-hour neonate of O, D + C + c - E - e+ blood group with severe HDN due to anti-Rh17 with least incompatible blood typed O, D + C - c + E + e-. The neonatal hemolysis was relieved obviously and bilirubin was reduced gradually after exchange transfusion. The infant was discharged in good health 13 days after birth with 135.0 g/L, 28.0 micromol/L and 10.7 micromol/L of Hb, total bilirubin and direct bilirubin, respectively. No sequelae were observed in a three-year follow-up. The result suggesting that the least incompatible blood is an alternative choice for exchange transfusion in severe HDN due to anti-Rh17 in case that Rh17 antigen-negative blood is unavailable.

A 26-year-old Caucasian female in her second pregnancy grouped as A, D+ R(1)R(1) K- with anti-K (titre: 256) at booking. Her partner was typed as K1 positive. Baby was born with Hb 23.1 g/dl. Cord samples were referred to our laboratory for investigation and were found to be DAT 5+, IgG and anti-K was eluted from the red cells. Cord samples typed as A, R(1)r K- by DiaMed DiaClon Rh subgroups & K card. We report a case of false negative K1 phenotyping due to blocking with maternal anti-K.

Transfusion management of patients alloimmunized against high-prevalence erythrocyte antigens is often problematic in emergency situations. In these patients, incompatible transfusion may be less harmful for the patient than delaying surgery, especially if the antibody is not clinically significant. We report an untransfused 75-year-old Caucasian man (blood group O) with an alloantibody against the Gerbich-2 (Ge2) antigen who required emergency cardiac surgery. Because cross-match compatible blood was not available in an acceptable timeframe, we performed a 'biological cross-match' with sequential transfusion of 20 and 50 mL and then the entire unit of incompatible red blood cells (RBCs) before surgery. When there were no clinical symptoms of adverse biological effects, we transfused two further incompatible packed RBCs during surgery. Subsequently, there was neither clinical nor laboratory evidence of major intra- or extravascular haemolysis, suggesting that this anti-Ge2 antibody was not clinically significant.

The objective was to assess both our local plan and the assumptions made in the national guidelines on how laboratories should prepare for an acute shortage of red cells. The Chief Medical Officer's National Blood Transfusion Committee for England and North Wales has issued guidance on how hospitals should prepare contingency plans to deal with a shortage of red cells for transfusion. This study has therefore assessed the practicalities of these proposals together with assessing how well local policies would deal with this situation. A tabletop exercise was carried out in which all requests over a 21-day period were assessed. The restrictions as suggested by the national blood transfusion committee were applied and the impact on the blood stocks during an acute blood shortage was assessed. The results show that application of the national guidelines on the restriction of the use of red cells during an acute blood shortage resulted in all transfusion requests for red cells being met. We also appear to have shown that the assumptions made by the national transfusion team are realistic. Carrying out a tabletop exercise is a useful method to assess local procedures for dealing with an acute reduction in the supply of red cells.

Recently, evidence implicating the roles of the anti-human leucocyte antigen (HLA) class II antibody in the development of transfusion-related acute lung injury (TRALI), which is one of the most serious possible side effects of transfusion, has been accumulating. The aim of this study is to clarify the roles of the anti-HLA DR alloantibody in TRALI development. Cultured human lung microvascular endothelial (LME) cells were incubated with either HLA-DR15-positive or HLA-DR15-negative monocytes together with serum from a single multiparous donor previously implicated in a clinical case of TRALI and known to contain anti-HLA DR15 antibody. Production of soluble leukotriene B(4) (LTB(4)) was measured in the supernatant and found to be markedly increased in the presence of HLA-DR15-positive monocytes but not with the HLA-DR15-negative monocytes or in the absence of LME cells. The vascular cell adhesion molecule-1 expression in LME cells and leucocyte-function-associated molecule-1 (LFA-1) expression in HLA-DR15-positive monocytes were notably enhanced after combined culture of LME cells, HLA-DR15-positive monocytes and TRALI-inducing anti-HLA DR15 antibody-positive serum. In conclusion, anti-HLA DR alloantibodies may be implicated in LME dysfunction that leads to TRALI, in a monocyte-dependent manner.

Aim: To determine the availability of donor hearts for children of different blood group and weight needing urgent heart transplantation., Methods: Data maintained by the Australia and New Zealand Organ Donor Registry 1989-2004 were analysed to determine the frequency of donation. Probabilities of suitable donor availability within 10, 20, 30, 40, 60, 90 and 180 days were estimated using a Poisson model with the assumptions that traditional ABO blood compatibilities applied, suitable donors were 0.8-4.0 times the recipient's body weight (BW) and suitable adult donors were aged <40 years., Results: Probabilities of suitable donor availability increase with passage of time from 10 to 180 days and decrease with competition from other needful recipients. Maximum suitable donor availability occurs for children of all blood groups at body weight 20 kg. The probabilities of a donor heart arising within 40 days (maximum safe duration of extracorporeal membrane oxygenation support locally available for young children) for this recipient body weight according to blood group is 0.89, 0.85, 0.73, 0.67 (AB, A, B, O). Probabilities for recipients of BW 3 kg and 60 kg respectively are 0.16, 0.14, 0.10, 0.09 (AB, A, B, O) and 0.66, 0.61, 0.47, 0.42 (AB, A, B, O)., Conclusion: Expectation of suitable heart donation arising within 40 days for needful recipients in Australia is low for infants (probability <0.3), moderate for small children (probability 0.5-0.9) and modest for large children (probability 0.4-0.7), with variation at all body weights according to blood group and waiting time.

Objectives: To determine the distribution of blood types and to estimate the proportion of matings at risk for neonatal isoerythrolysis in non-pedigree domestic cats., Methods: The present survey determined the frequency of blood types in 301 cats from four distinct regions of Turkey. Ethylenediaminetetraacetic acid-anticoagulated blood samples were typed by simple tube and slide agglutination assays. Serum obtained from type B cats and an anti-B solution, prepared with Triticum vulgaris, were used to determine type A and type B blood, respectively., Results: Of the 301 cats typed, 220 had type A blood, 74 had type B and seven had type AB. There was a significant difference (P<0.01) between the locations of the cats, with fewer type B cats in the eastern than in the western parts of Turkey. Risk for the development of neonatal isoerythrolysis due to A-B mismatch was estimated to be 18.6 per cent., Clinical Significance: The overall type B frequency in Turkish domestic cats is high. Thus, untyped transfusions in these cats carry a high risk of life-threatening acute haemolytic transfusion reactions and neonatal isoerythrolysis. It is therefore strongly recommended that blood typing be performed before breeding or transfusing in order to minimise blood type incompatibility risks.

Guidelines for the prevention and management of red cell alloantibodies during pregnancy, related to anti-D in particular, are well established in Caucasian populations. However, because of the racial difference of the blood group distribution, applicability to Chinese is unknown as a result of insufficient data on the prevalence and their outcome. In a retrospective review of 28,303 (21,327 Chinese) antenatal attendances from 1997 to 2001, 213 (0.79%) women were found to have a total of 230 irregular antibodies. About 137 (0.64%) were ethnic Chinese, and a total of 160 irregular antibodies were identified in their blood samples. About 58 of these Chinese women (0.27%) were found to have 66 clinically significant antibodies. There was only one case of anti-D detected in an Rh(D)-negative subject. Our study shows the overall prevalence of clinically significant antibodies in Chinese women, which was not different from that of the Western population. However, the specificities of the antibodies differ with the commonest antibodies encountered; these being anti-Mi (57.6%), anti-E (19.7%), anti-S (10.6%) and anti-c (7.6%). Neonatal jaundice was observed in 37 babies and 10 of them required phototherapy. The findings support the previous recommendation that routine antenatal antibody screening for Chinese women may not be worthwhile except in Rh(D)-negative subjects or those with an antecedent history of haemolytic disease of the newborn (HDN). The relative high incidence of anti-Mi in the present study and the local population, in general, may warrant a large-scale prospective study of pregnancy outcome in these subjects, especially in the light of the previous case reports of HDN because of anti-Mi.

Anti-'Mia' is the most common alloantibody of potential clinical significance in the Taiwanese population. The Mi.III phenotype is rare among Caucasians but has a high incidence in various Oriental populations. We describe a nulliparous woman with no history of transfusions, who had hydrops foetalis at 28 weeks gestation. Foetal haemoglobin was 4.4 g dL-1, and a positive direct antiglobulin test was positive in the foetal blood. Intrauterine intravascular transfusion was given, and the baby was discharged healthy. Anti-'Mia' was identified in the maternal serum, the cord blood serum and the eluate from red cells of the cord blood. Anti-'Mia' in the maternal serum was confirmed to be anti-Mur. The polymerase chain reaction-restriction fragment length polymorphism method confirmed that both the baby and her father had the Mi.III gene. Therefore, our report documents that anti-Mur has the potential to cause hydrops foetalis.

We have investigated a 'new' low frequency antigen JAHK, which is a marker for the rare Rh gene complex rG. The rG haplotype does not produce any D, c or E antigens, but does produce a strong G antigen. The rG haplotype [d(C)(e)G] is associated with weak C and weak e antigens. Three unrelated rG/dce individuals and one rG/rG propositus were JAHK+. In addition, three propositi whose red cells had a typical expression of C and/or e antigen, which could not be shown to be rG because of a normal D antigen produced by the haplotype in trans, were also JAHK+. Families of three of the propositi demonstrate the inheritance of JAHK as a Mendelian dominant character. It is likely that the JAHK antigen results from conformational changes in an RhCcEe protein that has the amino acid characteristic of c antigen at position 16 and the amino acid residues characteristic of C antigen at positions 60, 68, and 103. JAHK has been assigned the number RH53.

We have investigated the role of major histocompatibility complex (MHC) (RT1) disparities in the engraftment of bone marrow (BM) cells after whole body irradiation of rats. Mononuclear BM cells from PVG.RT7.2 (RT1c) rats were injected i.v. into sublethally (10Gy) whole body irradiated PVG (RT1c) rats and RT1 congenic and recombinant PVG rats. Repopulation of the BM, spleen, and blood with donor cells was assessed by FACS analysis of cells labelled with the fluorescein isothiocyanate (FITC)-labelled HIS41 monoclonal antibody (MoAb) against the RT7.2 marker. In RT1 matched (PVG.RT7.2 --> PVG) and RT1-mismatched combinations (PVG.RT7.2 --> PVG.1AV1), where radioresistant host natural killer (NK) cells could not recognize the BM inoculum as foreign, a donor chimerism close to 100% was observed after 6-8 weeks. However, in rat strain combinations where host NK cells could recognize an RT1 mismatch, almost no donor cells survived, and the rats were repopulated with leukocytes of host origin. In intra-MHC recombinant rat strains the element determining rejection or acceptance of the allograft mapped to the RT1-B/D-C/E/M region in PVG.R8 and PVG.R23 rats, in accordance with the patterns of NK alloreactivity in these strain combinations. NK cells may therefore be a primary obstacle to successful allogeneic BM engraftment in this model.

Fatal haemolytic transfusion reaction due to ABO incompatibility occurs mainly as a result of clerical error. A blood sample drawn from the wrong patient and labelled as another patient's will not be detected by the blood bank unless there is a previous ABO grouping result. We report here the detection of such clerical error by the use of a specially designed transfusion wristband. The wristband has the following special features: (i) once attached, it cannot be removed except by cutting; (ii) it has a pocket containing a transfusion label; (iii) a unique transfusion barcode is printed on each transfusion label and the corresponding wristband simultaneously by computer technology; (iv) a transfusion label removed from the wristband after attachment to the patient has a characteristic tear-mark distinguishing it from one removed prior to attachment. The blood bank only accepted those specimens bearing the tear-marked transfusion labels. All blood units for this patient were labelled with this unique transfusion code together with the patient's details. The nurses counter-checked the transfusion code on the blood units against the transfusion code on the patient's transfusion wristband prior to transfusion. If the blood sample for compatibility testing was drawn from the 'wrong' patient, the intended patient either did not carry a wristband or the transfusion codes did not match at all. Pretransfusion compatibility tests were performed on 2189 patient samples using this procedure. It was well accepted by both ward and blood bank staff. Two potential mismatched transfusions were avoided. These two clerical errors would not have been detected because neither patient had previous ABO grouping results.

We perform a retrospective study to determine the incidence and characteristics of alloimmunization in Chinese patients with warm autoimmune haemolytic anaemia. Among 67 patients studied, clinically significant alloantibodies were found in only eight patients, giving a rate of alloimmunization of 11.3%. The latter contrasts with the much higher rate reported in the Western population. This probably reflects the genetic homogeneity in Chinese with respect to the red cell phenotype. The alloimmunization rate, however, is still significant and therefore comprehensive pretransfusion testing is required for Chinese patients with warm autoantibodies so as to safeguard patient's safety.

The molecular characterization of the subgroup A3 remains unclear. Four unrelated A3 blood donors were studied. Family studies were possible in three of them. The A3 subgroup was defined by immunohaematological evaluation with four different commercially available serums. Exons VI and VII of the ABO gene, responsible for 91% of the catalytic active part of the glycosyltransferase, were amplified and subjected to direct sequencing. The results in all samples showed heterozygosity for the G261 deletion. In the A3 allele, the following associations were found: C467T mutation and 1060C deletion in one A3 blood donor and in another G829A and 1060C. In one case, only the 1060C deletion was demonstrated in the A3 allele. One blood donor presented the T646A and the G829A mutations in homozygosity. It was concluded that the A3 blood group is very heterogeneous at the molecular level.

We have audited the error rates of our transfusion laboratory and compared these with error rates reported in the transfusion literature. Error rates were calculated using workload data from the department. The majority of errors that were detected were preanalytical and related to inadequate or incomplete data provided on the sample or request form. These errors were all corrected prior to any further action being taken on that request. The main analytical errors were transcription errors in entering patient identification information into the laboratory computer by transfusion staff together with the incorrect performance of blood group testing. For postanalytical errors the main errors were failure of nursing staff to follow procedures for the collection of blood components prior to transfusion. There were no serious consequences identified of the errors detected in this study. It was difficult to compare these results with those published in the literature in view of the different methodologies that have been reported when error rates have been determined. A standard method should be developed in the UK for calculating error rates so that laboratories can benchmark their performance against comparable organizations.