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Objective We aimed to simplify our fetal RHD genotyping protocol by changing the method to attach Illumina’s sequencing adaptors to PCR products from the ligation-based method to a PCR-based method, and to improve its reliability and robustness by introducing unique molecular indexes, which allow us to count the numbers of DNA fragments used as PCR templates and to minimize the effects of PCR and sequencing errors. Results Both of the newly established protocols reduced time and cost compared with our conventional protocol. Removal of PCR duplicates using UMIs reduced the frequencies of erroneously mapped sequences reads likely generated by PCR and sequencing errors. The modified protocols will help us facilitate implementing fetal RHD genotyping for East Asian populations into clinical practice.

Purpose To evaluate the diagnostic accuracy of a commercially available test kit for noninvasive prenatal determination of the fetal RhD status (NIPT-RhD) with a focus on early gestation and multiple pregnancies. Methods The FetoGnost RhD assay (Ingenetix, Vienna, Austria) is routinely applied for clinical decision making either in woman with anti-D alloimmunization or to target the application of routine antenatal anti-D prophylaxis (RAADP) to women with a RhD positive fetus. Based on existing data in the laboratory information system the newborn’s serological RhD status was compared with NIPT RhD results. Results Since 2009 NIPT RhD was performed in 2968 pregnant women between weeks 5 + 6 and 40 + 0 of gestation (median 12 + 6) and conclusive results were obtained in 2888 (97.30%) cases. Diagnostic accuracy was calculated from those 2244 (77.70%) cases with the newborn’s serological RhD status reported. The sensitivity of the FetoGnost RhD assay was 99.93% (95% CI 99.61–99.99%) and the specificity was 99.61% (95% CI 98.86–99.87%). No false-positive or false-negative NIPT RhD result was observed in 203 multiple pregnancies. Conclusion NIPT RhD results are reliable when obtained with FetoGnost RhD assay. Targeted routine anti-D-prophylaxis can start as early as 11 + 0 weeks of gestation in singleton and multiple pregnancies.

Background and objective Routine antenatal anti-D prophylaxis (RAADP) to RhD-negative women is most often administered in gestational age (GA) 28-30 weeks with the next anti-D dose administered postpartum. The aim of this study was to analyse the proportion of RhD-negative women where RAADP is not detectable at term and in a pilot study to investigate whether RAADP administered in GA 28 and 38 results in detectable levels at term, post-term and post-delivery. Materials and methods In a retrospective analysis, 4280 RhD-negative women carrying an RHD positive fetus were included and the proportion with a negative antibody screen at delivery was determined. In the second part, 39 pregnancies were included prospectively, a second dose of RAADP was administered in GA 38 weeks, and anti-D was quantified before the second dose and then weekly for 5 weeks. Results In the retrospective analysis, 20·5% (856/4280) with RAADP administered in GA 28 were negative in routine antibody screening at delivery. In the small prospective study, 18% (7/39) had a negative antibody screen and 26% (10/39) had levels below 0·005 IU/ml, in the quantification assay, in GA 38. Anti-D prophylaxis administered in GA 38 showed detectable levels of anti-D up to 30 days post-delivery, with concentration at delivery 0·060 ± 0·034 IU/ml (mean ± SD). Conclusion Approximately 20% of the RhD-negative women show non-detectable levels of anti-D at term. A second dose of RAADP at GA 38 results in stable concentrations of anti-D at term, post-term and post-delivery, but with large interindividual variation.

The frequency of Rhesus D negative blood group in Omanis is 8.35% but the molecular background of this phenotype is unknown in the Omani population. The Rhesus D negative phenotype has a high molecular diversity. We report a rare case of serological D negative with existence of complete RHD gene in a 43-year-old Omani male blood donor. Molecular analysis of RHD exons showed duplication across the boundary of intron 3 and exon 4. This is a 37 bp insert in RHD exon 4 along with c.609 G>A mutation. We are uncertain if the presence of RHDΨ is homozygous (RHDΨ/RHDΨ) or hemizygous (RHDΨ/del). Therefore, molecular basis of D zygosity determination would be a good approach to further explore the case.

Background: The WHO recommends that pre-transfusion testing should include ABO/RhD grouping followed by screen- ing for red blood cell (RBC) alloantibodies using the indirect antiglobulin test (IAT). However, in Uganda, current practice does not include RBC alloantibody screening. Objective: To assess the utility of ‘home-made’ reagent RBCs in alloantibody screening. Materials and methods: In a laboratory-based study, group O RhD positive volunteer donors were recruited and their extended phenotype performed for C, c, E, e, K, Fya, Fyb Jkb, S and s antigens. These ‘home-made’ reagent RBCs were preserved using Alsever’s solution and alloantibody detection tests performed. For quality assurance, repeat alloantibody screening of patients’ samples was done at Bloodworks Northwest Laboratory in Seattle, United States. Results: A total of 36 group O RhD positive individuals were recruited as reagent RBC donors (median age, 25 years; range, 21 – 58 years; male-to-female ratio, 1.6:1). Out of the 311 IATs performed, 32 (10.3%) were positive. Confirmatory IAT testing in the United States was in agreement with the findings in Uganda. Conclusion: Use of ‘home-made’ reagent RBCs during pre-transfusion testing in Uganda is feasible. We recommend the introduction of pre-transfusion IAT alloantibody screening in Uganda using ‘home-made’ reagent RBCs to improve trans- fusion safety. Keywords: Blood transfusion; ‘Home-made’ reagent RBCs; Pre-transfusion testing; RBC alloantibody screening; Uganda.

Human platelets do not express any antigens of the Rhesus system. However, platelet concentrates contain the variable volume of contaminating RBCs, which may induce RhD alloimmunization when transfused in a RhD negative subject. Though low rate of anti-D alloimmunization related to platelet transfusion, the development of RhD and non-RhD antibodies cannot be ignored. Thus, transfusion practices could allow the transfusion of RhD positive platelet units to RhD negative patients, with the exception of females of childbearing age. Keywords: Platelet, Transfusion, Alloimmunization, Donor, Antibody, Antigen.

of the study is to research the epidemiological aspects of maternal alloimmunization against erythrocyte antigens of fetuses (AB0, Rhesus, Lewis, Kell, Duffy and others) and to identify the most common types of hemolytic disease of the newborn (HDN) in the West Herzegovina region.The 20-year retrospective epidemiological study includes all pregnant women who had been immunologically tested and newborn treated for HDN.The indirect antiglobulin (IAT) detected antibodies against antigens in 545 (1.8%) pregnant women of the 29 663 who were tested at the Department of Transfusion Medicine. During the 20-year-long study 310 (1.0%) newborn with HDN were treated. Our results indicate that 42% (230/545) of the pregnant women had AB0 immunization. The most common form of HDN is AB0 HDN 64% (199/310), whereas RhD HDN was treated in 19% (59/310) of the newborn infants. ETR was performed on 29 (19%) infants, 21 (72.4%) with AB0 HDN, and 7 (26%) with RhD HDN.This 20-year-long study concludes that, even though there has been significant progress in the prevention of immunization and proactive treatment of HDN, precautionary measures are still required as is the need for gynecologists and obstetricians to be active. The reasons for this are the non-existence of preventive measures for non-RhD immunization, the irregular immunological screening of RhD positive women in pregnancy in the region encompassed by the study in the past few years. The above raises new questions and recommends further research and monitoring of immunization and HDN treatment worldwide.ZIEL DIESER STUDIE: war die Untersuchung von epidemiologischen Aspekten mütterlicher Immunisierung gegen fetale Erythrozytenantigene(AB0, Rhesus, Lewis, Kell, Duffy und andere) und die Feststellung von häufigsten Ursachen der hämolytischen Erkrankung des Neugeborenen (MHN) in der Region der West-Herzegowina.20-jährige retrospektive epidemiologische Studie umfasste alle Schwangeren, die immunologische getestet sowie Neugeborene, die wegen MHN behandelt wurden.Durch den indirekten antiglobulin Test (IAT) wurden bei 545 (1,8%) Schwangeren Antikörper gegen Antigene nachgewiesen, von 29 663 Probanden, die an der Transfusionsanstalt UHC Mostar getestet wurden. Während der zwanzigjährigen Studie hatten 310 (1,0%) Neugeborene MHN. Unsere Ergebnisse zeigten, dass 42% (230/545) der Schwangeren die AB0-Immunisierung hatten. Die häufigste MHN bei dieser Forschung war die AB0 MHN 64% (199/310), während RhD MHN bei 19% (59/310) der Neugeborenen behandelt wurde.Die Blutaustauschtransfusion (ETR) erfolgte bei 29 (19%) Neugeborenen, 21 (72,4%) bei Neugeborenen mit AB0 MHNund 7 (26%) mit Rh D MHN.Obwohl es zu während dieser 20-jährigen Studie zu einem bedeutenden Fortschritt bei der Vorbeugung der Immunisierung und der proaktiven MHN-Behandlung kam, erfordert es weiterhin Vorsichtsmaßnahmen und die Aktivitäten der Gynäkologen und Neonatologen. Grund dafür ist das Nichtbestehen von Vorbeugungsmaßnahmen zur nicht-RhD Immunisierung (67% der Schwangeren hatten Nicht-RhD Antikörper), unregelmäßiges immunologisches Testen von RhD-positiven Schwangeren in den letzten Jahren im Untersuchungsgebiet. All dies eröffnet neue Fragen und Empfehlungen zur Erforschung und Beobachtung der Immunisierung sowie MHN-Behandlung auf der globalen immunologischen Szene.

Background and Objectives: The frequencies of clinically significant blood groups antigens (Rh, Duffy, Kell, Kidd, MNS, P and Lewis) should be known to BTS to manage patients with clinically significant antibodies. This study was conducted to help develop in-house cell panels to manage such patients. Methods and Materials: A total of 331 donors with O blood group with age group of 18 to 45 years, repeatedly donating blood were included in the study. They were screened for antigens of Rh, Kell, Kidd, Duffy, MNS, P and Lewis blood group system. Results: Among 331 donors, 299 (90.3%) donors were RhD Positive. e antigen was prevalent in 328 (99.1%) donors. Only 2 (3.5%) donors with E antigen were lacking D antigen also. All D negative donors (9.7% of total donors) were having strong expression of c and e antigen on their red cells. In Kell system, 100% donors were k antigen positive. All K positive donors are also positive for D antigen. In Kidd and Duffy system, Jka and Fya are more prevalent. In Lewis system, Lea-Leb+ (66.5%) is the commonest phenotype. In MNS system, M antigen was present in 87.61% of donors and s antigen in 83.38% of donors. Conclusions: Knowledge of red cell antigen phenotype frequencies in a population is helpful in terms of their ethnic distribution, in creating a donor data bank for preparation of indigenous cell panels, and providing antigen negative compatible blood to patients with multiple alloantibodies.

OBJECTIVE To determine the occurrence of and risk factors for fetomaternal hemorrhage (FMH) among pregnant women at Korle Bu Teaching Hospital in Accra, Ghana. METHODS A prospective study of FMH among pregnant women without hemoglobinopathies in the second trimester attending prenatal care between October 2015 and May 2016 performed using the Kleihauer-Betke test. Volume of FMH was estimated; ABO and Rh blood groups of participants were determined. A data extraction form and structured questionnaire were used to collect demographic and clinical information, and data on risk factors. RESULTS Of 151 participants, 32 (21.2%) had FMH. Almost 18% (n=27) had FMH at baseline (16-24 weeks), 10% (10/100) at 28-32 weeks, and 11.1% (11/99) at 34-37 weeks of pregnancy. Volume of FMH was less than 30 mL in 30 (19.9%) women, whereas it was greater than 30 mL in 2 (1.3%) women. No identifiable patient-specific factors were associated with occurrence of FMH. CONCLUSION FMH is common among pregnant women in Ghana and can occur as early as 16 weeks, without identifiable risk factors. RhD negative women who may be pregnant with RhD positive fetuses should be screened early in pregnancy, not only at delivery, for occurrence of FMH.

Background: Most people are either RhD positive or RhD negative, but there is also a number of persons with D antigen variants. The aim of this study was to prove, by using molecular diagnostic tests, whether the RHD gene and D antigen on the red cell membrane of the blood donors serologically typed as RhD-negative with RhD phenotype Ccddee and ccddEe, are so weak that they cannot be proven by serology techniques or the available anti-D test serums. Methods: Samples used are those of regular voluntary donors who were serotyped as RhD-negative, C and/or E positive. Samples were collected from voluntary donors at the Institute for Transfusion Medicine of the Republic of Srpska during the period from April 2016 to December 2018. Results: Among the serologically proven RhD-negative donors, 346 had C and/or E in their phenotype and those were subjected to molecular screening test. Conclusion: The first results of molecular typing match those published in literature, i.e. the RHD gene is present in some serologically RhD-negative forms, which was proven by molecular testing.

Introduction Early transfusion reduces mortality in bleeding patients. In this setting, RhD-positive blood products might be transfused. This study determined the association between the RhD-alloimmunization rate and the number of RhD-positive products transfused. Methods RhD-negative patients between 13 and 50 years who were transfused with ≥1 RhD-positive red blood cell (RBC) or whole blood units between January 1, 2000 and December 31, 2019 in a healthcare network were identified. Study patients had to have had at least one antibody detection test performed ≥14 days after the index RhD-positive transfusion and not receive RhIg. Patients were stratified into groups that received 1, 2, 3-5, 6-10, 11-20, and >20 RhD-positive transfusions and the RhD-alloimmunization rate was determined for each group. Results There were 335 patients included; 52/335 (15.5%) were females. Overall, there were 117/335 (34.9%, CI: 29.8%-40.3%) recipients who became RhD-alloimmunized. There was no significant dosage effect in the RhD-alloimmunization rates as the exposure to RhD-positive units increased from one RhD-positive unit to more than 20 RhD-positive units (p = .270 for non-parametric trend test). In an exploratory analysis, patients who received 100% of their RhD-positive transfusions within 72 h of the index transfusion had a significantly higher rate of RhD-alloimmunization compared to those who were transfused over a longer period of time (42.3% vs. 21.4%, respectively; p = .001). Conclusion These results suggest that there may not be an increased RhD-alloimmunization risk with transfusing multiple RhD-positive units after one RhD-positive unit has been transfused. These findings need confirmation in larger studies.

There are multiple known associations between the ABO and RhD blood groups and disease. However, no systematic population-based studies elucidating associations between a large number of disease states and blood group have been conducted. Using SCANDAT3-S, a comprehensive nationwide blood donation-transfusion database, we modelled outcomes for 1,217 disease categories including 70 million person-years of follow-up, accruing from 5.1 million unique individuals. We discovered 49 and 1 associations between a disease and ABO and RhD blood group, respectively, after adjustment for multiple testing. We identified new associations such as kidney stones and blood group B as compared to O. We also expanded previous knowledge on other associations such as pregnancy-induced hypertension and blood group A and AB as compared to O and RhD positive as compared to negative. Our findings generate strong further support for previously known associations, but also indicate new interesting relations.

BACKGROUND There are no contemporary published data on the frequency of the ABO and Rhesus D (RhD) blood groups in the Northern Territory (NT) of Australia, particularly for the large Aboriginal population. AIMS To establish the frequencies of ABO and RhD blood groups in the NT Aboriginal and non-Aboriginal populations in order to aid transfusion inventory management and clinical practice. METHODS Retrospective data were collected from 1 January 2012 to 31 December 2012. All patients with a blood group sample processed by the NT public hospital laboratories and a recorded ABO and RhD report were included. Results were analysed using Stata 14. RESULTS The Aboriginal and non-Aboriginal populations had significantly different ABO and RhD distributions (P

H-deficient phenotype individuals with absent or weak anti-H activity may remain undetected on standard routine blood grouping. We report a case of a 59-year-old-man presented with symptomatic anaemia secondary to upper gastrointestinal bleed with haemoglobin level of 68 g/L who required two units of packed red blood cells. He was previously grouped as O Rh D positive and had a history of uneventful multiple blood transfusions. His latest pre-transfusion investigations showed ABO discrepancy between forward and reverse blood grouping, pan-agglutination in both antibody screening and identification with negative direct Coombs test and autocontrol. Further testing including anti-H lectin test and saliva secretor study confirmed that the patient blood group was para-Bombay B RhD positive. This case highlights that the para-Bombay phenotype can be mistakenly labelled as "O" if further investigations are not performed.

Background Guidelines for laboratory assessment of fetomaternal haemorrhage (FMH) was published by the Australian and New Zealand Society of Blood Transfusion (ANZSBT) in 2002. However, data on adherence by practitioners and clinical outcomes are lacking. Aims The primary objective is to examine the follow-up testing and dosing of additional RhD immunoglobulin in RhD negative women who experienced large-volume FMH for whom additional intravenous RhD immunoglobulin was requested in Queensland, Australia. The secondary objectives are to examine the rate and risk factors of RhD alloimmunisation in these women. Materials and methods RhD negative women with FMH >6 mL for whom additional dose(s) of intravenous RhD immunoglobulin was requested through Australian Red Cross Lifeblood from February 2007 to February 2018 were identified. For each patient, the volume of FMH, methods and timing of FMH quantitation, dose of RhD immunoglobulin, maternal and cord blood groups were analysed against the corresponding antibody screen and identification. Results Following FMH >6 mL, only 15% and 11.5% of cases adhered to current ANZSBT guideline on follow-up testing and supplemental RhD immunoglobulin dosing respectively. Despite the provision of single supplemental RhD immunoglobulin at a ratio of 100 IU to 1 mL fetal red cells, the rate of RhD alloimmunisation in RhD negative women with RhD positive fetus or fetus of unknown RhD status following FMH >6 mL is at least 4%. Conclusions Poor compliance with guidelines for follow-up and management of large-volume FMH may contribute to increased risk of RhD alloimmunisation. Further analysis of data is warranted.

Background and objectives: Fetal RHD genotyping of cell-free maternal plasma DNA from RhD negative pregnant women can be used to guide targeted antenatal and postnatal anti-D prophylaxis for the prevention of RhD immunization. To assure the quality of clinical testing, we conducted an external quality assessment workshop with the participation of 31 laboratories. Materials and methods: Aliquots of pooled maternal plasma from gestational week 25 were sent to each laboratory. One sample was fetal RHD positive, and a second sample was fetal RHD negative. A reporting scheme was supplied for data collection, including questions regarding the methodological setup, results and clinical recommendations. The samples were tested blindly. Results: Different methodological approaches were used; 29 laboratories used qPCR and two laboratories used ddPCR, employing a total of eight different combinations of RHD exon targets. Fetal RHD genotyping was performed with no false-negative and no false-positive results. One inconclusive result was reported for the RHD positive sample. All clinical conclusions were satisfactory. Conclusion: This external quality assessment workshop demonstrates that despite the different approaches taken to perform the clinical assays, fetal RHD genotyping is a reliable laboratory assay to guide targeted use of Rh prophylaxis in a clinical setting. (Less)

Objectives Most literature on the frequencies of red blood cell (RBC) phenotypes are published in Europeans and Africans countries, with the frequencies in the Omani population unknown. We sought to determine the prevalence of RBC blood group phenotypes among Omani blood donors. Methods Blood group ABO, RhD type, and phenotyping were performed for 21 blood group antigens on enrolled blood donors. The following antigens were assessed serologically: Rh (C, c, E, e), Kell (K, k, Kpa, Kpb), Kidd (Jka, Jkb), Duffy (Fya, Fyb), Lewis (Lea, Leb), Lutheran (Lua, Lub), MNS (M, N, S, s), and P1. Results A total of 337 Omani blood donors were tested. The most common blood group was O+ (44.9%). Among the tested blood donors studied, 89.3% were RhD positive with R1r being the most common Rh phenotype. The k antigen was found at a frequency of 99.4%, while 4.5% of the blood donors studied were K+. The most common phenotype in the Duffy blood group system was Fy(a-b-), while the most common phenotypes in the Kidd and MNS blood group systems were Jk(a+b+) and M+N-S+s+ at 47.0% and 22.6%, respectively. The Le(a+) and Le(b+) antigens were found in 21.7% and 67.3% of the blood donors, respectively. One Jk(a-b-), one Le(a+b+), and two Lu(a-b-) individuals were identified. Conclusion This is the first study to examine the frequencies of RBC phenotypes among the Omani blood donors. The study's results show Duffy blood group frequencies that resemble what has been reported in the African population, and higher frequencies of the rare null phenotypes compared to European populations.

Introduction/Objective Preventing allomiunization from D-mismatched transfusions, i.e., transfusion RhD positive (RhD+) red blood cells (RBC) to an RhD negative (RhD–) individual, is not well established. We describe our hospital protocol and experiences managing RhD– young women who received emergency release D-mismatched transfusions. Methods/Case Report The pathologists evaluate all patients who received D-mismatched blood transfusions. The inclusion criteria for alloimmunization prophylaxis protocol include: RhD– females; The prophylaxis protocol depends on the RBC volume (RBCV) transfused. Patients who receive RBCV Results (if a Case Study enter NA) Since 2016, four eligible patients received RhIg prophylaxis protocol and none met the criteria for RBCX. All the patients started the prophylaxis protocol within 24 hours of transfusion and completed it within 72 hours. One patient developed post treatment hemolysis and significant drop in hemoglobin requiring blood transfusion. Passive anti-D post treatment was confirmed in three patients, and one had passive anti C. Three of the four patients had follow up antibody screens >6 months post treatment that were negative for RhD alloimmunization. Conclusion Our therapeutic plan, the first well established protocol, involves identifying eligible patients based on set criteria and protocols. Our experience demonstrates that this protocol is effective in reducing/preventing RhD alloimmunization.

Herein, we report a case of naturally occurring anti-Leb alloantibody identified in the plasma of a first time voluntary blood donor. The immunohematology workup was done on the pilot sample tubes collected during blood donation by the conventional tube technique and using ID-Micro Column System Glass Beads card (anti-IgG, C3d; Ortho-Clinical Diagnostics, Raritan, New Jersey, USA). Blood group of the donor was confirmed to be B RhD positive, and the alloantibody in his plasma was identified as anti-Leb, having clinically significant characteristics. Since in this particular case, anti-Leb was IgM and IgG in nature, it was clinically significant and can lead to hemolytic transfusion reaction, especially if such fresh frozen plasma unit is transfused to Leb negative patients.

The blood specimen of a 30-year-old male donor showing a discrepancy in cell and serum grouping was targeted for detailed study at the blood bank at tertiary care hospital in South Gujarat. Forward grouping showed group as "O" RhD positive and reverse grouping as group "A." Further testing confirmed that the individual's blood group was para-Bombay A (para-AH). Family members were screened, and younger brother was also identified as para-Bombay phenotype. The para-Bombay phenotype is very rare, and only a few cases have been reported from India. This blood group is characterized by the absence of ABH antigens on red blood cells (RBC's) with the presence of ABH substances in body secretions or by the weak expression of ABH antigens on RBC's with the absence or presence of substances in body secretions. This rare phenotype can be mislabeled as "O" if all detailed investigations are not performed.

Background Previous studies suggest that RhD positive heterozygotes express better health status than RhD positive homozygotes and especially RhD negative subjects. This also applies to pregnant women. According to the Trivers-Willard hypothesis, women in better physical condition should have more sons. Aim To test the hypothesis that RhD positive heterozygous mothers have a male-skewed sex ratio. Study design Cross-sectional study. The data was analysed using Chi-Square test for all women, separately for RhD positive and RhD negative women, and separately for primiparous and multiparous women. The effects of maternal weight as a continuous predictor and the RhD phenotype of newborn as a categorical predictor of newborn sex were evaluated by the generalized linear model (GLZ) separately for RhD positive and RhD negative women using binomial distribution and logit link function. Outcome measures Clinical records comprised maternal weight before pregnancy, number of previous deliveries, sex of the newborn, maternal RhD phenotype, and RhD phenotype of the newborn. Subjects We analysed data from 5655 women who gave birth between 2008 and 2012 in General University Hospital in Prague. Results Secondary sex ratio was significantly higher (P = 0.028) in RhD positive mothers who had RhD negative newborns, i.e., in heterozygotes (SR = 1.23), than in RhD positive mothers who had RhD positive newborns, i.e., in a mixed population of heterozygotes and homozygotes (SR = 1.00), especially in primiparous women (P = 0.013; SR = 1.37 and 0.99 resp.). Conclusion The sex ratio at birth was significantly higher in RhD positive mothers who had RhD negative newborns than in RhD positive mothers who had RhD positive newborns.

Background : The ABO is a blood group system that is responsible for most blood transfusion reactions, transplant rejections and determining some forensic cases. The ABO and Rhesus blood group systems have been shown to show variations in different part of the world and race. Aim : The study is to show the frequency of ABO and Rhesus blood groups amongst blood donors in Lagos, Nigeria and confirm Hardy-Weinberg equilibrium. Methods : This is a two-year retrospective study of all blood donors from the two major tertiary health institutions in Lagos State between July 2004 and June 2006. Data from the blood bank records were extracted and analysed using SPSS version 20. Hardy-Weinberg equation was used to confirm if the population is in equilibrium. Results : In all, 11,911 donors were analysed and showed A+ 20.4%, A- 0.97%, B+ 16.7%, B- 0.87%, AB+ 2.2%, AB- 0.17%, O+ 55.6%, O- 3.1% and RhD positive frequency is 95.6%. The allelic frequency in this study is O – 0.7631, A - 0.1303, B – 0.1066 and Rh – 0.7786. There is no significant difference between the blood group distributions from the two institutions. Conclusion : Blood group O was the commonest blood group seen followed by group A. This is at variance with other studies in Nigeria where blood group B was the second commonest. The population was also found to be in Hardy-Weinberg equilibrium. The study provides important and reliable genogeographical information that can advance the fields of blood transfusion, organ transplantation and forensic medicine in Nigeria. Key words : Blood group, ABO, Rhesus, allelic frequency, Hardy-Weinberg equilibrium, transfusion reactions

Cell-free DNA (cfDNA) RhD testing of maternal plasma has been implemented in Avon as a clinical service, so that normal rhesus D-negative pregnant women (about 15% of pregnant women) are only given antenatal anti-D if the fetus is RhD positive. As a result, only RhD-negative women carrying a RhD-positive baby are given antenatal anti-D, meaning that about 40% of healthy RhD-negative pregnant women need not be exposed to a blood product that is pooled from many donors. This also means health services can conserve the use of a costly product (requiring deliberate sensitisation of volunteers) that can be in short supply, for those who need it. The cfDNA RhD test is now available in NHS laboratories and this article proposes that maternity services should implement this approach across the country.

This and the next series of Best Practise Guidelines will revisit the main theories that attempt to explain the influences on the sex ratio at birth (M/F), which was similarly reviewed in this journal in 2015. The papers include a historical review of the classical theories and initial work pertaining to the study of M/F, an analysis of 88,875,750 live births in an attempt to quantify M/F, the effect of earthquakes and climate change and an attempt to approximate the primary sex ratio (at conception). Another theoretical paper provides several potential explanations for autism spectrum disorder that may be correlated with M/F. Yet paper tests the hypothesis that RhD positive heterozygous mothers have a male-skewed sex ratio. A final paper provides a systematic review of the factors that influences M/F. It is hoped that this set of papers will continue to provide stimulation and food for thought on this intriguing topic.

Background & objectives: The number of blood components required during a liver-transplant surgery is significant. It is challenging for blood transfusion services to provide the required RhD-negative red blood cells (RBCs) for recipients during the peri-operative period. This retrospective study presents safety data of transfusing RhD-positive RBCs in RhD-negative living donor liver-transplant (LDLT) recipients during the peri-operative period with six-month follow up for risk of developing alloantibodies. Methods: All RhD-negative patients who underwent LDLT and were transfused ABO-compatible but RhD-positive RBC units between January 2012 and May 2018 were included in the study. Twenty one RhD-negative patients who received a total of 167 RhD-positive RBCs peri-operatively were chosen for alloantibody screening. All the patients were started on triple immunosuppression drugs as per the standard hospital protocol. Blood grouping, cross-match and antibody screening were done by column agglutination technique. Results: Post-transplant antibody screen (weekly for 12 wk) was negative, and none of the patients developed anti-D alloantibodies till their last follow up (mean 21 months). Interpretation & conclusions: Our observations suggest that it may be safe to use RhD-positive RBCs peri-operatively in RhD-negative LDLT recipients with low risk of alloimmunization.

Transfusion medicine physicians have advocated for testing all RhD negative newly delivered mothers with RhD positive babies for the presence of fetal maternal hemorrhage since 1980. Despite this fact, guidelines written for obstetrical groups have not been entirely aligned with the testing algorithm put forth by transfusion medicine groups. This discrepancy led to policies within individual institutions that leave out certain patient groups from the screening protocols, which in turn places the patient at risk for sensitization to D. The literature and controversy surrounding this topic is quite dated; a 2017 update finally aligns the testing recommendations.

Testing for patient ABO type is important for two reasons. First, it allows the transfusion service to know which blood products are compatible with the circulating ABO isoagglutinins in the patient’s plasma. Second, it allows a switch in product support from “universal donor” products to ABO type-specific products. This is the most effective way to protect the community blood supply, particularly because more than 50% of patients will have a blood type other than O, and most patients are RhD positive. If a massive transfusion occurs before a sample is obtained for ABO type, it may be impossible to discern the patient’s native type. Further product support will entail risking the community supply of universal components in the effort to save the patient.

It is important to determine if a patient is RhD positive or negative for the purposes of transfusion and pregnancy. Occasionally, the RhD type is not able to be resulted or the result differs from results obtained in the past due to underlying genetic variation in the RHD gene. In these cases, it is important to do further testing using genotype testing to determine if the woman should be managed as RhD positive or RhD negative. If a woman of child-bearing potential makes anti-D antibody, her future pregnancies are at risk of hemolytic disease of the fetus and newborn (HDFN) if a fetus is RhD positive. RhIg is used to protect RhD negative women from this HDFN due to anti-D sensitization. These critical decisions are informed by clarifying the RhD type.

Background: Anti-D alloimmunization can occur when platelets from RhD-positive donors are transfused to RhD-negative patients, due to red blood cell residues in the platelet concentrates. Methods: Our objective was to analyze the anti-D alloimmunization rate in a selected group of women under 55 years of age diagnosed with acute leukemia over an 18-year period. We focused the analysis on RhD-negative patients who received RhD-positive platelet transfusions. Results: From January 1998 to October 2016, 382 women under 55 years were diagnosed with acute leukemia. A total of 56 patients were RhD-negative, and 48 (85.7%) received RhD-positive platelets. The median number of platelet concentrates transfused per patient was 23, and 48% of all platelet transfusions were RhD-positive. The 48 RhD-negative patients received a total of 949 RhD-positive platelet concentrates. Two patients developed anti-D: a 36-year-old woman with M3 acute myeloblastic leukemia and a 52-year-old patient with a secondary acute myeloblastic leukemia. Conclusion: We conclude that there is a need for agreement in the transfusion guidelines on the recommendation of anti-D alloimmunization prophylaxis. We suggest a possible benefit in favor of anti-D prophylaxis in childbearing women with acute leukemia.

Platelet transfusions have contributed to the revolutionary modern treatment of hypoproliferative thrombocytopenia. Despite the long-term application of platelet transfusion in therapeutics, all aspects of their optimal use (i.e., in cases of ABO and/or Rh (D incompatibility) have not been definitively determined yet. We reviewed the available data on transfusion practices and outcome in ABO and RhD incompatibility and platelet refractoriness due to anti-human leukocyte antigen (HLA) antibodies. Transfusion of platelets with major ABO-incompatibility is related to reduced posttransfusion platelet (PLT) count increments, compared to ABO-identical and minor, but still are equally effective in preventing clinical bleeding. ABO-minor incompatible transfusions pose the risk of an acute hemolytic reaction of the recipient that is not always related to high anti-A, B donor titers. ABO-identical PLT transfusion seems to be the most effective and safest therapeutic strategy. Exclusive ABO-identical platelet transfusion policy could be feasible, but alternative approaches could facilitate platelet inventory management. Transfusion of platelets from RhD positive donors to RhD negative patients is considered to be effective and safe though is associated with low rate of anti-D alloimmunization due to contaminating red blood cells. The prevention of D alloimmunization is recommended only for women of childbearing age. HLA alloimmunization is a major cause of platelet refractoriness. Managing patients with refractoriness with cross-matched or HLA-matched platelets is the current practice although data are still lacking for the efficacy of this practice in terms of clinical outcome. Leukoreduction contributes to the reduction of both HLA and anti-D alloimmunization.

Purpose of the study The aim of this study was to investigate RHD alleles among Tunisian blood donors with D-negative phenotype and positive for C and/or E antigen. Patients and methods A total of 100 D-negative and C/E+ samples were analyzed by RHD genotyping using an initial test for RHD exon 10. In case of a positive reaction, further molecular investigations including real time quantitative PCR, allele specific PCR and nucleotide sequencing were done to elucidate the RHD involved mechanisms. Results Seventy-five percent of the studied samples lacked the RHD gene. Twenty-three percent carried the hybrid RHD-CE-D alleles (16 RHD-CE(3-7)-D , 5 RHD-CE(4-7)-D , 1 RHD-CE(4-8)-D , 1 RHD-CE(3-8)-D ) and 2% were weak D (1 weak D type 1 and 1 weak D type 5). Conclusion Our study proved the high frequency of RHD gene among serologically D-negative samples, positive for C and/or E antigen. Thus achieving systematically RHCE phenotyping in all transfusion centers on the Tunisian territory and considering blood donated from D-negative C/E+ persons as D-positive will be recommended to reduce anti-D allo-immunization.

Starting in 2013, blood donors must be tested at least using: (1) one monoclonal anti-D and one anti-CDE (alternatively full RhCcEe phenotyping), and (2) all RhD negative donors must be tested for RHD exons 5 and 10 plus one further exonic, or intronic RHD specificity, according to the guidelines of the Blood Transfusion Service of the Swiss Red Cross (BTS SRC). In 2012 an adequate stock of RHD screened donors was built. Of all 25,370 RhD negative Swiss donors tested in 2012, 20,015 tested at BTS Berne and 5355 at BTS Zürich, showed 120 (0.47%) RHD positivity. Thirty-seven (0.15%) had to be redefined as RhD positive. Routine molecular RHD screening is reliable, rapid and cost-effective and provides safer RBC units in Switzerland.

The ABO and RHD systems represent the most immunogenic systems and the most sought after in blood transfusion. The objective of this work was to present new statistics of phenotypic prevalence of ABO and RHD systems in Morocco using a new sample. Our study was a retrospective, descriptive and epidemiological one carried out at the Blood Transfusion Center at the Avicenne Military Hospital in Marrakech on a sample of 10,000 donors collected between the year 2009 and the year 2017. The study of the expression Erythrocyte blood group antigens by the serological phenotyping technique was based on haemagglutination. Double determination was necessary to avoid the risk of grouping errors. This technique was simple and inexpensive, and today remains a gold standard for immunohematology. At the end of this study, the frequency of the antigens of the red blood cell systems ABO and RHD was as follows: ABO system: A (32.7%), B (16.33%), AB (5.26%), O (45.71%). RHD system: RHD positive (92.29%), RHD negative (7.71%). Our results were compared to other previous Moroccan and other foreign countries studies; this allowed us to locate hemotypologically the transfusion center of the Avicenne military hospital of Marrakech in the world. At the end of this study, we have concluded that our results were consistent with previous studies in Morocco. These results were identical to those found in the Mediterranean countries and showed that Morocco was in an intermediate position between the countries of Europe and those of Black Africa.

One of the basic rules of transfusion is to prevent alloimmunisation by highly immunogenic RhD antigen and not to transfuse RhD negative individuals with RhD positive blood. In some cases the expression of this antigen is so weak that it is undetectable in routine serological tests. The paper presents an algorithm for mass DNA testing with the purpose of identifying donors with low RhD expression. The screening is based on RHD gene detection (absent in RhD negative Caucasians) in DNA isolated from pools of 96 plasma samples from blood donors identified as RhD negative by the routine serological methods in Blood Transfusion Centers. Such procedure substantially reduces the costs. Plasma samples can be brought from the territory of the whole country, stored and accumulated for testing in one selected center. The cost would amount to approximately 25 PLN per donor. The test is performed once for each RhD negative individual. It is estimated that such persons will represent approximately 0.2% of RhD negative donors.

The frequency of red blood cell (RBC) alloimmunization in RhD positive pregnant women is not known in our population. We planned to determine its frequency and correlation with neonatal outcome. We included 1000 RhD positive pregnant women: 500 had 'normal pregnancy' (Group I) and another 500 had 'high risk pregnancy' (Group II). ABO and extended Rh phenotyping were done by tube technique, antibody screening and identification by gel technique. For alloimmunized women, the paternal and neonatal ABO and extended Rh typing were done. Neonatal direct antiglobulin test (DAT) was also done and their clinical outcome observed. The frequency of RBC alloimmunization was 0.7% (7/1000) and all these women were from group II (p = 0.015). The alloantibodies were anti-E (85.7%), anti-c (71.4%), anti-Cw (14.3%) and anti-S (14.3%). Also, 6 women had history of transfusion (p

The non-invasive technique to determine fetal RHD status opens the opportunity to change the antenatal screening and Rh-prophylaxis programs. During the period September 2009 to December 2011, we performed a study in the Stockholm area with approximately 27000 pregnancies per year. The study included routine cell free fetal DNA (cffDNA) RHD genotyping in early pregnancy followed by targeted RAADP in gestational week 29 to all RhD negative pregnant women carrying an RHD positive fetus. The new approach in our strategy, compared to previous studies, was that fetal RHD screening was done in early pregnancy at the first antenatal visit and based on a single-exon 4 assay. The implementation of this new screening program in a routine clinical setting is described. The final results of the study are still under analysis. The conclusion until now is that fetal RHD screening in early pregnancy is feasible and accurate with a high sensitivity and specificity, provided samples before gestational week eight were excluded.

To assess the impact of rheumatic heart disease (RHD) on child-reported health-related quality of life (HRQOL) in the context of a Ugandan school-based echocardiographic screening program. Echocardiography-based screening has emerged as a tool for the early detection of RHD, but little is known about its impact on those screened.Participants included 358 children from Gulu and 28 children from Kampala Uganda. The Pediatric Quality of Life Inventory Version 4.0 was used to assess HRQOL in 4 groups of children: Gulu prescreen, Gulu postscreen, Gulu previously linked to care, and Kampala previously linked to care. Children in the pre- and postscreen groups were selected from a single school before and after screening occurred and matched by age and sex. Children previously linked to care were recruited from previous screening studies.When the echocardiogram was normal, there was no difference in HRQOL in the prescreen and postscreen groups. In the postscreen group, identification of latent RHD resulted in lower physical (75.3 vs 68.3, P = .03) and emotional (71.7 vs 63.4, P .01) HRQOL, despite a lack of symptoms. The Kampala group had longer linkage to care (42 months vs 6 months, P .01) and demonstrated greater HRQOL scores compared with the Gulu-linked group (70.7 vs 77.8, P .01) and the combined Gulu cohort (77.8 vs 69.4, P = .02).Echocardiography-based screening for RHD does not diminish HRQOL in Ugandan children; rather, a diminished HRQOL score may be associated with being identified as RHD positive. Further investigation is needed to understand if longer linkage to care may ultimately normalize or improve HRQOL.

ABO and RHD blood grouping was carried out on 400 Saudi adult male subjects, 100 each from Sakaka, Domaht Al-Jandal, Al-Qurayat and Sweer cities of the Al-Jouf Province of the Saudi Arabia. Finger prick blood samples were tested for both the blood groups by routine slide method. In the total material studied here from the Al-Jouf Province, blood group O was found highest (0.628), followed by A (0.193), B (0.179) and AB (7.3%) while the percentage of RHD Positive (0.705)was greater than RHD negative(0.295). This study could have significant implications for the major blood banks in Al-Jouf area where certain blood groups are needed more than others in emergency conditions. In addition, the data generated would be helpful to the researchers to explore the factors responsible for the observed distribution patterns of the studied blood group systems.

Background: Determination of RHD zygosity is important for the prevention of haemolytic disease of foetus and neonate. There is no data from India regarding the prevalence of RHD genotypes. Objectives: We conducted this study to investigate RHD zygosity in phenotypically RhD positive (RhD+) Indians. We have also investigated the utility and concordance of two different genotyping techniques. Methods: Hundred serologically RhD+ Indians were genotyped at the RHD gene using polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) and polymerase chain reaction–sequence-specific primer (PCR–SSP) techniques. Results: Of the 100 RhD+ individuals, 26 (25%) were D heterozygous by both methods and 74 (71·2%) were D homozygous. There was no discordance in the results from the two techniques. Conclusion: At least 25% of RhD+ Indians are heterozygous at the RHD gene. Both the genotyping techniques were equally robust and their complete concordance indicates RHD deletion as the main mechanism underlying RhD negativity in Indians.

Non invasive fetal RhD genotyping, based on polymerase-chain-reaction (PCR), is an accurate and validated technique. It allows a reduction by one-third of anti-D immunoglobulin injections to prevent RhD allo-immunization. In case of maternal anti-D immunization, fetal RhD genotyping allows to focus on RhD positive fetuses only the biologic and sonographic follow-up. The wide use of this technique implies the validation and economic evaluation of a commercial RhD genotyping kit, ready for use in non specialized laboratories.

Rhesus-positive and Rhesus-negative persons differ in the presence-absence of highly immunogenic RhD protein on the erythrocyte membrane. The biological function of the RhD molecule is unknown. Its structure suggests that the molecular complex with RhD protein transports NH3 or CO2 molecules across the erythrocyte cell membrane. Some data indicate that RhD positive and RhD negative subjects differ in their tolerance to certain biological factors, including, Toxoplasma infection, aging and fatique. Present cross sectional study performed on 3,130 subjects) showed that Rhesus negative subjects differed in many indices of their health status, including incidences of many disorders. Rhesus negative subjects reported to have more frequent allergic, digestive, heart, hematological, immunity, mental health, and neurological problems. On the population level, a Rhesus-negativity-associated burden could be compensated for, for example, by the heterozygote advantage, but for Rhesus negative subjects this burden represents a serious problem.

Background: The D antigen is highly immunogenic, requiring only a small quantity of transfused red blood cells (RBCs) to cause alloimmunization in D- immunocompetent recipients. DEL was reported arousing alloimmunization to true Rh- patients. Molecular studies of the RHD gene have revealed that DEL individuals retain a grossly intact RHD gene or have a portion of RHD in their genomes. Avoiding immunization with clinically important antibodies is a primary objective in transfusion medicine. Methods: In order to determine whether pregnant DEL women carrying an RhD+ fetus are at risk of anti-D alloimmunization, 808 Rh- pregnant women with a history of gestations or parturitions who regularly visited hospitals for their prenatal anti-D screening and postpartum care from January 2011 to December 2012 were investigated. Samples were analyzed for DEL by PCR with specific primers, PCR-sequence-specific primers (PCR-SSP), reverse transcription-PCR (RT-PCR), PCR-restriction fragment length polymorphism (PCR-RFLP), and by gene sequencing to characterize different alleles. Results: Among the 808 Rh- pregnant women of our sample, 178 (22.0%) were typed as DEL; 168 DEL samples were confirmed to have the RHD (1,227 G>A) allele, 8 DEL samples were characterized by one base mutation of the RHD (3G >A) allele, and the remaining two DEL samples were determined to carry RHD-CE(4-9)-D or RHD-CE(2-5)-D. The observation of allo-anti-D in two prominent D epitope loss cases confirmed the partial nature of these DEL phenotypes. Conclusions: In conclusion, evidence is provided that different DEL genotypes code either for partial or complete D antigen expression. It is suggested that the use of RhD+ RBCs in complete D antigen DEL patients does not induce adverse reaction.

This work aims to assess the value of a generalized molecular RHD screening strategy which could replace routine serological screening of weak D by indirect antiglobulin test. Three independent studies were performed at the two Blood Transfusion Services Berne and Zurich. Donors investigated were 652 RhD negative, but RhC and/or RhE positive, 17,391 mainly Rhccee, and 8200 with normal RhCcEe phenotype distribution. In study I single samples, in studies II and III minipools of 24 and 20 donor samples were tested, respectively. Among 26,243 phenotypically RhD negative blood donors, 65 carriers of RHD alleles were identified. Thirty-one of them were redefined as RhD positive.

Background: Blood bank laboratories in developing countries with limited technical expertise can adapt the simple and rapid gel technology (GAT) to estimate fetomaternal hemorrhage (FMH). We present our experience of the utility of GAT in the detection and measurement of FMH. Methods: Stock solutions (n=17) of 7 serial dilutions containing appropriate concentrations of both fetal RhD positive and adult RhD negative cells were prepared. Both the Kleihauer-Betke technique (KBT) and GAT were performed on all samples. Results: The efficiency of GAT was more appreciated when the fetal cell contamination was ≥0.25%. A calibration curve was developed using a known serial concentration of fetal RhD positive and maternal RhD negative RBCs, which determines the volume of FMH by depicting the agglutination reaction against a particular anti-D dilution. Conclusions: Blood banks using gel technology for red cell serology can adapt GAT to screen FMH.

Serology for the presence of anti-D after RhD-incompatible platelet transfusions was performed in 24 RhD-negative patients with haematological disease and 59 RhD-negative patients with non-haematological disease. None of the patients were given prophylaxis with anti-D to prevent RhD immunization. Eight out of 59 (13.5%) non-haematology patients developed detectable anti-D, whereas 0 out of 24 (0%) of the haematology patients formed anti-D (P = 0.06). The risk of alloimmunization after RhD-incompatible platelet transfusions using platelet concentrates prepared by modern technical methods appears to be small in patients with haematological disease, but is significant in non-immunocompromised patients.