Rh Blood Research Articles

Blood group is a long-term cardiovascular risk factor after carotid endarterectomy

Background ABO blood group system has been clinically related to an increased incidence of cardiovascular diseases. Preliminary data relating Rhesus (Rh) factor and these outcomes also have been published. Our aim was to analyse the impact of blood group on the short and long-term outcomes after carotid endarterectomy (CEA). Materials and methods From 2012 to 2019, patients from a referral centre who underwent CEA for atherosclerotic carotid stenosis were prospectively followed. Our primary outcomes were long-term major adverse cardiovascular events (MACEs) and all-cause mortality. Secondary outcomes were perioperative complications and myocardial injury after non-cardiac surgery (MINS). Median follow-up was 50 months (interquartile range 21–69). Time-to-event analysis was used to determine the effect of ABO and Rh groups in long-term outcomes. Results One hundred and eighty-four patients were included, with a mean age of 70.1 ± 9.1 years. Eighteen (25.7%) patients with O type and 48 (42.1%) patients with non-O type presented coronary artery disease (odds ratio [OR]: 2.313, 5–95% confidence interval (CI) 1.245–4.297, p = .008). Patients Rh+ presented significantly more congestive heart failure, 23 (14.7%), p = .03. The incidence of MACE in the long-term was higher in non-O patients (adjusted hazard ratio: 2.034; CI: 1.032–4.010, p = .040). Rh− patients, presented a higher incidence of perioperative MINS. However, there was no statistically significant association with long-term risk of MACE. Conclusion The incidence of MACE in long-term analysis was higher in non-O blood type and 30-day MINS was significantly more common amongst Rh− patients. The benefit from a more complete preoperative cardiac study in these patients should be performed.

Frequency of Duffy, Kidd, Lewis, and Rh Blood Group Antigens and Phenotypes Among Donors in the Al-Ahsa Region, Saudi Arabia.

In Al-Ahsa, Saudi Arabia, the high consanguinity rates contribute to the prevalence of inherited hemoglobinopathies such as sickle cell disease and thalassemia, which frequently require blood transfusions. These transfusions carry the risk of alloimmunization, necessitating a precise blood component matching to mitigate health risks. Local antigen frequency data is vital for optimizing transfusion practices and enhancing the safety of these medical procedures for the Al-Ahsa population. This study investigated the distribution of Duffy, Kidd, Lewis, and Rh blood group antigens in 1,549 individuals from the region; comparing the frequencies with global data. Serological analyses revealed a high prevalence of the Fy(a+b-) and Jk(a+b+) phenotypes in the Duffy and Kidd blood groups, respectively, with Jk(a-b-) being notably scarce. The Lewis blood group exhibited a significant presence of Le(a-b+) and Le(a+b-) phenotypes, whereas Le(a+b+) was less common. In the Rh system, the D antigen was most prevalent, with other antigens following in descending order of frequency. The study underscores the regional variation in antigen frequencies, emphasizing the need for local blood banks to adapt their screening and matching practices to mitigate the risk of alloimmunization and enhance transfusion safety. These findings are pivotal for refining transfusion strategies and understanding the immunohematology landscape in Al-Ahsa.

Evaluation of blood group diversity and Rhesus factor with blood virus infection: A cohort of HCV, HBV, and COVID-19 Egyptian patients

Evaluation of blood group diversity and Rhesus factor with blood virus infection: A cohort of HCV, HBV, and COVID-19 Egyptian patients

Simultaneous high throughput genotyping of 36 blood group systems using NGS based on probe capture technology

Human blood group antigen has important biological functions, and transfusion of incompatible blood can cause alloimmunization and may lead to serious hemolytic reactions. Currently, serological methods are most commonly used in blood group typing. However, this technique has certain limitations and cannot fully meet the increasing demand for the identification of blood group antigens. This study describes a next-generation sequencing (NGS) technology platform based on exon and flanking region capture probes to detect full coding exon and flanking intron regions of the 36 blood group systems, providing a new high-throughput method for the identification of blood group antigens. The 871 capture probes were designed for the exon and flanking intron sequences of 36 blood group system genes, and synchronization analysis for 36 blood groups was developed. The library for NGS was tested using the MiSeq Sequencing Reagent Kit (v2, 300 cycles) by Illumina NovaSeq, and the data were analyzed by the CLC Genomics Workbench 21.0 software. A total of 199 blood specimens have been sequenced for the 41 genes from 36 blood groups. Among them, heterozygote genotypes were found in the ABO, Rh, MNS, Lewis, Duffy, Kidd, Diego, Gerbich, Dombrock, Globoside, JR, LAN, and Landsteiner-Wiene blood group systems. Only the homozygous genotype was found in the remaining 22 blood group systems. The obtained data in the NGS method shows a good correlation (99.98 %) with those of the polymerase chain reaction-sequence-based typing. An NGS technology platform for 36 blood group systems genotyping was successfully established, which has the characteristics of high accuracy, high throughput, and wide coverage.

The Distribution Patterns of Rhesus (Rh) Antigens.

The determination of one's blood group is dictated by the inheritance-based diversity in the presence or absence of RBC antigens on the surface. Extended Rhesus (Rh) antigens are the most clinically relevant antigens of blood group systems after the ABO blood group system in transfusion medicine. The aim of this study was to serologically assess the prevalence of extended Rh antigens across diverse blood group systems. A total of 2043 samples were tested for the ABO blood group and Rh typing with monoclonal antisera. The Rh phenotyping (C, c, E, e ) was performed on all the samples. The most frequently observed ABO blood group was O (36.5%), while AB (13.6%) was identified as the least prevalent. Positive Rh D antigen was found in 91.6% of tested samples, while 8.4% were Rh D-negative. The most frequently encountered antigen was e, followed by D, while the least prevalent was E. Establishing a Rh phenotype repository for blood donors and conducting Rh phenotype assessments as part of pretransfusion testing before initiating the initial blood transfusion for each patient could significantly lower the patients' incidence of alloimmunization.

Alloimmunization and autoimmunization among multitransfused thalassemia and sickle cell disease patients

Blood transfusion is the mainstay for management of hemoglobinopathies, including thalassemia and sickle cell disease (SCD). Apart from other transfusion related adverse effects, immunization is a significant complication, particularly in multitransfused recipients. Alloimmunization rates vary widely, both in thalassemia and SCD patients. Alloimmunization complicates the management in form of hemolytic transfusion reactions, difficulty in finding compatible units, delays in transfusion and increasing costs. Exact pathogenesis and prevention modality have not been elucidated. Apart from antigenic differences, immunomodulatory effects and inflammation also play a role in pathogenesis. Ethnic heterogeneity between donors and recipients predisposes to higher alloimmunization.Transfusion management of hemoglobinopathies across the globe is fragmented, with different levels of care. Guidelines propose red cell antigen profiling, transfusion of leucoreduced red cells, preferably matched for Rh and Kell antigens, over and above ABO-D matching. For alloimmunized patients, corresponding antibody negative red cells need to be transfused. However, patients from different backgrounds are variably transfused with whole blood/red cells, which may or may not be leukoreduced. Prophylactic antigen matching reduces the risk of alloimmunization, however, has limitations. RH variants may not be picked up by phenotyping alone. Moreover, the approach of prophylactic antigen matching is expensive, labour intensive, time consuming and may cause delays in transfusions. There is limited, low quality evidence on best practices for transfusion management of SCD and thalassemia. The review analyses the magnitude of problem, factors contributing and modalities for prevention and management of immunization.

Dual Maternal Alloimmunization by Antibodies of Rhesus and MNSs Blood Group System: Case Series and Approach to Work Up in a Resource Limited Set Up

Dual Maternal Alloimmunization by Antibodies of Rhesus and MNSs Blood Group System: Case Series and Approach to Work Up in a Resource Limited Set Up

A study of Some Factors Affecting the Prevalence of Renal Disease in Children

The current study was carried out in the period from 1 to 25 November 2023. It included sixty-two pediatric patients in the age range of (1-12) years and male and female children: twenty-six pediatric patients with chronic renal failure and thirty-six pediatric patients with nephrotic syndrome, who were outpatients and inpatients in the renal diseases unit and dialysis unit of both Al-Mansour Pediatric Teaching Hospital and Child's Central Teaching Hospital in Baghdad, Iraq. The control group consisted of twenty-six children in the same age range as the sick groups of males and females. Blood samples were collected from patients and controls. Then renal function was evaluated by applying the laboratory tests as urea and creatinine levels were measured in serum, besides blood group and Rh factor tests. Factors that may affect renal disease incidence and progress were recorded, such as socioeconomic status, residence (North, Middle, and South), and family history. The results explained the significant increase in both urea and creatinine concentrations (P<0.001) in serum compared with controls. The blood group and Rh factor had no significant differences among children of both sick groups. The entire affected factors had no significant association with renal disease incidence or progress in the current study. The age and gender of each child patient had no significant effect on the type of renal disease (at P value ≤ 0.01).

Absolute Lymphocyte Count and Outcomes of Multiple Myeloma Patients Treated with Idecabtagene Vicleucel: The US Myeloma Immunotherapy Consortium Real- World Experience

Idecabtagene vicleucel (ide-cel) has shown impressive efficacy in relapsed/refractory multiple myeloma (RRMM). This study aimed to investigate the impact of absolute lymphocyte count (ALC) on the survival outcomes of RRMM patients treated with standard of care (SOC) ide-cel. Data were collected retrospectively from 11 institutions in the U.S. Impact of ALC parameters including pre-apheresis (pre-A), pre-lymphodepletion (pre-LD), absolute and percent difference from pre-A to pre-LD on clinical outcomes after ide-cel were examined using survival analysis. A new ALC profile was created based on univariate analysis that comprises 3 groups: normal (≥1 × 109/L) pre-LD ALC (LDN), low (<1 × 109/L) pre-LD ALC (LDL) + percent reduction <37.5 (%RL), and LDL ALC + percent reduction ≥37.5 (%RH). A total of 214 SOC ide-cel recipients were included in this analysis. The median patient age was 64 years (interquartile range [IQR], 57 to 69 years), median number of prior therapies was 6 (IQR, 5 to 9), and median duration of follow-up was 5.4 months (IQR, 2.1 to 8.3 months). Most patients had both low pre-A ALC (75.3%) and pre-LD ALC (77.2%), and the reduction from pre-A to pre-LD (median, .65 to .55 × 109/L) was statistically significant. Univariate analysis showed that the LDL + %RH group had significantly worse progression-free survival (PFS) and overall survival (OS) compared to the LDL + %RL and LDN ALC groups (6-month PFS: 40% versus 67.6% and 60.9%; 6-month OS: 69.5% versus 87% and 94.3%). In multivariable analysis, after adjusting for age, performance status, cytogenetic risk, use of bridging therapy, and extramedullary disease, PFS did not maintain its statistical significance; however, OS remained significantly worse for LDL + %RH group compared to the LDN ALC group (hazard ratio [HR], 4.3; 95% confidence interval [CI], 1.1 to 17), but the difference between the LDL + %RH versus %RL groups was not statistically significant (HR, 1.7; 95% CI, .8 to 4.0). Our findings indicate that low pre-LD ALC with high %R from pre-A to pre-LD was associated with inferior survival outcomes, particularly OS, in patients who received SOC ide-cel.

When and why is red blood cell genotyping applicable in transfusion medicine: a systematic review of the literature.

This review aims to provide a better understanding of when and why red blood cell (RBC) genotyping is applicable in transfusion medicine. Articles published within the last 8 years in peer-reviewed journals were reviewed in a systematic manner. RBC genotyping has many applications in transfusion medicine including predicting a patient's antigen profile when serologic methods cannot be used, such as in a recently transfused patient, in the presence of autoantibody, or when serologic reagents are not available. RBC genotyping is used in prenatal care to determine zygosity and guide the administration of Rh immune globulin in pregnant women to prevent hemolytic disease of the fetus and newborn. In donor testing, RBC genotyping is used for resolving ABO/D discrepancies for better donor retention or for identifying donors negative for high-prevalence antigens to increase blood availability and compatibility for patients requiring rare blood. RBC genotyping is helpful to immunohematology reference laboratory staff performing complex antibody workups and is recommended for determining the antigen profiles of patients and prospective donors for accurate matching for C, E, and K in multiply transfused patients. Such testing is also used to determine patients or donors with variant alleles in the Rh blood group system. Information from this testing aides in complex antibody identification as well as sourcing rare allele-matched RBC units. While RBC genotyping is useful in transfusion medicine, there are limitations to its implementation in transfusion services, including test availability, turn-around time, and cost.

A patient with anti-f in India identified by extensive immunohematologic workup.

Anti-f is produced by exposure to the compound antigen ce (f) on red blood cells (RBCs), expressed when both c and e are present on the same protein (cis position). Although anti-f was discovered in 1953, there are few cases reported worldwide because the presence of anti-f is often masked by anti-c or anti-e and is not generally found as a single antibody. In the present case, anti-f was identified by using three-cell screening and 11-cell identification panels. The identification of anti-f was further supported by additional testing, including (1) Rh antigen typing; (2) antibody identification panels (enzyme-treated panel [ficin] and an in-house-constructed Rh panel); (3) look-back and phenotyping of donor RBC units, which were responsible for alloimmunization; and (4) molecular testing of the patient's RBCs.

ABO and Rh blood group distribution in ANA positive patients

Aims: Antinuclear antibody (ANA) positivity is a common finding in various autoimmune diseases, particularly those of rheumatologic origin. While ANA positivity alone may not be diagnostic, it serves as a valuable marker when supported by clinical findings, aiding in the diagnosis and prediction of autoimmune diseases. The relationship between blood group systems and various diseases has been an area of interest in medical research. In this study, we aimed to investigate the potential association between ABO blood group and ANA positivity, specifically examining whether the ABO blood group status poses a risk for autoimmune diseases in individuals with rheumatologic conditions. Methods: In this retrospective study, we analyzed the blood group data of 536 patients who tested positive for ANA and were receiving treatment for rheumatologic diseases. The blood group status of these individuals was determined using standard serologic techniques. The distribution of ABO and Rh factor blood groups among ANA-positive patients was compared with the blood group distribution in the general population. Statistical analysis was performed to assess any significant differences. Results: The analysis revealed that the distribution of ABO and Rh factor blood groups among ANA-positive individuals did not show a statistically significant difference compared to the general population. Specifically, there was no significant deviation in the prevalence of ABO blood groups (A, B, AB, O) or Rh factor (positive or negative) among ANA-positive patients compared to expected frequencies based on population data. Conclusion: Based on our findings, there appears to be no significant association between ABO blood group status and ANA positivity in patients with rheumatologic diseases. The distribution of ABO and Rh blood groups among ANA-positive individuals closely resembled that of the general population. Therefore, our study suggests that current blood group status may not serve as a predictive factor for autoimmune diseases in individuals who test positive for ANA. Further research is warranted to explore other potential factors contributing to autoimmune disease susceptibility.

Incidence and Risk Factors of Cholestasis in Newborns with Hemolytic Disease-A Case-Control Study.

Background/Objectives: One of the rare causes of cholestasis may be hemolytic disease of the fetus and newborn (HDFN). Methods: We retrospectively analyzed 88 medical records of HDFN newborns with cholestasis and 186 records of children with HDFN without cholestasis and conducted an observational, case-control, retrospective study. Results: Factors influencing the risk of cholestasis were lower gestational age at birth (36.83 ± 1.9 vs. 37.57 ± 1.8, p = 0.002), Rh or Kidd HDFN (80.7% vs. 53.2%), and the need for intrauterine transfusion (27.3 vs. 11.8%). The subjects had lower hemoglobin concentrations at birth (14.01 ± 3.8 vs. 16.39 ± 2.8 g/dL) and during whole hospital stay, higher cord blood total bilirubin concentration (4.26 ± 1.8 vs. 2.39 ± 1.4 mg/dL), higher maximum bilirubin concentration (15.27 ± 5.8 vs. 10.24 ± 3.4 mg/dL), and more frequent liver ultrasound abnormalities (19.9 vs. 6.3%). They also required more extended hospitalization due to higher rates of postnatal blood transfusion (33 vs. 3.8%), more frequent need for exchange transfusion (8.8% vs. 2.2%), more extended time and higher risk of phototherapy (94.3 vs. 59.1%), and higher usage of immunoglobulins (55.7 vs. 8.1%), parenteral nutrition (45.5 vs. 12.9%), and antibiotics (14.8 vs. 4.8%). Conclusions: The risk factors for cholestasis in children with HDFN are lower gestational age at delivery, Rh and Kidd serological type of HDFN, and the need for intrauterine transfusions.

Accuracy of RHC/c genotyping in Chinese Han population.

The RHCE gene plays an important role in the complex and polymorphic Rh blood group system. RHCE genotyping holds significant clinical and transfusion-related implications. The objective of this study was to evaluate the accuracy of RHC/c genotyping in the Chinese Han population. Blood samples were obtained from 653 Chinese Han blood donors. The serological RhD and RhCcEe types were determined using monoclonal antibodies. Subsequently, multiplex real-time polymerase chain reaction (PCR) analysis was performed for RHC and RHc genotyping. Additionally, exon 2 of RHCE and exon 1 of RHD were sequenced. The analysis in this study found 443 RhD-positive donors and 210 RhD-negative donors. Among the 653 total donors, discrepancies between the RHC genotyping results and the serological results were found in 37 individuals. Specifically, 6 false-positive RhC results in RhD-positive donors and 28 false-positive RhC results in RhD-negative donors were identified based on c.48C in RHCE exon 1. Additionally, 3 false-negative RhC results were observed in the RhD-positive donors due to a 109 bp insertion in RHCE intron 2. RHc typing demonstrated complete consistency between the real-time PCR and the serological results. In the Chinese Han population, RHC genotyping was reliable when consistent results were achieved by both c.48C-based and 109 bp insertion-based genotyping. Moreover, RHc genotyping based on c.203A and c.307C polymorphic loci demonstrated dependable performance.

RHC genotyping in Chinese Han population

BackgroundThe Rh blood group system is characterized by its complexity and polymorphism, encompassing 56 different antigens. Accurately predicting the presence of the C antigen using genotyping methods has been challenging. The objective of this study was to evaluate the accuracy of various genotyping methods for predicting the Rh C and to identify a suitable method for the Chinese Han population.MethodsIn total, 317 donors, consisting 223 D+ (including 20 with the Del phenotype) and 94 D− were randomly selected. For RHC genotyping, 48C and 109bp insertion were detected on the Real-time PCR platform and −292 substitution was analyzed via restriction fragment length polymorphism (RFLP). Moreover, the promoter region of the RHCE gene was sequenced to search for other nucleotide substitutions between RHC and RHc. Agreement between prediction methods was evaluated using the Kappa statistic, and comparisons between methods were conducted via the χ2 test.ResultsThe analysis revealed that the 48C allele, 109bp insertion, a specific pattern observed in RFLP results, and wild-type alleles of seven single nucleotide polymorphisms (SNPs) were in strong agreement with the Rh C, with Kappa coefficients exceeding 0.8. However, there were instances of false positives or false negatives (0.6% false negative rate for 109bp insertion and 5.4-8.2% false positive rates for other methods). The 109bp insertion method exhibited the highest accuracy in predicting the Rh C, at 99.4%, compared to other methods (P values≤0.001). Although no statistical differences were found among other methods for predicting Rh C (P values>0.05), the accuracies in descending order were 48C (94.6%) > rs586178 (92.7%) > rs4649082, rs2375313, rs2281179, rs2072933, rs2072932, and RFLP (92.4%) > rs2072931 (91.8%).ConclusionsNone of the methods examined can independently and accurately predict the Rh C. However, the 109bp insertion test demonstrated the highest accuracy for predicting the Rh C in the Chinese Han population. Utilizing the 109bp insertion test in combination with other methods may enhance the accuracy of Rh C prediction.

Resolution of RHCE Haplotype Ambiguities in Transfusion Settings.

Red blood cell (RBC) transfusion, limited by patient alloimmunization, demands accurate blood group typing. The Rh system requires specific attention due to the limitations of serological phenotyping methods. Although these have been compensated for by molecular biology solutions, some RhCE ambiguities remain unresolved. The RHCE mRNA length is compatible with full-length analysis and haplotype discrimination, but the RHCE mRNA analyses reported so far are based on reticulocyte isolation and molecular biology protocols that are fastidious to implement in a routine context. We aim to present the most efficient reticulocyte isolation method, combined with an RT-PCR sequencing protocol that embraces the phasing of all haplotype configurations and identification of any allele. Two protocols were tested for reticulocyte isolation based either on their size/density properties or on their specific antigenicity. We show that the reticulocyte sorting method by antigen specificity from EDTA blood samples collected up to 48 h before processing is the most efficient and that the combination of an RHCE-specific RT-PCR followed by RHCE allele-specific sequencing enables analysis of cDNA RHCE haplotypes. All samples analyzed show full concordance between RHCE phenotype and haplotype sequencing. Two samples from the immunohematology laboratory with ambiguous results were successfully analyzed and resolved, one of them displaying a novel RHCE allele (RHCE*03 c.340C>T).

Donor/recipient Rh-mismatched allogeneic hematopoietic stem cell transplantation: transfusion strategy and allo-immunization to red blood cell antigens.

In the case of donor/recipient rhesus (Rh)-incompatibility after allogeneic hematopoietic stem cell transplantation (alloHSCT), the transfusion policy in France is to transfuse red blood cells (RBC) in the donor's Rh phenotype from the day of transplantation, leading to a risk of allo-immunization, either of donor or recipient origin. In this single-center retrospective study, the incidence of donor/recipient Rh incompatibility was 7.1% over an 8-year period including 1012 alloHSCT. Six of 58 evaluable patients (10.3%) developed alloantibodies to RBC antigens within one year of alloHSCT. None of these allo-immunizations were directed against the donor-mismatched Rh antigens and none could have been prevented by the transfusion of recipient and donor Rh-compatible RBC units. None of these allo-immunizations led to immune-mediated hemolytic anemia. We observed a statistically significant higher incidence of chronic GVHD among patients with anti-RBC allo-immunization. In the context of donor/recipient Rh incompatibility, the transfusion of packed RBC units in the donor's Rh phenotype from the day of alloHSCT is feasible and not associated with a high risk of allo-immunization. The generalization of this strategy could be discussed even when donor and recipient Rh phenotypes could be respected, to allow the preservation of units of infrequent phenotypes for other indications.

Neonatal and Obstetrical Outcomes of Pregnancies Complicated by Alloimmunization.

Despite advances in the prevention of rhesus (Rh)(D) alloimmunization, alloantibodies to Rh(D) and non-Rh(D) red blood cell antigens continue to be detected in ∼4% of US pregnancies and can result in hemolytic disease of the fetus and newborn (HDFN). Recent reports on HDFN lack granularity and are unable to provide antibody-specific outcomes. The objective of this study was to calculate the frequency of alloimmunization in our large hospital system and summarize the outcomes based on antibody specificity, titer, and other clinical factors. We identified all births in a 6-year period after a positive red blood cell antibody screen result during pregnancy and summarized their characteristics and outcomes. A total of 707 neonates were born after a positive maternal antibody screen result (3.0/1000 live births). In 31 (4%), the positive screen result was due to rhesus immune globulin alone. Of the 676 neonates exposed to alloantibodies, the direct antibody test (DAT) result was positive, showing antigen-positivity and evidence of HDFN in 37% of those tested. Neonatal disease was most severe with DAT-positive anti-Rh antibodies (c, C, D, e, E). All neonatal red blood cell transfusions (15) and exchange transfusions (6) were due to anti-Rh alloimmunization. No neonates born to mothers with anti-M, anti-S, anti-Duffy, anti-Kidd A, or anti-Lewis required NICU admission for hyperbilirubinemia or transfusion. Alloimmunization to Rh-group antibodies continues to cause a majority of the severe HDFN cases in our hospital system. In neonates born to alloimmunized mothers, a positive DAT result revealing antigen-positivity is the best predictor of anemia and hyperbilirubinemia.

Distribution of ABO, Rh, and MNS blood groups from students in Walailak University, Thailand: A descriptive cross-sectional study

BackgroundThe presence or absence of blood group antigens can lead to alloimmunization, causing hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. The distribution of these antigens varies among different ethnic populations, making it essential to study their prevalence in specific regions. ObjectivesThis study aimed to investigate ABO, Rh, and MNS blood group antigens, phenotypes, and allele frequencies among university students in Southern Thailand. Materials and methodsBlood samples were collected and typed for blood group antigens using serological tests. Antigen, phenotype, and allele frequencies were calculated based on the observed phenotypes. ResultsThe most common ABO blood group was O (37.29%), followed by B (35.98%), A (19.47%), and AB (7.26%). Allele frequencies for ABO system were found to be 0.6107 for ABO*O, 0.2453 for ABO*B, and 0.1427 for ABO*A. Rh blood group distribution revealed a high prevalence of the D antigen (99.01%), followed by e (96.37%), C (95.05%), c (39.27%), and E (29.37%). The allele frequencies for D and d were 0.9005 and 0.0995, respectively. The MNS system showed M and N antigen frequencies of 85.81% and 67.66%, respectively. The most common phenotype was M+N+ (53.47%), followed by M+N− (32.34%) and M−N+ (14.19%). Mia antigen was present in 10.56% of our population. ConclusionsThis study provides an understanding of blood group distribution and gene frequency in our young population, which is crucial for blood management in community transfusion. Additionally, this knowledge holds significant value for population genetics studies.

Challenges in blood transfusion caused by anti-Hr0: A rare case of D-- Phenotype in Asia Abstract

Introduction D–Phenotype is linked to abnormal expression of RHCE gene. Consequently, individuals with this condition may develop antibodies against high-prevalence Rh antigens when exposed to a normal Rh phenotype, leading to challenges in blood matching.Case presentationA 90-year-old male was admitted to the hospital due to prostatitis and acute retention of urinary. Surgery was planned after evaluation by urologist. A request was made for 2 units of red blood cells (RBC). The result for unexpected antibody screening was positive, and the antibody was identified as anti-Hr0 alloantibody , a rare RHCE * CE-D (5) – CE was discovered by genetic testing. The patient has only one history of blood transfusion, which may result in the production of the anti-Hr0 antibody. Compatible blood donors for this patient were not found, even after extensive screening.ConclusionThis report records a rare case of a D-- phenotype individual who produced anti-Hr0 alloantibody. Subsequent analysis of RH gene sequencing revealed a genotype that has not been previously reported in Asia.