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Westhoff CM, Floch A. Blood group genotype matching for transfusion. Br J Haematol 2024. [PMID: 39104129 DOI: 10.1111/bjh.19664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Accepted: 07/11/2024] [Indexed: 08/07/2024]
Abstract
The last decade has seen significant growth in the application of DNA-based methods for extended antigen typing, and the use of gene sequencing to consider variation in blood group genes to guide clinical care. The challenge for the field now lies in educating professionals, expanding accessibility and standardizing the use of genotyping for routine patient care. Here we discuss applications of genotyping when transfusion is not straightforward including when compatibility cannot be demonstrated by routine methods, when Rh type is unclear, when allo- and auto-antibodies are encountered in stem cell and organ transplantation, for prenatal testing to determine maternal and foetal risk for complications, and Group A subtyping for kidney and platelet donors. We summarize current commercial testing resources and new approaches to testing including high-density arrays and targeted next-generation sequencing (NGS).
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Affiliation(s)
- Connie M Westhoff
- New York Blood Center Enterprises, National Center for Blood Group Genomics, New York, New York, USA
| | - Aline Floch
- Univ Paris Est Creteil, INSERM U955 Equipe Transfusion et Maladies du Globule Rouge, IMRB, Creteil, France
- Laboratoire de Biologie Medicale de Référence en Immuno-Hematologie Moleculaire, Etablissement Francais du Sang Ile-de-France, Creteil, France
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Ramsey G, Barriteau CM. Estimating the serological underrecognition of patients with weak or partial RHD variants. Transfusion 2024; 64:920-928. [PMID: 38634174 DOI: 10.1111/trf.17810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 03/05/2024] [Accepted: 03/14/2024] [Indexed: 04/19/2024]
Abstract
BACKGROUND For patients with weak or discrepant RhD RBC phenotypes, RHD genotyping is employed to determine need for RhD-negative management. However, many RHD variants are type D-negative or D-positive. Serological recognition rates (RRs) of weak and partial RHD variants are poorly characterized. STUDY DESIGN AND METHODS Four US studies employing RHD genotyping for weak or discrepant RhD phenotypes provided data for race/ethnicity-specific serological recognition. Three studies used microplate, and 1 used gel and tube; 2 had anti-D data. We obtained White and Hispanic/Latino allele frequencies (AFs) of weak D types 1, 2, and 3 single-nucleotide variants (SNVs) from the Genome Aggregation Database (gnomAD, v4.0.0) and devised Hardy-Weinberg-based formulas to correct for gnomAD's overcount of hemizygous RHD SNVs as homozygous. We compiled common partial RHD AF from genotyped cohorts of US Black or sickle cell disease subjects. From variant AF, we calculated hemizygous-plus-homozygous genetic prevalences. Serological prevalence: genetic prevalence ratios yielded serological RRs. RESULTS Overall RRs of weak D types 1-3 were 17% (95% confidence interval 12%-24%) in Whites and 12% (5%-27%) in Hispanics/Latinos. For eight partial RHD variants in Blacks, overall RR was 11% (8%-14%). However, DAR RR was 80% (38%-156%). Compared to microplate, gel-tube recognition was higher for type 2 and DAU5 and lower for type 4.0. Anti-D was present in 6% of recognized partial RHD cases, but only in 0.7% of estimated total genetic cases. DISCUSSION Based on AF, >80% of patients with weak or partial RHD variants were unrecognized serologically. Although overall anti-D rates were low, better detection of partial RHD variants is desirable.
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Affiliation(s)
- Glenn Ramsey
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Blood Bank, Northwestern Memorial Hospital, Chicago, Illinois, USA
| | - Christina M Barriteau
- Division of Hematology and Oncology, Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Blood Bank, Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
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Yin Q. DEL variants: review of molecular mechanisms, clinical consequences and molecular testing strategy. Funct Integr Genomics 2023; 23:318. [PMID: 37840046 DOI: 10.1007/s10142-023-01249-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 10/04/2023] [Accepted: 10/05/2023] [Indexed: 10/17/2023]
Abstract
Patients with DEL phenotype, a D variant with a low number of D antigens per red blood cell, are routinely typed as RhD-negative in serology testing and are detectable only by adsorption and elution techniques or molecular methods. DEL is of clinical importance worldwide, as indicated by its genotype-phenotype discrepancies among different populations and its potential to cause anti-D alloimmunization when DEL phenotype individuals are inadvertently managed as RhD-negative. This narrative review summarized the DEL alleles causing DEL phenotype and the underlying mechanisms. The clinical consequences and current molecular testing approach were discussed to manage the transfusion needs of patients and donors with DEL phenotype.
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Affiliation(s)
- Qinan Yin
- Henan Engineering Research Center of Digital Pathology and Artificial Intelligence Diagnosis, The First Affiliated Hospital of Henan University of Science and Technology, Luoyang, China.
- Precision Medicine Laboratory, School of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang, China.
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Owaidah AY, Yamani LZ. Misclassification of RhD variants among pregnant women: a systematic review. J Med Life 2023; 16:981-989. [PMID: 37900088 PMCID: PMC10600664 DOI: 10.25122/jml-2023-0004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 05/01/2023] [Indexed: 10/31/2023] Open
Abstract
The D antigen of the Rh blood group is considered clinically significant due to its ability to cause hemolytic transfusion reactions and hemolytic disease in the fetus and newborn. This systematic review discusses the prevalence of RhD variants among pregnant women and the importance of including RhD genotyping for prenatal testing to detect RhD variants and prevent anti-D alloimmunization. A comprehensive literature search was conducted using scientific search engines, including PubMed and MEDLINE databases, with the keywords 'anti-D alloimmunization', 'RhD variant', and 'pregnant women.' The review adhered to the PRISMA guidelines. Meta-analysis was performed using MedCalc version 20. A significance level of p≤0.05 was considered statistically significant for all two-tailed tests. The meta-analysis included four articles that met the inclusion criteria. The total prevalence of RhD positivity (RhD+) was 61% (95% CI:34%-85%). The prevalence ranged from 22% to 82%, indicating a high degree of heterogeneity between studies (I2=98.71%, p<0.0001). The overall prevalence of D variants was 15% (95% CI, 9%-23%) with a prevalence of 0.05% to 100%, showing a high degree of heterogeneity between studies (I2=99.89%, p<0.0001). Anti-D alloimmunization could occur in pregnant women with some types of RhD variants. All four studies focused on molecular testing of samples showing inconsistent or weak results with at least two anti-D antibodies using serological methods.
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Affiliation(s)
- Amani Yousef Owaidah
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Imam Abdulrahman bin Faisal University, Dammam, Saudi Arabia
| | - Lamya Zohair Yamani
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Imam Abdulrahman bin Faisal University, Dammam, Saudi Arabia
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Gammon RR, Conceicao M, Benitez N, Bright F, Counts K, Resto C, Rexer K. Comparison of RhD Typing Results by Serology and Molecular Methods. Lab Med 2023; 54:190-192. [PMID: 36124749 DOI: 10.1093/labmed/lmac097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVE Molecular testing determines D antigen status when abnormal serologic results are observed. Molecular testing is routinely batched, resulting in longer turnaround time for abnormal D status resolution. During the interim, obstetric patients with questionable/uninterpretable and weak D typing results by serology, per the immunohematology reference laboratory (IRL) policy, will receive RhD negative blood. This study aimed to determine whether serology results achieved a concordance. METHODS Six hospitals provided samples to the IRL (first IRL) for RhD status by DNA. De-identified samples were sent for serology RhD (second IRL). A concordance of ≥80% was acceptable. RESULTS Forty-nine samples were evaluated. Results were concordant (65.3% [32/49]) and discordant (34.7% [17/49]). This is significantly lower than clinically acceptable 80% (z = 2.57, P < .05). The turnaround-time was 3.0 hours for serology and 4.4 days for molecular evaluation. CONCLUSION Due to a low concordance, serology could not be used in place of molecular testing.
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Affiliation(s)
- Richard R Gammon
- Scientific, Medical, Technical Direction, OneBlood, Orlando, FL, USA
| | | | - Nancy Benitez
- Immunohematology Reference Laboratory, OneBlood, Fort Lauderdale, FL, USA
| | - Frieda Bright
- Centralized Transfusion Service, OneBlood, St Petersburg, FL, USA
| | - Kelley Counts
- Information Technology Administration, OneBlood, St Petersburg, FL, USA
| | - Claribel Resto
- Immunohematology Reference Laboratory, OneBlood, Fort Lauderdale, FL, USA
| | - Karl Rexer
- Information Technology Administration, OneBlood, St Petersburg, FL, USA.,Rexer Analytics, Winchester, MA, USA
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Rh Immune Globulin After the Transfusion of RhD-Positive Blood in a Patient with a Partial D Antigen. Obstet Gynecol 2022; 140:1052-1055. [PMID: 36357991 DOI: 10.1097/aog.0000000000004981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 08/25/2022] [Indexed: 11/13/2022]
Abstract
BACKGROUND Patients with a serologic weak D phenotype may demonstrate variable RhD expression. We present a case in which clinical management would have been simplified if RHD genotyping had been performed previously. CASE A 33-year-old patient, G11P4155, presented with an incomplete miscarriage and was transfused RhD-positive packed red blood cells after typing RhD-positive. The patient had been historically typed RhD-negative by a different testing methodology. Indirect antiglobulin testing was performed, which revealed a serologic weak D phenotype. The patient was given 9,600 micrograms of Rh immune globulin. Molecular testing revealed a partial D antigen, which was originally thought to be at risk for alloimmunization; however, this has since been disproven. CONCLUSION Although not yet universal practice, prenatal RHD genotyping for partial D antigen could have prevented the characterization of this patient as RhD-positive at the time of transfusion.
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Yin Q, Flegel WA. DEL in China: the D antigen among serologic RhD-negative individuals. J Transl Med 2021; 19:439. [PMID: 34670559 PMCID: PMC8527646 DOI: 10.1186/s12967-021-03116-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 09/21/2021] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Providing RhD-negative red cell transfusions is a challenge in East Asia, represented by China, Korea, and Japan, where the frequency of RhD-negative is the lowest in the world. FINDINGS Among 56 ethnic groups in China, the RhD-negative frequency in Han, the prevalent ethnicity, is 0.5% or less, similar to most other ethnic groups. The Uyghur ethnic group has the highest reported RhD-negative frequency of up to 4.7%, as compared to 13.9% in the US. However, an estimated 7.15 million RhD-negative people live in China. The RhD-negative phenotype typically results from a loss of the entire RHD gene, causing the lack of the RhD protein and D antigen. The DEL phenotype carries a low amount of the D antigen and types as RhD-negative in routine serology. The DEL prevalence in RhD-negative individuals averages 23.3% in the Han, 17% in the Hui and 2.4% in the Uyghur ethnicities. The Asian type DEL, also known as RHD*DEL1 and RHD:c.1227G > A allele, is by far the most prevalent among the 13 DEL alleles observed in China. CONCLUSION The purpose of this review is to summarize the data on DEL and to provide a basis for practical strategy decisions in managing patients and donors with DEL alleles in East Asia using molecular assays.
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Affiliation(s)
- Qinan Yin
- Laboratory Services Section, Department of Transfusion Medicine, NIH Clinical Center, National Institutes of Health, Bethesda, MD, 20892, USA
- Henan University of Science and Technology, Luoyang, Henan, China
| | - Willy Albert Flegel
- Laboratory Services Section, Department of Transfusion Medicine, NIH Clinical Center, National Institutes of Health, Bethesda, MD, 20892, USA.
- Huazhong University of Science and Technology, Wuhan, Hubei, China.
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Flegel WA. Proceed with care: the "uncommon" serologic weak D phenotypes. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2021; 19:272-276. [PMID: 34704554 PMCID: PMC8297679 DOI: 10.2450/2021.0147-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Willy Albert Flegel
- Department of Transfusion Medicine, NIH Clinical Center, National Institutes of Health, Bethesda, MD, United States of America
- Huazhong University of Science and Technology, Wuhan, Hubei, China
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Leiva-Torres GA, Chevrier MC, Constanzo-Yanez J, Lewin A, Lavoie J, Laganière J, Baillargeon N, Trépanier P, Robitaille N. High prevalence of weak D type 42 in a large-scale RHD genotyping program in the province of Quebec (Canada). Transfusion 2021; 61:2727-2735. [PMID: 34121202 DOI: 10.1111/trf.16518] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/26/2021] [Accepted: 04/28/2021] [Indexed: 01/05/2023]
Abstract
BACKGROUND The determination of the RhD phenotype is crucial to avoid alloimmunization, especially in childbearing women. Following the 2015 recommendation from the Work Group on RHD Genotyping, a large-scale RHD genotyping program was implemented in the province of Quebec (Canada) and offered to women ≤45 years old with a serological weak D or discordant results. Since weak D type 42 was previously shown to be prevalent among French Canadians, genotyping for that variant was also performed. Our aim was to report the prevalence of the weak D alleles in the province of Quebec. STUDY DESIGN AND METHODS A retrospective study of 2105 women with serological weak D referred to Hema-Quebec's immunohematology reference laboratory (IRL) between June 2016 and May 2020 was conducted. Results from the serological tests performed by the referring hospital were compiled and RHD were genotyped. RESULTS Most patients presented at least one serological result ≤2+ before being referred to Hema-Quebec. Weak D type 42 was the most prevalent variant, representing 17.5% (368/2105) of all individuals tested. Only 15.3% (323/2105) of patients were weak D type 1, 3.3% (69/2105) were type 2, and 8.6% (180/2105) were type 3. Weak D type 42 is highly expressed in regions with low immigration rate and known for their founder effect. CONCLUSION Our RHD genotyping program allowed for a better management of weak D. The province of Quebec presents a unique RHD genotype distribution. We confirmed that weak D type 42 is associated with a founder effect found in Caucasian French Canadians.
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Affiliation(s)
| | | | | | - Antoine Lewin
- Medical Affairs and Innovation, Hema-Quebec, Quebec, Quebec, Canada
| | - Josée Lavoie
- Medical Affairs and Innovation, Hema-Quebec, Quebec, Quebec, Canada
| | - Josée Laganière
- Medical Affairs and Innovation, Hema-Quebec, Quebec, Quebec, Canada
| | - Nadia Baillargeon
- Immunohematology Reference Laboratory, Hema-Quebec, Montreal, Quebec, Canada
| | | | - Nancy Robitaille
- Immunohematology Reference Laboratory, Hema-Quebec, Montreal, Quebec, Canada
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Liu C, Xue Y, Ouchari M, Yin Q. Transfusion management of a Chinese pregnant woman with RHD*DEL1 allele. Transfus Clin Biol 2021; 28:293-295. [PMID: 33991666 DOI: 10.1016/j.tracli.2021.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 04/25/2021] [Accepted: 05/04/2021] [Indexed: 11/26/2022]
Abstract
We report the case of a 33-year-old pregnant Chinese woman who typed as Rh-negative in routine serology. Two injections of RhIG were given and two Rh-negative red cell units were sourced and put aside then returned with a reduced shelf life. RHD*DEL1 allele was determined in this woman by RHD genotyping two month later after delivery occasionally. In this representative case, a pregnant woman with RHD*DEL1 allele can safely be managed as Rh-positive, avoiding the unnecessary procurement of Rh-negative red cells and payment for RhIG injections. We analyzed the cost benefit of using RHD genotyping to guide transfusion management on the Chinese pregnant woman in Beijing where the average salary level is top-ranked in China. Considering the healthcare condition in China, we recommend molecular analysis of serologic Rh-negative early in pregnancy before the Rh-negative transfusion and administration of RhIG become unnecessarily required.
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Affiliation(s)
- Chunyan Liu
- Department of Obstetrics & Gynecology, China-Japan Friendship Hospital, 100029 Beijing, China
| | - Yun Xue
- College of Medical Technology and Engineering, Henan University of Science and Technology, 471023 Luoyang, Henan, China
| | - Mouna Ouchari
- Department of Immunology, Columbia University, 10027 New York, USA
| | - Qinan Yin
- College of Medical Technology and Engineering, Henan University of Science and Technology, 471023 Luoyang, Henan, China.
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Yin Q, Srivastava K, Brust DG, Flegel WA. Transfusion support during childbirth for a woman with anti-U and the RHD*weak D type 4.0 allele. Immunohematology 2021; 37:1-4. [PMID: 33962485 DOI: 10.21307/immunohematology-2021-001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
D- red blood cells (RBCs), always in short supply, and Rh immune globulin (RhIG) are not needed for patient care if D+ RBCs can safely be transfused. According to a recent work group recommendation, patients with the RHD*weak D type 4.0 allele can be considered D+. We report an African American woman who presented for delivery at the end of the third trimester, at which time anti-U and a serologic weak D phenotype were recognized, requiring U-, D- RBC units. We obtained 3 U- RBC units, including 1 D- unit. Later, the RHD*weak D type 4.0 allele was determined by RHD genotyping, only 6 days before delivery. The patient had an uneventful vaginal delivery of a D+ baby. No transfusion was needed for mother or baby. In this case, a pregnant woman with the RHD*weak D type 4.0 allele can safely be managed as D+, relaxing the unnecessary D- restriction for the limited U- RBC supply. The procured U-, D- RBC unit was frozen with 14 days of shelf-life remaining. To conserve D- RBC units, not limited to U-, for patients with a definite need, we recommend molecular analysis of a serologic weak D phenotype before a transfusion becomes imminent. The best time to resolve a serologic weak D phenotype with RHD genotyping is early in a pregnancy. Immunohematology 2021;37:1-4 . D– red blood cells (RBCs), always in short supply, and Rh immune globulin (RhIG) are not needed for patient care if D+ RBCs can safely be transfused. According to a recent work group recommendation, patients with the RHD*weak D type 4.0 allele can be considered D+. We report an African American woman who presented for delivery at the end of the third trimester, at which time anti-U and a serologic weak D phenotype were recognized, requiring U–, D– RBC units. We obtained 3 U– RBC units, including 1 D– unit. Later, the RHD*weak D type 4.0 allele was determined by RHD genotyping, only 6 days before delivery. The patient had an uneventful vaginal delivery of a D+ baby. No transfusion was needed for mother or baby. In this case, a pregnant woman with the RHD*weak D type 4.0 allele can safely be managed as D+, relaxing the unnecessary D– restriction for the limited U– RBC supply. The procured U–, D– RBC unit was frozen with 14 days of shelf-life remaining. To conserve D– RBC units, not limited to U–, for patients with a definite need, we recommend molecular analysis of a serologic weak D phenotype before a transfusion becomes imminent. The best time to resolve a serologic weak D phenotype with RHD genotyping is early in a pregnancy. Immunohematology 2021;37:1–4 .
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Affiliation(s)
- Q Yin
- Department of Transfusion Medicine, NIH Clinical Center, National Institutes of Health , Bethesda, MD
| | - K Srivastava
- Laboratory Services Section, Department of Transfusion Medicine, NIH Clinical Center, National Institutes of Health , Bethesda, MD
| | - D G Brust
- Blood Banking and Transfusion Medicine, Department of Pathology, University of Texas Medical Branch , Galveston, TX
| | - W A Flegel
- Laboratory Services Section, Department of Transfusion Medicine, NIH Clinical Center, National Institutes of Health , 10 Center Drive, Bethesda, MD 20892
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Flegel WA. Méthode actuelle de détermination du facteur Rhésus en contexte de transfusion et de grossesse. CMAJ 2021; 193:E464-E465. [PMID: 33782178 PMCID: PMC8099161 DOI: 10.1503/cmaj.201212-f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Maryam DU, Mukhtar IG, Yusuf AA, Salisu AI. High prevalence of serological weak D phenotype and preponderance of weak D type 4.0.1. genetic variant in a Nigerian population: implications for transfusion practice in a resource-limited setting. Hematol Transfus Cell Ther 2021; 44:386-391. [PMID: 33744228 PMCID: PMC9477752 DOI: 10.1016/j.htct.2021.01.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 12/22/2020] [Accepted: 01/07/2021] [Indexed: 11/15/2022] Open
Abstract
Introduction Prevalence of RhD negative phenotype in Nigeria is low; this leads to scarcity of RhD negative red cells for transfusion. Serological and molecular genotyping of RhD negative individuals for weak D types could reduce this scarcity. The aim of this study was to determine the serological prevalence and molecular types of weak D phenotypes among blood donors and pregnant women in Kano, Nigeria. Methods A total of 4482 blood donors and pregnant women from three hospitals in Kano were recruited. An indirect antiglobulin test was used to determine weak D phenotypes. Molecular genotyping was performed on genomic DNA from whole blood amplified by polymerase chain reaction sequence-specific primers (PCR-SSP) with agarose gel electrophoresis. Results The mean age of the participants was 26.50 ± 5.79 years. The prevalence of the RhD negative phenotype was 4.2% (189/4482). Of the 189 RhD negative phenotypes, 20 (10.6%) were weak D positive. Molecular genotyping of the 20 Weak D positive phenotypes revealed 15 (75%) weak D type 4, of which 11 were due to the RHD*09.03 and RHD*DAR3 (T201R, F223V) polymorphisms and 4, due to RHD* 08.01 and RHD* DFV polymorphisms; 2 (10%) were due to the 602 C>G polymorphism, while the remaining 3 (15%) constituted partial D or other rare weak D types. Conclusion The prevalence of weak D positive phenotypes is high in this study; weak D type 4 is the most common RhD genetic variant. Routine serologic weak D testing of RhD negative blood and molecular genotyping should be encouraged in resource-limited settings.
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Affiliation(s)
| | | | - Aminu Abba Yusuf
- Faculty of Clinical Sciences, Bayero University, Kano, Nigeria; Aminu Kano Teaching Hospital, Kano, Nigeria
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Trépanier P, Chevrier MC, Constanzo Yanez J, Baillargeon N, St-Pierre C, Perreault J. Adapting to supply-and-demand emerging trends for antigen-negative red blood cell units. Transfusion 2021; 61:1489-1494. [PMID: 33515215 DOI: 10.1111/trf.16285] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 01/05/2021] [Accepted: 01/05/2021] [Indexed: 12/13/2022]
Abstract
BACKGROUND A global downtrend in blood usage has been observed by many countries, while the demand for antigen-negative red blood cell (RBC) units used in antigen-matched transfusions keeps increasing. The declining number of units collected exposes blood providers to a rapidly evolving supply challenge. METHODS This study was conducted retrospectively with use of internal data analysis to weigh Québec's situation regarding global and antigen-negative RBC demand, to measure the effects of community-directed recruitment and blood drives, and to evaluate the benefits of mass-scale RBC genotyping. RESULTS Our findings confirm a global RBC usage downtrend of over 20% total in the past 10 years with a steady antigen-negative usage and highlight the most requested negative antigen combinations. Our data also show our +39.5% progress regarding the number of Black donors recruited for antigen matching of patients with sickle cell disease in the past 3 years, as well as a constantly growing number of just-in-time blood collection for complex orders. Finally, our data summarize the efficiency of our mass-scale RBC genotyping efforts. CONCLUSION Altogether, this study confirms the demand trends for regular and antigen-negative RBC units in Québec and the efficient effects of our recruitment and typing strategies.
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Affiliation(s)
- Patrick Trépanier
- Héma-Québec, Medical Affairs and Innovation, Québec City, Québec, Canada
| | | | | | | | - Christine St-Pierre
- Héma-Québec, Customer Experience and Business Intelligence, St-Laurent, Québec, Canada
| | - Josée Perreault
- Héma-Québec, Medical Affairs and Innovation, Québec City, Québec, Canada
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Bingulac-Popović J, Babić I, Đogić V, Kundid R, Simović Medica J, Mišković B, Jukić I. Prenatal RHD genotyping in Croatia: preliminary results. Transfus Clin Biol 2020; 28:38-43. [PMID: 33227453 DOI: 10.1016/j.tracli.2020.10.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 10/23/2020] [Accepted: 10/30/2020] [Indexed: 11/17/2022]
Abstract
OBJECTIVES Croatian Institute of Transfusion Medicine (CITM) implemented non-invasive fetal RHD genotyping as a request for targeted antenatal anti-D prophylaxis. The diagnostic performance of in-house RT-PCR method for fetal RHD genotyping and preliminary results are analyzed. MATERIALS AND METHODS Evaluation included results of RHD genotyping for 205 RhD negative pregnant women, 12-36th week of gestation, whose samples were received in period between 2015 and 2020. QIAsymphony SP DSP Virus Midi Kit was used for cffDNA extraction on QIAsymphony SP platform (Qiagen, Germany). Fragments of RHD exons 7 and 10 and later exon 5 were RT-PCR amplified. As internal controls, amplification of SRY gene or RASSF1A fragment and β-actin genes digested with BsTUI were used. RESULTS We identified 70.72% (145/205) positive and 28.78% (59/205) negative fetal RHD genotypes. We had one inconclusive result (0.50%) due to the interference of maternal DNA with variant genotype RHD*09.02.00/01/*01N.01. When compared to newborns RhD phenotypes, no false negative and three false positive results (3/199, 1.50%) were observed. The test yielded 100% sensitivity and 95.08% specificity, while diagnostic accuracy was 98.48%. We were able to determine one case of fetal variant genotype RHD*04.04/*01N.01 inherited from the father. The negative and positive predictive test values were 100% and 97.86%, respectively. CONCLUSION Automated cffDNA extraction and RT-PCR amplification of fetal RHD exons 5,7,10 and fragments of SRY, RASSF1A genes represents highly reliable system for determining fetal RHD status which enables targeted antenatal anti-D prophylaxis. To obtain high specificity of cffDNA extraction, strict and thoroughly cleaning procedures are required.
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Affiliation(s)
- J Bingulac-Popović
- Department of Molecular Diagnostics, Croatian Institute of Transfusion Medicine, Petrova 3, 10000 Zagreb, Croatia.
| | - I Babić
- Department of Molecular Diagnostics, Croatian Institute of Transfusion Medicine, Petrova 3, 10000 Zagreb, Croatia.
| | - V Đogić
- Department of Molecular Diagnostics, Croatian Institute of Transfusion Medicine, Petrova 3, 10000 Zagreb, Croatia.
| | - R Kundid
- Department of Molecular Diagnostics, Croatian Institute of Transfusion Medicine, Petrova 3, 10000 Zagreb, Croatia.
| | - J Simović Medica
- Department of Transfusion Medicine, General Hospital Pula, Santoriova 24a, 52100 Pula, Croatia.
| | - B Mišković
- Department of Obstetrics and Gynecology, Clinical Hospital "Holy Spirit", 64 Holy Spirit, 10000 Zagreb, Croatia.
| | - I Jukić
- Medical Department, Croatian Institute of Transfusion Medicine, Petrova 3, 10000 Zagreb, Croatia; Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Cara Hadrijana 10/E, 31000 Osijek, Croatia.
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17
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Flegel WA, Denomme GA, Queenan JT, Johnson ST, Keller MA, Westhoff CM, Katz LM, Delaney M, Vassallo RR, Simon CD, Sandler SG. It's time to phase out "serologic weak D phenotype" and resolve D types with RHD genotyping including weak D type 4. Transfusion 2020; 60:855-859. [PMID: 32163599 DOI: 10.1111/trf.15741] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 01/21/2020] [Accepted: 02/15/2020] [Indexed: 12/21/2022]
Affiliation(s)
- Willy A Flegel
- Department of Pathology and Laboratory Medicine, MedStar Georgetown University Hospital, Washington, DC, USA.,Department of Transfusion Medicine, NIH Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | | | - John T Queenan
- Department of Obstetrics and Gynecology, MedStar Georgetown University Hospital, Washington, DC, USA
| | | | - Margaret A Keller
- National Molecular Laboratory, American Red Cross Biomedical Services, Philadelphia, Pennsylvania, USA
| | - Connie M Westhoff
- Laboratory of Immunohematology and Genomics, New York Blood Center Enterprises, New York, New York, USA
| | - Louis M Katz
- Mississippi Valley Regional Blood Center, Davenport, Iowa, USA
| | | | | | - Clayton D Simon
- Defense Health Agency, Armed Services Blood Program Office, Falls Church, Virginia, USA
| | - S Gerald Sandler
- Department of Pathology and Laboratory Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
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18
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Londero D, Monge J, Hellberg A. A multi-centre study on the performance of the molecular genotyping platform ID RHD XT for resolving serological weak RhD phenotype in routine clinical practice. Vox Sang 2020; 115:241-248. [PMID: 31912520 DOI: 10.1111/vox.12886] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 10/17/2019] [Accepted: 12/17/2019] [Indexed: 12/28/2022]
Abstract
BACKGROUND AND OBJECTIVES There is concern regarding the lack of prevention of unnecessary transfusion of RhD negative red cells and unnecessary administration of Rh immunoglobulin (RhIG) to pregnant women. In this study, performance of ID RHD XT, a genotyping assay for identification of six RHD allelic variants and human platelet antigens HPA-1a/1b was assessed. MATERIALS AND METHODS Whole blood samples presenting weak, discrepant or inconclusive D phenotype results were genotyped with ID RHD XT and compared to reference molecular tests. Candidacy for RhIG prophylaxis was determined by analysing samples from pregnant women. Hands-on time to complete the procedures was measured. RESULTS Overall, 167 samples were tested (55 donors, 56 patients, 52 pregnant women and four newborns). Agreement between ID RHD XT and the reference method was 100% (51% weak D type 1, 2 or 3; 35·5% weak D Types 1, 2 or 3 not detected; 4% RHD deletion; 1% RHD*Pseudogene; 1% RHD*DIIIa-CE(3-7)-D; and 4% no amplification variant detected for RHD genotype; and 64% HPA-1a/a; 30% HPA-1a/b; and 3% HPA-1b/b for HPA-1 genotype). Call rate was 98·2%. ID RHD XT identified 40% of the pregnant women that would not have required RhIG prophylaxis. Overall hands-on time was 25-45 min to process a batch of 24 samples, and four hours for total assay time. CONCLUSION ID RHD XT yielded reproducible results for RHD typing in serologically weak D phenotype individuals. ID RHD XT was proven useful for the correct management of patients with RhD serological discrepancies and the rational use of RhIG in pregnancy.
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Affiliation(s)
- Donatella Londero
- Immunohematology Laboratory, Azienda Sanitaria Universitaria Friuli Centrale (ASU FC), Udine, Italy
| | - Jorge Monge
- Immunohematology Laboratory, Basque Centre for Blood Transfusion & Human Tissues, Galdakao, Spain.,Cell Therapy, Stem Cells and Tissues Group, Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Asa Hellberg
- Nordic Reference Laboratory for Genomic Blood Group Typing, Lund University Hospital, Lund, Sweden
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19
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Abstract
Red blood cell (RBC) antigen phenotyping is an essential component of transfusion compatibility testing. Serology has been the gold standard method, but its low throughput and risk of diagnostic interference in certain situations limits its applicability. Genotyping is useful for phenotyping in these cases, providing a high-throughput and reliable alternative to serology. Genotyping is indicated in several hematology and oncology patient populations. Because genotyping requires a complex testing environment and bears an additional risk of genotype-phenotype discrepancy, its use is currently limited, but it serves as a useful adjunct and may eventually supplant serology as a new gold standard.
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Affiliation(s)
- Ronald Jackups
- Department of Pathology & Immunology, Washington University School of Medicine, 660 South Euclid Avenue #8118, St Louis, MO 63110, USA.
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20
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Zonneveld R, Kanhai HHH, Javadi A, Veldhuisen B, Brand A, Zijlmans WCWR, van der Schoot CE, Schonewille H. Frequency and characterization of RHD variants in serologically D- Surinamese pregnant women and D- newborns. Transfusion 2019; 59:2672-2677. [PMID: 31183885 DOI: 10.1111/trf.15394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 04/25/2019] [Accepted: 05/12/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND Numerous RHD variant genes affect the expression of D on the red blood cell surface. In Suriname, 4.3% of pregnant women were D-, ranging from virtually zero to 7% among ethnic groups. Characterization of RHD variants, which are associated with a variable potential to induce anti-D, is of practical clinical importance especially in case of limited access to preventive measures. Here we report on the occurrence of RHD variant genes in Surinamese serologically D- pregnant women and their D- newborns from different ethnic groups. STUDY DESIGN AND METHODS The RheSuN study is a cross-sectional cohort study in D- pregnant women and their newborns, who visited hospitals in Paramaribo, Suriname, during routine pregnancy care. The presence of RHD variants was investigated using quantitative polymerase chain reaction targeting RHD Exons 5 and 7 and RH-multiplex ligation-dependent probe amplification. RESULTS Seven RHD variant genes were detected in 35 of 84 women and four RHD variant genes in 15 of 36 newborns. The RHD*03 N.01 and RHD*08 N.01 variants represented 87% of a total of 62 variant genes. Variants were comparably frequent among ethnicities. In four cases genotyping would have changed anti-D prophylaxis policy: one woman with a RHD*01EL.01 variant, not associated with anti-D formation and three D- newborns with RHD*09.01 and RHD*09.03.01 variants, potentially capable of inducing anti-D. CONCLUSION RHD variants at risk for anti-D are common among serologic D- individuals from African descent in Suriname. While genotyping D- women has limited added value, it may be considered in newborns from D- women.
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Affiliation(s)
- Rens Zonneveld
- Scientific Research Center Suriname, Academic Hospital Paramaribo, Paramaribo, Suriname.,Department of Pediatrics, Academic Hospital Paramaribo, Paramaribo, Suriname
| | - Humphrey H H Kanhai
- Faculty of Medical Sciences, Anton the Kom University of Suriname, Paramaribo, Suriname.,Department of Obstetrics, Leiden University Medical Center, Leiden, The Netherlands
| | - Ahmad Javadi
- Department of Experimental Immunohematology, Sanquin Research, Amsterdam, The Netherlands
| | - Barbera Veldhuisen
- Department of Experimental Immunohematology, Sanquin Research, Amsterdam, The Netherlands
| | - Anneke Brand
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Wilco C W R Zijlmans
- Scientific Research Center Suriname, Academic Hospital Paramaribo, Paramaribo, Suriname.,Faculty of Medical Sciences, Anton the Kom University of Suriname, Paramaribo, Suriname.,Department of Pediatrics, Diakonessen Hospital, Paramaribo, Suriname
| | - C Ellen van der Schoot
- Department of Experimental Immunohematology, Sanquin Research, Amsterdam, The Netherlands
| | - Henk Schonewille
- Department of Experimental Immunohematology, Sanquin Research, Amsterdam, The Netherlands
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21
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Abstract
Genomics is affecting all areas of medicine. In transfusion medicine, DNA-based genotyping is being used as an alternative to serological antibody-based methods to determine blood groups for matching donor to recipient. Most antigenic polymorphisms are due to single nucleotide polymorphism changes in the respective genes, and DNA arrays that target these changes have been validated by comparison with antibody-based typing. Importantly, the ability to test for antigens for which there are no serologic reagents is a major medical advance to identify antibodies and find compatible donor units, and can be life-saving. This review summarizes the evolving use and applications of genotyping for red cell and platelet blood group antigens affecting several areas of medicine. These include prenatal medicine for evaluating risk of fetal or neonatal disease and candidates for Rh-immune globulin; transplantation for bone marrow donor selection and transfusion support for highly alloimmunized patients and for confirmation of A2 status of kidney donors; hematology for comprehensive typing for patients with anemia requiring chronic transfusion; and oncology for patients receiving monoclonal antibody therapies that interfere with pretransfusion testing. A genomics approach allows, for the first time, the ability to routinely select donor units antigen matched to recipients for more than ABO/RhD to reduce complications. Of relevance, the growth of whole-genome sequencing in chronic disease and for general health will provide patients' comprehensive extended blood group profile as part of their medical record to be used to inform selection of the optimal transfusion therapy.
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22
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Delaney M. Haemolytic disease of the fetus and newborn: advancements in precision and prevention. ACTA ACUST UNITED AC 2018. [DOI: 10.1111/voxs.12479] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Meghan Delaney
- Pathology & Laboratory Medicine Division; Children's National Health System; Washington DC USA
- Department of Pediatrics & Pathology; George Washington University; Washington DC USA
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23
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Molano A, Apraiz I, España P, Azkarate M, Vesga MÁ, Rubia M, Piedrabuena M, Puente F, Veldhuisen B, Schoot E, Tejedor D, López M. Performance evaluation study of ID RHD XT, a new genotyping assay for the detection of high‐prevalence RhD negative and weak D types. Vox Sang 2018; 113:694-700. [DOI: 10.1111/vox.12701] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 06/27/2018] [Accepted: 07/16/2018] [Indexed: 12/16/2022]
Affiliation(s)
- Araitz Molano
- R&D Area Progenika Biopharma A Grifols Company Derio Spain
| | - Izaskun Apraiz
- R&D Area Progenika Biopharma A Grifols Company Derio Spain
| | | | - Maria Azkarate
- Centro Vasco de Transfusiones y Tejidos Humanos Galdakao Spain
| | | | | | | | | | | | - Ellen Schoot
- Sanquin Blood Supply Research Amsterdam the Netherlands
| | - Diego Tejedor
- R&D Area Progenika Biopharma A Grifols Company Derio Spain
| | - Mónica López
- R&D Area Progenika Biopharma A Grifols Company Derio Spain
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24
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Webb J, Delaney M. Red Blood Cell Alloimmunization in the Pregnant Patient. Transfus Med Rev 2018; 32:213-219. [PMID: 30097223 DOI: 10.1016/j.tmrv.2018.07.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 05/22/2018] [Accepted: 07/05/2018] [Indexed: 12/13/2022]
Abstract
Alloimmunization to red blood cell (RBC) antigens represents a challenge for physicians caring for women of child bearing potential. Exposure to non-self RBC antigens may occur during transfusion or pregnancy leading to the development of antibodies. If a subsequent fetus bears that antigen, maternal antibodies may attack the fetal red blood cells causing red cell destruction and clinically significant hemolytic disease of the fetus and newborn (HDFN). In the most severe cases, HDFN may result in intrauterine fetal demise due to high output cardiac failure, effusions and ascites, known as "hydrops fetalis". This article reviews strategies for management and prevention of RBC alloimmunization in women of child bearing potential.
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Affiliation(s)
- Jennifer Webb
- Children's National Health System, Washington, D.C., USA; The George Washington University, Departments of Pediatrics & Pathology, Washington, DC, USA.
| | - Meghan Delaney
- Children's National Health System, Washington, D.C., USA; The George Washington University, Departments of Pediatrics & Pathology, Washington, DC, USA
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25
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Laget L, Izard C, Durieux-Roussel E, Gouvitsos J, Dettori I, Chiaroni J, Ferrera-Tourenc V. Relevance and costs of RHD genotyping in women with a weak D phenotype. Transfus Clin Biol 2018; 26:27-31. [PMID: 29866395 DOI: 10.1016/j.tracli.2018.05.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 05/11/2018] [Indexed: 10/14/2022]
Abstract
OBJECTIVES For pregnant women, the serologic test results of D antigen will determine the frequency of RBC antibody detection as well as the indication for RhIG prophylaxis. RHD genotyping is the only method that may provide clear guidance on prophylaxis for women with a weak D phenotype. This analysis evaluated the economical implications of using RHD genotyping to guide RhIG prophylaxis among pregnant women with a serological weak D phenotype. METHODS We compared the costs of 2 strategies in a cohort of 273 women with weak D phenotype. In the first strategy, we did not perform genotyping and all women with weak D phenotypes were treated as if they were D-, thus considered to be a risk of RhD alloimmunization. These women all received the prophylactic follow up. In the second strategy, RHD genotyping was performed on all women with a serologic weak D phenotype. Then, the follow-up will be determined by phenotype deduced from genotype. RESULTS On the studied cohort, the additional expense occurred by genotyping is 26,536 €. RHD Genotyping has highlighted 162 weak D Type 1, 2 3, that could safely be managed as D+ and 111 partial D to consider as D-. By comparing the 2 strategies, the savings generated by genotyping the patients of our cohort are € 12,046 for the follow up of one pregnancy. Knowing that in France, a woman has on average 2 pregnancies and that the genotyping is carried out only once, the savings generated for the following pregnancies would be € 38,581. CONCLUSIONS Performing RHD genotyping for pregnant women with a weak D phenotype enables to clearly identify weak D type 1, 2 or 3 from the other variants at risk of alloimmunization. This analysis generates savings in terms of follow-up schedule of pregnant women and RhIG prophylaxis. It also allows saving of D- products for patient with a weak D type 1, 2 or 3 in case of a transfusion need.
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Affiliation(s)
- L Laget
- Établissement français du sang Provence Alpes Côte d'Azur Corse, laboratoire d'immuno-hématologie, site Marseille, Marseille, France.
| | - C Izard
- Établissement français du sang Provence Alpes Côte d'Azur Corse, laboratoire d'immuno-hématologie, site Marseille, Marseille, France
| | - E Durieux-Roussel
- Établissement français du sang Provence Alpes Côte d'Azur Corse, laboratoire d'immuno-hématologie, site Marseille, Marseille, France
| | - J Gouvitsos
- Établissement français du sang Provence Alpes Côte d'Azur Corse, laboratoire d'immuno-hématologie, site Marseille, Marseille, France
| | - I Dettori
- Établissement français du sang Provence Alpes Côte d'Azur Corse, laboratoire d'immuno-hématologie, site Marseille, Marseille, France
| | - J Chiaroni
- Établissement français du sang Provence Alpes Côte d'Azur Corse, laboratoire d'immuno-hématologie, site Marseille, Marseille, France
| | - V Ferrera-Tourenc
- Établissement français du sang Provence Alpes Côte d'Azur Corse, laboratoire d'immuno-hématologie, site Marseille, Marseille, France
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26
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Clausen FB. Lessons learned from the implementation of non-invasive fetalRHDscreening. Expert Rev Mol Diagn 2018; 18:423-431. [DOI: 10.1080/14737159.2018.1461562] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Frederik Banch Clausen
- Laboratory of Blood Genetics, Department of Clinical Immunology, Copenhagen University Hospital, Copenhagen, Denmark
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27
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Red blood cell alloimmunization: new findings at the bench and new recommendations for the bedside. Curr Opin Hematol 2017; 23:543-549. [PMID: 27454234 DOI: 10.1097/moh.0000000000000277] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
PURPOSE OF REVIEW To summarize recent discoveries from clinical studies and animal models that contribute to understanding the alloimmune response to non-ABO blood group antigens. RECENT FINDINGS Several studies have confirmed high rates of alloimmunization among patients requiring chronic red blood cell (RBC) transfusion. Moreover, 'triggers' for alloantibody development in the transfusion setting have been identified, with a number of investigations linking recipient inflammation to a higher likelihood of alloimmunization. Additional associations between human leukocyte antigen expression and CD4 T-cell markers in 'responder' or 'nonresponder' humans have been revealed. Recent animal studies have described novel mechanistic properties by which the alloimmune response is governed, including the critical role played by dendritic cells in transfusion-associated alloimmunization. New light has also been shed on the properties of alloantibodies developed as a result of pregnancy, as well as mechanisms through which such alloimmunization may be prevented. SUMMARY Many of the clinical/biological factors that contribute to the RBC alloimmune response have been further elucidated. This knowledge will be applied to identify individuals most likely to mount an immune response to RBC antigens, such that appropriate resources and strategies for preventing alloimmunization (or mitigating its harmful effects) can be implemented.
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28
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Flegel WA, Gottschall JL, Denomme GA. Integration of red cell genotyping into the blood supply chain: a population-based study. LANCET HAEMATOLOGY 2017. [PMID: 26207259 DOI: 10.1016/s2352-3026(15)00090-3] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND When problems with compatibility arise, transfusion services often use time-consuming serological tests to identify antigen-negative red cell units for safe transfusion. New methods have made red cell genotyping possible for all clinically relevant blood group antigens. We did mass-scale genotyping of donor blood and provided hospitals with access to a large red cell database to meet the demand for antigen-negative red cell units beyond ABO and Rh blood typing. METHODS We established a red cell genotype database at the BloodCenter of Wisconsin on July 17, 2010. All self-declared African American, Asian, Hispanic, and Native American blood donors were eligible irrespective of their ABO and Rh type or history of donation. Additionally, blood donors who were groups O, A, and B, irrespective of their Rh phenotype, were eligible for inclusion only if they had a history of at least three donations in the previous 3 years, with one donation in the previous 12 months at the BloodCenter of Wisconsin. We did red cell genotyping with a nanofluidic microarray system, using 32 single nucleotide polymorphisms to predict 42 blood group antigens. An additional 14 antigens were identified via serological phenotype. We monitored the ability of the red cell genotype database to meet demand for compatible blood during 3 years. In addition to the central database at the BloodCenter of Wisconsin, we gave seven hospitals online access to a web-based antigen query portal on May 1, 2013, to help them to locate antigen-negative red cell units in their own inventories. FINDINGS We analysed genotype data for 43,066 blood donors. Requests were filled for 5661 (99.8%) of 5672 patient encounters in which antigen-negative red cell units were needed. Red cell genotyping met the demand for antigen-negative blood in 5339 (94.1%) of 5672 patient encounters, and the remaining 333 (5.9%) requests were filled by use of serological data. Using the 42 antigens represented in our red cell genotype database, we were able to fill 14,357 (94.8%) of 15,140 requests for antigen-negative red cell units from hospitals served by the BloodCenter of Wisconsin. In the pilot phase, the seven hospitals identified 71 units from 52 antigen-negative red cell unit requests. INTERPRETATION Red cell genotyping has the potential to transform the way antigen-negative red cell units are provided. An antigen query portal could reduce the need for transportation of blood and serological screening. If this wealth of genotype data can be made easily accessible online, it will help with the supply of affordable antigen-negative red cell units to ensure patient safety. FUNDING BloodCenter of Wisconsin Diagnostic Laboratories Strategic Initiative and the NIH Clinical Center Intramural Research Program.
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29
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Sandler SG, Chen L, Flegel WA. Serological weak D phenotypes: a review and guidance for interpreting the RhD blood type using the RHD genotype. Br J Haematol 2017; 179:10-19. [PMID: 28508413 PMCID: PMC5612847 DOI: 10.1111/bjh.14757] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Approximately 0·2-1% of routine RhD blood typings result in a "serological weak D phenotype." For more than 50 years, serological weak D phenotypes have been managed by policies to protect RhD-negative women of child-bearing potential from exposure to weak D antigens. Typically, blood donors with a serological weak D phenotype have been managed as RhD-positive, in contrast to transfusion recipients and pregnant women, who have been managed as RhD-negative. Most serological weak D phenotypes in Caucasians express molecularly defined weak D types 1, 2 or 3 and can be managed safely as RhD-positive, eliminating unnecessary injections of Rh immune globulin and conserving limited supplies of RhD-negative RBCs. If laboratories in the UK, Ireland and other European countries validated the use of potent anti-D reagents to result in weak D types 1, 2 and 3 typing initially as RhD-positive, such laboratory results would not require further testing. When serological weak D phenotypes are detected, laboratories should complete RhD testing by determining RHD genotypes (internally or by referral). Individuals with a serological weak D phenotype should be managed as RhD-positive or RhD-negative, according to their RHD genotype.
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Affiliation(s)
- S. Gerald Sandler
- Department of Pathology and Laboratory Medicine, MedStar Georgetown University Hospital, Washington, DC
| | - Leonard Chen
- Department of Pathology and Laboratory Medicine, MedStar Georgetown University Hospital, Washington, DC
| | - Willy A. Flegel
- Department of Transfusion Medicine, NIH Clinical Center, National Institutes of Health, Bethesda, MD, United States
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30
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Lukacevic Krstic J, Dajak S, Bingulac-Popovic J, Dogic V, Mratinovic-Mikulandra J. Anti-D reagents should be chosen accordingly to the prevalence of D variants in the obstetric population. J Clin Lab Anal 2017. [PMID: 28649781 DOI: 10.1002/jcla.22285] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Resolving ambiguous results of D antigen typing is crucial for appropriate and rational administration of anti-D immunoprophylaxis and transfusion practice in obstetric population. The aim of the study was to establish selection criteria of anti-D reagents for our population. METHODS A total of 12 689 samples from primiparous women in Split-Dalmatia County, Croatia, were typed for RhD antigen during the period of 5 years. Ambiguous results were submitted to additional serologic investigation and genotyping. RHD genotyping was performed by commercial genotyping kits (Ready Gene weak D ® and Ready gene CDE, Inno-Train, Kronberg, Germany). Relative frequencies and accompanying 95% confidence intervals were used to estimate the prevalence of variants. RESULTS The prevalence of D variants was 0.42% (95% CI 0.31; 0.53). The most common partial D variant was D Va (RHD*05.05), with the prevalence of 0.08% (95% CI 0.03; 0.13). All weak D variants were weak D types 1, 2 and 3 (RHD*weak D type 1, RHD*weak D type 2, RHD*weak D type 3). Weak D samples were distinguishable from partial D in routine typing due to the difference in reactivity of partial D samples with clones D7B8 and RUM-1. Cell line RUM-1 gives weak or negative reactions with partial DVa category. CONCLUSION The most common partial D variant in our population is DVa. It is recommended to use cell lines which do not strongly agglutinate DVa variant in routine RhD typing. The appropriate choice of reagents will enable the serology methods to recognize the cases in which RHD genotyping is required.
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Affiliation(s)
| | - Slavica Dajak
- Department of Transfusion Medicine, Split University Hospital Center, Split, Croatia
| | - Jasna Bingulac-Popovic
- Department of Molecular Diagnostics, Croatian Institute of Transfusion Medicine, Zagreb, Croatia
| | - Vesna Dogic
- Department of Molecular Diagnostics, Croatian Institute of Transfusion Medicine, Zagreb, Croatia
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31
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Quantock KM, Lopez GH, Hyland CA, Liew YW, Flower RL, Niemann FJ, Joyce A. Anti-D in a mother, hemizygous for the variantRHD*DNBgene, associated with hemolytic disease of the fetus and newborn. Transfusion 2017. [DOI: 10.1111/trf.14156] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Kelli M. Quantock
- Blood Bank Division; Department of Pathology, Mater Health; South Brisbane Queensland Australia
| | - Genghis H. Lopez
- Research and Development, Clinical Services and Research Division, Australian Red Cross Blood Service; Kelvin Grove Queensland Australia
| | - Catherine A. Hyland
- Research and Development, Clinical Services and Research Division, Australian Red Cross Blood Service; Kelvin Grove Queensland Australia
| | - Yew-Wah Liew
- Red Cell Reference Laboratory, Clinical Services and Research Division; Australian Red Cross Blood Service; Kelvin Grove Queensland Australia
| | - Robert L. Flower
- Research and Development, Clinical Services and Research Division, Australian Red Cross Blood Service; Kelvin Grove Queensland Australia
| | - Frans J. Niemann
- Blood Bank Division; Department of Pathology, Mater Health; South Brisbane Queensland Australia
| | - Arthur Joyce
- Blood Bank Division; Department of Pathology, Mater Health; South Brisbane Queensland Australia
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32
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Bub CB, Aravechia MG, Costa TH, Kutner JM, Castilho L. RHD alleles among pregnant women with serologic discrepant weak D phenotypes from a multiethnic population and risk of alloimmunization. J Clin Lab Anal 2017; 32. [PMID: 28374955 DOI: 10.1002/jcla.22221] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 02/23/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND A considerable number of RHD alleles responsible for weak and partial D phenotypes have been identified. Serologic determination of these phenotypes is often doubtful and makes genetic analysis of RHD gene highly desirable in transfusion recipients and pregnant women. We analyzed the RHD gene in a cohort of pregnant women with doubtful D phenotypes. METHODS RHD genotyping was performed on 104 cases with D typing discrepancies or with history of serologic weak D phenotype. Laboratory-developed DNA tests, RHD BeadChip (Bioarray Solutions, Immucor), and sequencing were used to identify the RHD alleles. RESULTS Molecular analyses showed 23 of 104 (22%) pregnant women were RHD*weak D types 1, 2, or 3 and not at risk for anti-D. Fifty-one (49%) were RHD*weak partial 4.0, 6 RHD*weak D type 38 (6%), 1 RHD*weak D type 45 (1%), 1 RHD*weak D type 67 (1%), and potentially at risk for being alloimmunized and making anti-D. Partial D was identified in 22 of 104 (21%) patients and definitively at risk for anti-D. DISCUSSION Appropriate classification of RhD phenotypes is recommended for correct indication of RhIG in pregnant women. However, the serologic distinction between RhD-negative and RhD-positive phenotypes is a difficult task in the case of D variants due to the variations in serologic testing. Our results show a great variability in RHD variant alleles in pregnant women from this population of high admixture. According to these results, 78% of these obstetric patients are at risk for anti-D and candidates for RhIG.
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Affiliation(s)
- Carolina Bonet Bub
- Hemotherapy and Cellular Therapy Department, Hospital Israelita Albert Einstein, Sao Paulo, Brazil
| | - Maria Giselda Aravechia
- Hemotherapy and Cellular Therapy Department, Hospital Israelita Albert Einstein, Sao Paulo, Brazil
| | - Thiago Henrique Costa
- Hemotherapy and Cellular Therapy Department, Hospital Israelita Albert Einstein, Sao Paulo, Brazil
| | - José Mauro Kutner
- Hemotherapy and Cellular Therapy Department, Hospital Israelita Albert Einstein, Sao Paulo, Brazil
| | - Lilian Castilho
- Hemotherapy and Cellular Therapy Department, Hospital Israelita Albert Einstein, Sao Paulo, Brazil.,Hemocentro Unicamp, Campinas, Brazil
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McGowan EC, Lopez GH, Knauth CM, Liew YW, Condon JA, Ramadi L, Parsons K, Turner EM, Flower RL, Hyland CA. Diverse and novelRHDvariants in Australian blood donors with a weak D phenotype: implication for transfusion management. Vox Sang 2017; 112:279-287. [DOI: 10.1111/vox.12488] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 12/21/2016] [Accepted: 12/21/2016] [Indexed: 12/13/2022]
Affiliation(s)
- E. C. McGowan
- Clinical Services and Research; Australian Red Cross Blood Service; Kelvin Grove QLD Australia
| | - G. H. Lopez
- Clinical Services and Research; Australian Red Cross Blood Service; Kelvin Grove QLD Australia
| | - C. M. Knauth
- Clinical Services and Research; Australian Red Cross Blood Service; Kelvin Grove QLD Australia
- School of Biomedical Sciences; Faculty of Health; Queensland University of Technology; Brisbane QLD Australia
| | - Y.-W. Liew
- Red Cell Reference Laboratory; Australian Red Cross Blood Service; Kelvin Grove QLD Australia
| | - J. A. Condon
- Red Cell Reference Laboratory; Australian Red Cross Blood Service; West Melbourne Vic. Australia
| | - L. Ramadi
- Red Cell Reference Laboratory; Australian Red Cross Blood Service; West Melbourne Vic. Australia
| | - K. Parsons
- Red Cell Reference Laboratory; Australian Red Cross Blood Service; Alexandria NSW Australia
| | - E. M. Turner
- Red Cell Reference Laboratory; Australian Red Cross Blood Service; Kelvin Grove QLD Australia
| | - R. L. Flower
- Clinical Services and Research; Australian Red Cross Blood Service; Kelvin Grove QLD Australia
| | - C. A. Hyland
- Clinical Services and Research; Australian Red Cross Blood Service; Kelvin Grove QLD Australia
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Lukacevic Krstic J, Dajak S, Bingulac-Popovic J, Dogic V, Mratinovic-Mikulandra J. Anti-D Antibodies in Pregnant D Variant Antigen Carriers Initially Typed as RhD. Transfus Med Hemother 2016; 43:419-424. [PMID: 27994529 DOI: 10.1159/000446816] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/22/2016] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND To evaluate the incidence, the consequences, and the prevention strategy of anti-D alloimmunizations of D variant carriers in the obstetric population of Split-Dalmatia County, Croatia. METHODS RhD immunization events were evaluated retrospectively for the period between 1993 and 2012. Women were tested for RhD antigen and irregular antibodies. Those with anti-D antibody who were not serologically D- were genotyped for RHD. They were evaluated for their obstetric and transfusion history and their titer of anti-D. The neonates were evaluated for RhD status, direct antiglobulin test (DAT), hemoglobin and bilirubin levels, transfusion therapy as well as phototherapy and outcome. RESULTS Out of 104,884 live births 102,982 women were tested for RhD antigen. Anti-D immunization occurred in 184 women which accounts for 0.9% of individuals at risk of anti-D formation. 181 cases occurred in women serologically typed as D-. Three women were partial D carriers (DVa n = 2, DNB n = 1), initially typed RhD+, and recognized as D variant carriers after the immunization occurred. Anti-D titer varied from 1:1 to 1:16. Six children were RhD+, four had positive DAT, and two underwent phototherapy. CONCLUSION Anti-D immunization occurred in pregnant partial D carriers (DVa, DNB). RhD+ children had serologic markers of hemolytic disease of the fetus and newborn (HDFN), with no cases of severe HDFN.
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Affiliation(s)
- Jelena Lukacevic Krstic
- Department of Transfusion Medicine, Split University Hospital Center, Split, Croatia, Zagreb, Croatia
| | - Slavica Dajak
- Department of Transfusion Medicine, Split University Hospital Center, Split, Croatia, Zagreb, Croatia
| | | | - Vesna Dogic
- Croatian Institute of Transfusion Medicine, Zagreb, Croatia
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Hemolytic Disease of the Fetus and Newborn: Modern Practice and Future Investigations. Transfus Med Rev 2016; 30:159-64. [DOI: 10.1016/j.tmrv.2016.05.008] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Accepted: 05/23/2016] [Indexed: 11/20/2022]
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36
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Molecular immunohaematology round table discussions at the AABB Annual Meeting, Anaheim 2015. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2016; 14:557-565. [PMID: 27483480 DOI: 10.2450/2016.0063-16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 05/17/2016] [Indexed: 12/16/2022]
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Fichou Y, Mariez M, Le Maréchal C, Férec C. The experience of extended blood group genotyping by next-generation sequencing (NGS): investigation of patients with sickle-cell disease. Vox Sang 2016; 111:418-424. [PMID: 27442304 DOI: 10.1111/vox.12432] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 06/04/2016] [Accepted: 06/06/2016] [Indexed: 12/12/2022]
Abstract
BACKGROUND Patients suffering from haemoglobinopathies may be treated by red blood cell (RBC) transfusion on a regular basis and then exposed to multiple antigens with a recurrent, potential risk of alloimmunization routinely prevented by extended RBC antigen cross-matching. While time-consuming and labour-intensive serological analyses are the gold standard for RBC typing, genotyping by current high-throughput molecular tools, including next-generation sequencing (NGS), appears to offer a potent alternative. STUDY DESIGN AND METHODS The potential of extended blood group genotyping (EBGG) by NGS of 17 genes involved in 14 blood group systems was evaluated in a cohort of 48 patients with sickle-cell disease. Sample preparation and sequencing were simplified and automated for future routine implementation. RESULTS Sequencing data were obtained for all DNA samples with two different sequencing machines. Prediction of phenotypes could be made in 12 blood group systems and partially in two other blood group systems (Rh and MNS). Importantly, predicted phenotypes in the MNS (S/s), Duffy, Kidd and Kell systems matched well with serological data (98·9%), when available. Unreferenced alleles in the ACHE and ART4 genes, respectively, involved in the Yt and Dombrock blood groups, were identified, then contributing to extend the current knowledge of blood group molecular genetics. CONCLUSIONS Overall, we consider that our strategy for NGS-based EBGG, assisted by a simple method for genotyping exons 1 and 2 of the pairs of homologous genes (i.e. RHD/RHCE and GYPA/GYPB), as well as the future support of potent bioinformatics tools, may be implemented for routine diagnosis in specific populations.
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Affiliation(s)
- Y Fichou
- Etablissement Français du Sang (EFS) - Région Bretagne, Brest, France.,Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1078, Brest, France
| | - M Mariez
- Etablissement Français du Sang (EFS) - Région Bretagne, Brest, France.,Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1078, Brest, France
| | - C Le Maréchal
- Etablissement Français du Sang (EFS) - Région Bretagne, Brest, France.,Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1078, Brest, France.,Laboratoire de Génétique Moléculaire et d'Histocompatibilité, Centre Hospitalier Régional Universitaire (CHRU), Hôpital Morvan, Brest, France.,Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale (UBO), Brest, France
| | - C Férec
- Etablissement Français du Sang (EFS) - Région Bretagne, Brest, France.,Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1078, Brest, France.,Laboratoire de Génétique Moléculaire et d'Histocompatibilité, Centre Hospitalier Régional Universitaire (CHRU), Hôpital Morvan, Brest, France.,Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale (UBO), Brest, France
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Red cell alloimmunisation: incidence and prevention. LANCET HAEMATOLOGY 2016; 3:e260-1. [PMID: 27264033 DOI: 10.1016/s2352-3026(16)30043-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 05/05/2016] [Indexed: 11/20/2022]
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Sandler SG. Blood group genotyping: faster and more reliable identification of rare blood for transfusion. Lancet Haematol 2015; 2:e270-1. [PMID: 26688381 DOI: 10.1016/s2352-3026(15)00093-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 05/05/2015] [Indexed: 11/16/2022]
Affiliation(s)
- S Gerald Sandler
- Department of Laboratory Medicine, MedStar Georgetown University Hospital, Washington, DC 20007, USA
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40
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Delaney M. What is the value of a blood type? Transfusion 2015; 55:2057-9. [PMID: 26372913 DOI: 10.1111/trf.13227] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 06/08/2015] [Indexed: 11/27/2022]
Affiliation(s)
- Meghan Delaney
- Bloodworks Northwest, Seattle, WA.,Department of Laboratory Medicine & Pediatrics, University of Washington, Seattle, WA
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A model for integrating molecular-based testing in transfusion services. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2015; 14:566-572. [PMID: 26509823 DOI: 10.2450/2015.0070-15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 06/22/2015] [Indexed: 11/21/2022]
Abstract
BACKGROUND Molecular-based laboratory tests can predict blood group antigens and supplement serological methods, adding a unique technology to assist in resolving discrepant or incomplete blood group typing or antibody identification. Hospital transfusion services have options for integrating molecular-based methods in their routine operations. We describe here the model of a hospital-reference laboratory partnership. MATERIALS AND METHODS Blood samples for compatibility testing were obtained from patients in a 609-bed hospital serving an urban multiethnic and multiracial population. When results of blood group phenotyping by serological methods were inconclusive, samples were referred for molecular-based testing. The reference laboratory used several methods for genotyping, including polymerase chain reaction followed by restriction enzyme-linked polymorphism analysis, sequence-specific primer polymerase chain reaction and array-based approaches. Human erythrocyte antigen, RHCE and RHD single nucleotide polymorphism arrays were integrated into the laboratory as they became commercially available. RESULTS The hospital-reference laboratory model made it possible to integrate blood group genotyping promptly by current technology without the expense of new laboratory equipment or adding personnel with technical expertise. We describe ten cases that illustrate the categories of serological problems that were resolved by molecular methods. DISCUSSION In-hospital molecular testing for transfusion services has logistical advantages, but is financially impractical for most hospitals. Our model demonstrates the advantages of a hospital-reference laboratory partnership. In conclusion, hospital transfusion services can integrate molecular-based testing in their routine services without delay by establishing a partnership with a molecular blood group reference laboratory. The hospital reference-laboratory model promotes genomic medicine without the expense of new equipment and skilled personnel, while supporting the economy of centralised large-scale laboratory operations.
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