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Ramsey G, Park YA, Eder AF, Bobr A, Karafin MS, Karp JK, King KE, Pagano MB, Schwartz J, Szczepiorkowski ZM, Souers RJ, Thomas L, Delaney M. Obstetric and Newborn Weak D-Phenotype RBC Testing and Rh Immune Globulin Management Recommendations: Lessons From a Blinded Specimen-Testing Survey of 81 Transfusion Services. Arch Pathol Lab Med 2023; 147:71-78. [PMID: 35486492 DOI: 10.5858/arpa.2021-0250-cp] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2021] [Indexed: 12/31/2022]
Abstract
CONTEXT.— Modern RHD genotyping can be used to determine when patients with serologic weak D phenotypes have RHD gene variants at risk for anti-D alloimmunization. However, serologic testing, RhD interpretations, and laboratory management of these patients are quite variable. OBJECTIVE.— To obtain interlaboratory comparisons of serologic testing, RhD interpretations, Rh immune globulin (RhIG) management, fetomaternal hemorrhage testing, and RHD genotyping for weak D-reactive specimens. DESIGN.— We devised an educational exercise in which 81 transfusion services supporting obstetrics performed tube-method RhD typing on 2 unknown red blood cell challenge specimens identified as (1) maternal and (2) newborn. Both specimens were from the same weak D-reactive donor. The exercise revealed how participants responded to these different clinical situations. RESULTS.— Of reporting laboratories, 14% (11 of 80) obtained discrepant immediate-spin reactions on the 2 specimens. Nine different reporting terms were used to interpret weak D-reactive maternal RhD types to obstetricians. In laboratories obtaining negative maternal immediate-spin reactions, 28% (16 of 57) performed unwarranted antiglobulin testing, sometimes leading to recommendations against giving RhIG. To screen for excess fetomaternal hemorrhage after a weak D-reactive newborn, 47% (34 of 73) of reporting laboratories would have employed a contraindicated fetal rosette test, risking false-negative results and inadequate RhIG coverage. Sixty percent (44 of 73) of laboratories would obtain RHD genotyping in some or all cases. CONCLUSIONS.— For obstetric and neonatal patients with serologic weak D phenotypes, we found several critical problems in transfusion service laboratory practices. We provide recommendations for appropriate testing, consistent immunohematologic terminology, and RHD genotype-guided management of Rh immune globulin therapy and RBC transfusions.
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Affiliation(s)
- Glenn Ramsey
- From the Department of Pathology, Northwestern University, Chicago, Illinois (Ramsey)
| | - Yara A Park
- Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill (Park)
| | - Anne F Eder
- Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland (Eder)
| | - Aleh Bobr
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota (Bobr).,Bobr is currently located in the Department of Pathology and Microbiology, at the University of Nebraska Medical Center, Omaha. Karafin is currently located in the Department of Pathology and Laboratory Medicine, at the University of North Carolina, Chapel Hill. Schwartz is currently located in the Department of Pathology, Molecular and Cell-Based Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | | | - Julie K Karp
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (Karp)
| | - Karen E King
- Department of Pathology, Johns Hopkins University, Baltimore, Maryland (King)
| | - Monica B Pagano
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle (Pagano)
| | - Joseph Schwartz
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York (Schwartz)
| | - Zbigniew M Szczepiorkowski
- Department of Pathology and Laboratory Medicine, Dartmouth College, Hanover, New Hampshire (Szczepiorkowski)
| | - Rhona J Souers
- Department of Biostatistics (Souers), College of American Pathologists, Northfield, Illinois
| | - Lamont Thomas
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (Karp).,Department of Proficiency Testing (Thomas), College of American Pathologists, Northfield, Illinois
| | - Meghan Delaney
- The Division of Pathology & Laboratory Medicine, Children's National Hospital, and the Departments of Pathology & Pediatrics, The George Washington University School of Medicine & Health Sciences, Washington, DC (Delaney)
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2
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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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3
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Ohto H, Albert Flegel W, Safic Stanic H. When should RhD-negative recipients be spared the transfusion of DEL red cells to avoid anti-D alloimmunization? Transfusion 2022; 62:2405-2408. [PMID: 36156264 PMCID: PMC9643616 DOI: 10.1111/trf.17122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 09/04/2022] [Accepted: 09/06/2022] [Indexed: 11/30/2022]
Affiliation(s)
- Hitoshi Ohto
- Department of Mesenchymal Stem Cell Research, and Department of Blood Transfusion and Transplantation Immunology, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Willy Albert Flegel
- Department of Transfusion Medicine, NIH Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - Hana Safic Stanic
- Department of Immunohematology, Croatian Institute of Transfusion Medicine, Zagreb, Croatia
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4
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Abstract
Red blood cell (RBC) transfusion is one of the most frequently performed clinical procedures and therapies to improve tissue oxygen delivery in hospitalized patients worldwide. Generally, the cross-match is the mandatory test in place to meet the clinical needs of RBC transfusion by examining donor-recipient compatibility with antigens and antibodies of blood groups. Blood groups are usually an individual's combination of antigens on the surface of RBCs, typically of the ABO blood group system and the RH blood group system. Accurate and reliable blood group typing is critical before blood transfusion. Serological testing is the routine method for blood group typing based on hemagglutination reactions with RBC antigens against specific antibodies. Nevertheless, emerging technologies for blood group testing may be alternative and supplemental approaches when serological methods cannot determine blood groups. Moreover, some new technologies, such as the evolving applications of blood group genotyping, can precisely identify variant antigens for clinical significance. Therefore, this review mainly presents a clinical overview and perspective of emerging technologies in blood group testing based on the literature. Collectively, this may highlight the most promising strategies and promote blood group typing development to ensure blood transfusion safety.
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Affiliation(s)
- Hong-Yang Li
- Department of Blood Transfusion, China-Japan Union Hospital of Jilin University, Changchun, China
| | - Kai Guo
- Department of Transfusion Medicine, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
- National Center for Clinical Laboratories, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology, Beijing, China
- Graduate School of Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
- *Correspondence: Kai Guo
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5
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Sahoo D, Kanungo G, Behera R, Jena P. Serological comparison of weak D versus weakly reacting D by four different methods. Asian J Transfus Sci 2022. [DOI: 10.4103/ajts.ajts_34_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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6
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Al-Riyami AZ, Al Hinai D, Al-Rawahi M, Al-Hosni S, Al-Zadjali S, Al-Marhoobi A, Al-Khabori M, Al-Riyami H, Denomme GA. Molecular blood group screening in Omani blood donors. Vox Sang 2021; 117:424-430. [PMID: 34647328 DOI: 10.1111/vox.13204] [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: 06/18/2021] [Revised: 08/24/2021] [Accepted: 08/29/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND OBJECTIVES Blood group genotyping has been used in different populations. This study aims at evaluating the genotypes of common blood group antigens in the Omani blood donors and to assess the concordance rate with obtained phenotypes. MATERIAL AND METHODS Blood samples from 180 Omani donors were evaluated. Samples were typed by serological methods for the five blood group systems MNS, RH (RHD/RHCE), KEL, FY and JK. Samples were genotyped using RBC-FluoGene vERYfy eXtend kit (inno-train©). Predicted phenotypic variants for 70 red blood cell antigens among the MNS, RH (RHD/RHCE), KEL, FY, JK, DO, LU, YT, DI, VEL, CO and KN blood group systems were assessed. RESULTS Simultaneous phenotype and genotype results were available in 130 subjects. Concordance rate was >95% in all blood group systems with exception of Fy(b+) (87%). Homozygous GATA-1 mutation leading to erythroid silencing FY*02N.01 (resulting in the Fy(b-)ES phenotype) was detected in 81/112 (72%) of genotyped samples. In addition, discrepant Fyb phenotype/genotype result was obtained in 14/112 samples; 13 of which has a heterozygous GATA-1 mutation and one sample with a wild GATA genotype. D and partial e c.733C>G variants expressing the V+VS+ phenotype were found in 22/121 (18.2%) and 14/120 (11.7%) of the samples, respectively. Di(a-b+), Js(a-b+), Yt(a+b-) and Kn(a+b-) genotype frequencies were 99.4%, 95.8%, 91.9% and 97.7%, respectively. CONCLUSION In conclusion, we report a high frequency of FY*02N.01 allele due to homozygous c.-67T>C GATA-1 single-nucleotide variation. This is the first study reporting the detailed distribution of common and rare red cell genotypes in Omani blood donors.
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Affiliation(s)
- Arwa Z Al-Riyami
- Department of Haematology, Sultan Qaboos University Hospital, Muscat, Oman
| | - Dina Al Hinai
- College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Mohammed Al-Rawahi
- Department of Haematology, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Saif Al-Hosni
- Department of Haematology, Sultan Qaboos University Hospital, Muscat, Oman
| | | | - Ali Al-Marhoobi
- Department of Haematology, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Murtadha Al-Khabori
- Department of Haematology, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Hamad Al-Riyami
- Department of Genetics, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Gregory A Denomme
- Diagnostic Laboratories, Versiti Blood Center of Wisconsin, Milwaukee, Wisconsin, USA
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7
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Sadeghi-Bojd Y, Amirizadeh N, Oodi A. RHD Genotyping of Rh-Negative and Weak D Phenotype among Blood Donors in Southeast Iran. Int J Hematol Oncol Stem Cell Res 2021; 15:213-220. [PMID: 35291662 PMCID: PMC8888359 DOI: 10.18502/ijhoscr.v15i4.7476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 10/31/2020] [Indexed: 11/29/2022] Open
Abstract
Background: The D antigen is a subset of Rh blood group antigens involved in the hemolytic disease of the newborn [HDFN] and hemolytic transfusion reaction [HTR]. The hybrid Rhesus box that was created after RH gene deletion, was known as a mechanism of the Rh-negative phenotype. Hybrid marker identification is used to confirm the deletion of the RHD gene and to determine zygosity. This study aims to detect this marker in Rh-negative and weak D phenotype blood donors of the southeast of Iran. Materials and Methods: The molecular analysis of the hybrid Rhesus box was performed on the 200 Rh-negative blood donors in Sistan and Baluchestan province, southeast Iran. The presence of alleles responsible for the D variants was assessed by DNA sequencing in 26 weak D phenotype donors. Results: Of the 200 Rh-negative blood samples, 198 samples were homozygous (99%), and two samples were heterozygous (1%). Heterozygous samples had RHD*01N.73 allele and the RHD*01N.18 allele. Of the 26 samples with weak D phenotype, 16 partial DLO (61%), 4 partial DBT1 (15.3%), 2 partial DV type 2 (7.7%), 1 weak D type 1, 1 weak D type 4.2.3, 1weak D type 105 and 1 RHD (S103P) (4%) were determined. Conclusion: Since RHD gene deletion is the main mechanism of the Rh-negativity in Sistan and Baluchestan provinces, a hybrid Rhesus box marker can be used in resolving RhD typing discrepancies by RHD genotyping methods.
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Affiliation(s)
- Younes Sadeghi-Bojd
- Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
| | - Naser Amirizadeh
- Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
| | - Arezoo Oodi
- Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
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8
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Vege S, Sprogøe U, Lomas-Francis C, Jakobsen MA, Antonsen B, Aeschlimann J, Yazer M, Westhoff CM. Impact of RHD genotyping on transfusion practice in Denmark and the United States and identification of novel RHD alleles. Transfusion 2020; 61:256-265. [PMID: 32975828 DOI: 10.1111/trf.16100] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 08/17/2020] [Accepted: 08/27/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND Reduced D antigen on red blood cells (RBCs) may be due to "partial" D phenotypes associated with loss of epitope(s) and risk for alloimmunization or "weak" D phenotypes that do not lack major epitopes with absence of clinical complications. Genotyping of samples with weak and discrepant D typing is recommended to guide transfusion and RhIG prophylaxis. The goal was to compare the impact of RHD genotyping on transfusion practice in two centers serving different populations. STUDY DESIGN AND METHODS Fifty-seven samples from Denmark and 353 from the United States with weak or discrepant D typing were genotyped. RBC typing was by multiple methods and reagents. DNA isolated from white blood cells was tested with RBC-Ready Gene D weak or CDE in Denmark or RHD BeadChip in the United States. RHD was sequenced for those unresolved. RESULTS Of Caucasian samples from Denmark, 90% (n = 51) had weak D types 1, 2, or 3; two had other weak D, two partial D, and two new alleles. In diverse ethnic U.S. samples, 44% (n = 155) had weak D types 1, 2, or 3 and 56% (n = 198) had other alleles: uncommon weak D (n = 13), weak 4.0 (n = 62), partial D (n = 107), no RHD (n = 9), and new alleles (n = 7). CONCLUSION Most samples with weak or variable D typing from Denmark had alleles without risk for anti-D. In U.S. samples, 48% could safely be treated as D+, 18% may require consideration if pregnancy possible, and 34% could potentially benefit from being treated as D-. Black and multiracial ethnicities were overrepresented relative to population.
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Affiliation(s)
- Sunitha Vege
- Laboratory of Immunohematology and Genomics, New York Blood Center Enterprise, New York, New York, USA
| | - Ulrik Sprogøe
- South Danish Transfusion Service at Department of Clinical Immunology, Odense University Hospital, Odense, Denmark
| | - Christine Lomas-Francis
- Laboratory of Immunohematology and Genomics, New York Blood Center Enterprise, New York, New York, USA
| | - Marianne A Jakobsen
- South Danish Transfusion Service at Department of Clinical Immunology, Odense University Hospital, Odense, Denmark
| | - Berit Antonsen
- South Danish Transfusion Service at Department of Clinical Immunology, Odense University Hospital, Odense, Denmark
| | - Judith Aeschlimann
- Laboratory of Immunohematology and Genomics, New York Blood Center Enterprise, New York, New York, USA
| | - Mark Yazer
- South Danish Transfusion Service at Department of Clinical Immunology, Odense University Hospital, Odense, Denmark.,Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Connie M Westhoff
- Laboratory of Immunohematology and Genomics, New York Blood Center Enterprise, New York, New York, USA
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9
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RHD genotyping of serological weak D phenotypes in the Iranian blood donors and patients. Transfus Apher Sci 2020; 59:102870. [PMID: 32660892 DOI: 10.1016/j.transci.2020.102870] [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: 05/21/2020] [Revised: 06/13/2020] [Accepted: 06/19/2020] [Indexed: 11/23/2022]
Abstract
BACKGROUND Most prevalent weak D types in the Caucasians molecularly defined weak D types 1, 2 or 3 and can be managed safely as RhD-positive, conserving limited supplies of RhD-negative RBCs. Therefore, identification of RHD alleles prevalence in each population could improve the policies related to accuracy of RhD typing. The aim of this study was to determine the frequency of RHD variant alleles among donors and patients for the first time in Iran. MATERIALS AND METHODS RHD genotyping was performed on 100 blood donor and patient samples with weak D phenotype. PCR-SSP and DNA sequencing were used to identify the RHD alleles. RESULTS Molecular analysis showed only 15 samples were RHD*weak D 1(n = 13) and RHD*weak D 3(n = 2), and no cases of RHD*weak D 2 were detected. RHD*weak 15 (n = 43) was determined as the most prevalent D variants in our population and the other weak D types follows: RHD*weak 4, 5, 80 and one case of each one: RHD*weak 8, 11, 14, 100 and 105. Partial D variants also was identified in 18 samples as follows: RHD*partial DLO, DBT1, DV2, DHK and DAU-1. CONCLUSION The results of this study highlight the specific pattern of RHD status in the Iranian population. The weak D types 15 was the most common weak D type in the Iranian population. However, the screening for weak D types 1, 2 and 3 with 15 % frequency is also necessary for accurate RhD typing and developing clinical strategy of blood transfusion in weak D patients.
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10
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Khetan D, Verma A, Chaudhary RK, Shukla JS. Molecular characterisation of RhD variants in North Indian blood donor population. Transfus Med 2020; 30:295-303. [PMID: 32488899 DOI: 10.1111/tme.12690] [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: 07/18/2019] [Revised: 01/01/2020] [Accepted: 05/10/2020] [Indexed: 11/25/2022]
Abstract
OBJECTIVES A molecular analysis of serologically RhD variant samples was conducted to find the incidence of various D variants in our blood donor population. BACKGROUND Determining a blood donor's RhD phenotype and genotype is important as transfusion of units with a weak D or partial D phenotype can result in immunisation of the recipients. METHODS Samples with discrepant D and weak D phenotypes identified on testing with at least five different monoclonal anti-D antisera were considered serological RhD variant and subjected to molecular testing (Massarray kit, Agena Bioscience, San Diego) for variant RHD gene. RESULTS A total of 39 samples, including 19 RhD discrepant samples and 20 weak D samples, were identified as serological RhD variant from a total of 4386 samples. Thirteen (13/39) samples carried variants leading to weak D phenotype, and eight samples had variants leading to partial D categories. Seven samples (7) could not be characterised, whereas 11 samples were identified as Rh negative (RHD*01N.01) after molecular testing. Overall incidence of D variants in the study population was 0.48%. RHD*weak D type 1(5, 0.1%) and RHD*DFR1 (5, 1%) were the most common variants identified. CONCLUSIONS Few samples with weak reaction on serological testing were found to be partial D variant and vice versa. Donor centres should develop a protocol for genotyping of samples with aberrant results on serological testing for assessing the actual RhD status of an individual as results of serological testing may be misleading.
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Affiliation(s)
- Dheeraj Khetan
- Department of Transfusion Medicine, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| | - Anviti Verma
- Department of Transfusion Medicine, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| | - Rajendra K Chaudhary
- Department of Transfusion Medicine, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
| | - Jai Shankar Shukla
- Department of Transfusion Medicine, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
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11
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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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12
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Sandler SG, Flegel WA. Does transfusion of Asian-type DEL red blood cells to D- recipients cause D alloimmunization? Transfusion 2019; 59:2455-2458. [PMID: 31008519 DOI: 10.1111/trf.15323] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 02/20/2019] [Accepted: 03/01/2019] [Indexed: 12/17/2022]
Affiliation(s)
- S Gerald Sandler
- Department of Pathology and Laboratory Medicine, MedStar Georgetown University Hospital, Washington, DC
| | - Willy A Flegel
- Department of Pathology and Laboratory Medicine, MedStar Georgetown University Hospital, Washington, DC.,Department of Laboratory Medicine, NIH Clinical Center, National Institutes of Health, Bethesda, Maryland
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13
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Guzijan G, Jovanovic Srzentic S, Pavlovic Jankovic N, Djilas I, Lilić M. Implementation of Molecular RHD Typing at Two Blood Transfusion Institutes from Southeastern Europe. Transfus Med Hemother 2019; 46:114-120. [PMID: 31191198 DOI: 10.1159/000496751] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 01/08/2019] [Indexed: 11/19/2022] Open
Abstract
Introduction Determination of RhD variants in blood donors, pregnant women, and newborns is important for transfusion strategies, in order to prevent RhD alloimmunisation and hemolytic disease of fetuses and newborns. Implementation of molecular RHD typing in two transfusion institutes is presented in this article, from Banja Luka (Bosnia and Herzegovina) and Belgrade (Serbia). Study Design and Methods Blood donors' RhD was checked by direct agglutination assays (tube) and indirect antiglobulin test (gel). Molecular RHD typing was performed by PCR-SSP with fluorometric signal detection in both centres. Donors were selected by weak RhD serological reactivity (Banja Luka, 85 samples; Belgrade, 62 samples) or serologically RhD-negative C/E-positive results (Banja Luka, 92 samples; Belgrade, 61 samples). Results Among serologically determined weak D donors from the institute from Banja Luka, weak D type 3 was the most frequent (58.8%), followed by type 1 (35.3%) and DNB (1.2%), whereas results obtained at the Belgrade institute were distributed between weak D type 1 (41.9%), type 3 (30.7%), type 14 (6.5%), type 15 (1.6%), and DNB with anti-D (1.6%). In 17.7% of serologically typed weak D samples from the Belgrade institute, the molecular typing result was standard D. Additionally, RHD presence was detected in 9.8% of serologically RhD-negative, C/E-positive samples from both institutes. Conclusion Rh molecular testing was successfully implemented in both blood transfusion institutes in Banja Luka and Belgrade. This study proved the efficiency of serological algorithms for weak D, as well as the presence of the RHD gene among serologically tested RhD-negative, C/E-positive samples.
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Affiliation(s)
- Gordana Guzijan
- Institute for Transfusion Medicine of Republika Srpska, Banja Luka, Bosnia and Herzegovina, Belgrade, Serbia.,Medical Faculty, University of Banja Luka, Banja Luka, Bosnia and Herzegovina, Belgrade, Serbia
| | | | | | - Iva Djilas
- Blood Transfusion Institute of Serbia, Belgrade, Serbia
| | - Marko Lilić
- Josip Juraj Strossmayer University of Osijek, Osijek, Croatia
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14
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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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15
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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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Abstract
Abstract
Background: RH genotyping studies have been conducted mainly in people of Caucasian and African descent. There is limited information regarding the molecular basis for RH genotypes in Malaysia.
Objectives: To investigate the prevalence and characteristics of RHCE genotypes among different ethnic groups in Malaysia.
Methods: A total of 1014 whole blood samples were obtained from donors from 4 different ethnic groups (360 Malays, 434 Chinese, 164 Indians, and 56 others). All samples were phenotyped for C, c, D, E, and e using standard serologic methods and genotyped using polymerase chain reaction (PCR)-based analysis.
Results: In the blood samples that we analyzed, the distribution of RH genotype antigens was significantly different among the various ethnic groups. Our findings showed that CCDee is the most common in Malaysian blood donors; 18.4% (187/1014) compared with other genotypes. The ccDEE genotype is more prevalent in the Chinese: 65.6% (82/125), and the ccee genotype is more prevalent in Indians: 47.1% (65/138). There were discrepancies between phenotypes and genotypes. There were 17 (1.7%) discrepancies in RH C/c genotyping results and of these 47% (8/17) occurred in Malays. Discrepancies in RH E/e results occurred in 3 samples (0.3%).
Conclusions: Our study provides a database for the distribution of RH genotypes of donors from the major ethnic groups in Malaysia. Methods used in this study are useful for comparing the phenotypes and genotypes. Further investigation should be conducted to study the causes of these discrepancies using other molecular based techniques.
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Affiliation(s)
- Rozi Hanisa Musa
- Advanced Medical and Dental Institute (AMDI), Universiti Sains Malaysia, Bertam, Penang, Malaysia
| | | | - Yasmin Ayob
- National Blood Centre, Kuala Lumpur, Malaysia
| | - Narazah Mohd Yusoff
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, Penang, Malaysia
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Clarke G, Hannon J, Berardi P, Barr G, Cote J, Fallis R, Alport T, Lane D, Petraszko T, Ochoa G, Goldman M. Resolving variable maternal D typing using serology and genotyping in selected prenatal patients. Transfusion 2016; 56:2980-2985. [DOI: 10.1111/trf.13798] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 07/20/2016] [Accepted: 07/22/2016] [Indexed: 11/28/2022]
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Zacarias JMV, Pereira EMDF, Visentainer JEL, Guelsin GAS, de Melo FC, Sell AM. Frequency of RHD variants in Brazilian blood donors from Parana State, Southern Brazil. Transfus Apher Sci 2016; 55:120-4. [DOI: 10.1016/j.transci.2016.04.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 04/27/2016] [Accepted: 04/29/2016] [Indexed: 11/24/2022]
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Yazer MH, Brunker PA, Bakdash S, Tobian AA, Triulzi DJ, Earnest V, Harris S, Delaney M. Low incidence of D alloimmunization among patients with a serologic weak D phenotype after D+ transfusion. Transfusion 2016; 56:2502-2509. [DOI: 10.1111/trf.13725] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Revised: 06/03/2016] [Accepted: 06/06/2016] [Indexed: 11/30/2022]
Affiliation(s)
- Mark H. Yazer
- Department of Pathology; University of Pittsburgh; Pittsburgh Pennsylvania
- The Institute for Transfusion Medicine; Pittsburgh Pennsylvania
| | | | - Suzanne Bakdash
- Department of Clinical Pathology; The Cleveland Clinic; Cleveland Ohio
| | | | - Darrell J. Triulzi
- Department of Pathology; University of Pittsburgh; Pittsburgh Pennsylvania
- The Institute for Transfusion Medicine; Pittsburgh Pennsylvania
| | | | | | - Meghan Delaney
- Department of Laboratory Medicine; University of Washington
- Bloodworks NW; Seattle Washington
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Welsh KJ, Bai Y. Pathology Consultation on Patients With a Large Rh Immune Globulin Dose Requirement. Am J Clin Pathol 2016; 145:744-51. [PMID: 27267375 DOI: 10.1093/ajcp/aqw051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES To review the differential diagnosis and laboratory issues for women with a large calculated dose of Rh immune globulin (RhIG). METHODS A case-based approach is used to review the differential diagnosis of patients with a large calculated dose of RhIG, RhIG dosing for women with baseline elevations in hemoglobin F, the formulations of RhIG, and issues for the transfusion medicine service with the release of large doses of RhIG. RESULTS A large fetomaternal bleed after delivery requiring multiple doses of RhIG is rare. Such patients may require intravenous RhIG to avoid multiple injections. Patients with a large percentage of circulating fetal RBCs should be evaluated for a disorder of hemoglobin synthesis and, if present, should have quantification of the circulating fetal RBCs by flow cytometry. CONCLUSIONS Accurate laboratory evaluation of women with large fetomaternal bleeds is essential for appropriate RhIG administration.
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Affiliation(s)
- Kerry J Welsh
- From the Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at Houston
| | - Yu Bai
- From the Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at Houston.
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Abstract
The clinical importance of blood group antigens relates to their ability to evoke immune antibodies that are capable of causing hemolysis. The most important antigens for safe transfusion are ABO and D (Rh), and typing for these antigens is routinely performed for patients awaiting transfusion, prenatal patients, and blood donors. Typing for other blood group antigens, typically of the Kell, Duffy, Kidd, and MNS blood groups, is sometimes necessary, for patients who have, or are likely to develop antibodies to these antigens. The most commonly used typing method is serological typing, based on hemagglutination reactions against specific antisera. This method is generally reliable and practical for routine use, but it has certain drawbacks. In recent years, molecular typing has emerged as an alternative or supplemental typing method. It is based on detecting the polymorphisms and mutations that control the expression of blood group antigens, and using this information to predict the probable antigen type. Molecular typing methods are useful when traditional serological typing methods cannot be used, as when a patient has been transfused and the sample is contaminated with red blood cells from the transfused blood component. Moreover, molecular typing methods can precisely identify clinically significant variant antigens that cannot be distinguished by serological typing; this capability has been exploited for the resolution of typing discrepancies and shows promise for the improved transfusion management of patients with sickle cell anemia. Despite its advantages, molecular typing has certain limitations, and it should be used in conjunction with serological methods.
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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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24
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Sandler SG, Flegel WA, Westhoff CM, Denomme GA, Delaney M, Keller MA, Johnson ST, Katz L, Queenan JT, Vassallo RR, Simon CD. It's time to phase in RHD genotyping for patients with a serologic weak D phenotype. College of American Pathologists Transfusion Medicine Resource Committee Work Group. Transfusion 2015; 55:680-9. [PMID: 25438646 PMCID: PMC4357540 DOI: 10.1111/trf.12941] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/07/2014] [Accepted: 10/07/2014] [Indexed: 11/29/2022]
Affiliation(s)
- S Gerald Sandler
- Department of Pathology and Laboratory Medicine, MedStar Georgetown University Hospital, Washington, DC
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25
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Haspel RL, Westhoff CM. How do I manage Rh typing in obstetric patients? Transfusion 2015; 55:470-4. [DOI: 10.1111/trf.12995] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 12/03/2014] [Accepted: 12/03/2014] [Indexed: 11/27/2022]
Affiliation(s)
- Richard L. Haspel
- Department of Pathology; Beth Israel Deaconess Medical Center and Harvard Medical School; Boston Massachusetts
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Körmöczi GF, Mayr WR. Responder individuality in red blood cell alloimmunization. ACTA ACUST UNITED AC 2014; 41:446-51. [PMID: 25670932 DOI: 10.1159/000369179] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 10/20/2014] [Indexed: 01/12/2023]
Abstract
Many different factors influence the propensity of transfusion recipients and pregnant women to form red blood cell alloantibodies (RBCA). RBCA may cause hemolytic transfusion reactions, hemolytic disease of the fetus and newborn and may be a complication in transplantation medicine. Antigenic differences between responder and foreign erythrocytes may lead to such an immune answer, in part with suspected specific HLA class II associations. Biochemical and conformational characteristics of red blood cell (RBC) antigens, their dose (number of transfusions and pregnancies, absolute number of antigens per RBC) and the mode of exposure impact on RBCA rates. In addition, individual circumstances determine the risk to form RBCA. Responder individuality in terms of age, sex, severity of underlying disease, disease- or therapy-induced immunosuppression and inflammation are discussed with respect to influencing RBC alloimmunization. For particular high-risk patients, extended phenotype matching of transfusion and recipient efficiently decreases RBCA induction and associated clinical risks.
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Affiliation(s)
- Günther F Körmöczi
- Department of Blood Group Serology and Transfusion Medicine, Medical University of Vienna, Austria
| | - Wolfgang R Mayr
- Department of Blood Group Serology and Transfusion Medicine, Medical University of Vienna, Austria
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27
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Serologic findings of RhD alleles in Egyptians and their clinical implications. Transfus Apher Sci 2014; 51:184-7. [PMID: 25219636 DOI: 10.1016/j.transci.2014.08.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 08/19/2014] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Serologic discrepancies caused by various reactivity of D variants can only be resolved by the use of RhD genotyping. However, this strategy cannot be applied routinely due to the cost and feasibility. It has been documented that D variants are demonstrated among individuals with positivity for at least C or E antigens. It is considered to be affordable for some countries to test D negative donors who are C or E positive for D variants. It was proposed that an algorithm could be found based on distinct serologic features that matches the Egyptian genetic frequency data, and correctly assigns donors and patients, using the least possible expenses. MATERIALS AND METHODS Samples with the most prevalent weak D and partial D were investigated for their RhCE phenotype. Routine D typing by immediate spin (IS) tube method was performed in parallel with an automated gel test, and the reactivity results of D variants with both techniques were compared. RESULTS Among 31 D variants, only 5 were C or E positive (16.1 %). R0r phenotype was associated with the remaining 26 samples (83.9%) and constituted weak D types 4.2 (38.5%), and 4.0/4.1 (11.5%), partial DIII (34.6%), and partial DV (15.4%). Gel reacted strongly with partial DIII and DV. Ten samples with DIII and DV typed as D positive with IS. All weak D were positive by indirect antiglobulin test (IAT), while all partial D were positive by gel and IAT. CONCLUSION Guidelines for RhD workup should be adjusted to match population data. Detection of D variants among C or E positive donors may not be an optimal strategy for Egyptians. Serology cannot discriminate weak D from partial D, but may provide a clue about the probable D variant to be tested molecularly with the appropriate kit. Reagent selection is important to correctly assign donors and patients with the DIII and DV types.
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Affiliation(s)
- Willy A Flegel
- From the Laboratory Services Section, Department of Transfusion Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland (Drs Flegel and Tholpady); and the Department of Pathology, Virginia Commonwealth University Health System, Richmond, Virginia (Dr Roseff)
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Sandler SG, Roseff SD, Domen RE, Shaz B, Gottschall JL. Policies and procedures related to testing for weak D phenotypes and administration of Rh immune globulin: results and recommendations related to supplemental questions in the Comprehensive Transfusion Medicine survey of the College of American Pathologists. Arch Pathol Lab Med 2014; 138:620-5. [PMID: 24786120 DOI: 10.5858/arpa.2013-0141-cp] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
CONTEXT Advances in RHD genotyping offer an opportunity to update policies and practices for testing weak D phenotypes and administration of Rh immune globulin to postpartum women. OBJECTIVES To repeat questions from a 1999 College of American Pathologists proficiency test survey, to evaluate current practices for testing for weak D and administration of Rh immune globulin, and to determine whether there is an opportunity to begin integrating RHD genotyping in laboratory practice. DESIGN The College of American Pathologists Transfusion Medicine Resource Committee sent questions from the 1999 survey to laboratories that participated in the 2012 proficiency test survey. The results of the 2012 survey were compared with those from 1999. Results from published RHD genotyping studies were analyzed to determine if RHD genotyping could improve current policies and practices for serological Rh typing. RESULTS More than 3100 survey participants responded to the 2012 questions. The most significant finding was a decrease in the number of transfusion services performing a serological weak D test on patients as a strategy to manage those with a weak D as Rh negative (from 58.2% to 19.8%, P < .001). Data from RHD genotyping studies indicate that approximately 95% of women with a serological weak D could be managed safely and more logically as Rh positive. CONCLUSIONS Selective integration of RHD genotyping policies and practices could improve the accuracy of Rh typing results, reduce unnecessary administration of Rh immune globulin in women with a weak D, and decrease transfusion of Rh-negative red blood cells in most recipients with a serological weak D phenotype.
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Affiliation(s)
- S Gerald Sandler
- From the Department of Pathology and Laboratory Medicine, MedStar Georgetown University Hospital, Washington, DC (Dr Sandler); Department of Pathology, Virginia Commonwealth University School of Medicine, Richmond (Dr Roseff); Department of Pathology, Penn State College of Medicine, Hershey, Pennsylvania (Dr Domen); New York Blood Center, New York, New York (Dr Shaz); and Blood Center of Wisconsin and Department of Pathology, Medical College of Wisconsin, Milwaukee (Dr Gottschall)
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Abstract
Starting in 2013, blood donors must be tested at least using: (1) one monoclonal anti-D and one anti-CDE (alternatively full RhCcEe phenotyping), and (2) all RhD negative donors must be tested for RHD exons 5 and 10 plus one further exonic, or intronic RHD specificity, according to the guidelines of the Blood Transfusion Service of the Swiss Red Cross (BTS SRC). In 2012 an adequate stock of RHD screened donors was built. Of all 25,370 RhD negative Swiss donors tested in 2012, 20,015 tested at BTS Berne and 5355 at BTS Zürich, showed 120 (0.47%) RHD positivity. Thirty-seven (0.15%) had to be redefined as RhD positive. Routine molecular RHD screening is reliable, rapid and cost-effective and provides safer RBC units in Switzerland.
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Nakashidze I, Diasamidze A, Baratashvili D, Nagervadze M, Alibegashvili M, Ramishvili L, Gordeziani M, Khazaradze A, Kotrikadze N. Alteration of Sex and Non-Sex Hormones and Distribution Features of Blood ABO System Groups among the Women with Uterine Body Tumors. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/jct.2014.55047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Orzińska A, Guz K, Polin H, Pelc-Kłopotowska M, Bednarz J, Gieleżyńska A, Sliwa B, Kowalewska M, Pawłowska E, Włodarczyk B, Malaga Alicja Żmudzin M, Krzemienowska M, Srivastava K, Michalewska B, Gabriel C, Flegel WA, Brojer E. RHD variants in Polish blood donors routinely typed as D-. Transfusion 2013; 53:2945-53. [PMID: 23634715 PMCID: PMC5497842 DOI: 10.1111/trf.12230] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 01/10/2013] [Accepted: 02/10/2013] [Indexed: 11/30/2022]
Abstract
BACKGROUND Blood donors exhibiting a weak D or DEL phenotypical expression may be mistyped D- by standard serology hence permitting incompatible transfusion to D- recipients. Molecular methods may overcome these technical limits. Our aim was to estimate the frequency of RHD alleles among the apparently D- Polish donor population and to characterize its molecular background. STUDY DESIGN AND METHODS Plasma pools collected from 31,200 consecutive Polish donors typed as D- were tested by real-time polymerase chain reaction (PCR) for the presence of RHD-specific markers located in Intron 4 and Exons 7 and 10. RHD+ individuals were characterized by PCR or cDNA sequencing and serology. RESULTS Plasma cross-pool strategy revealed 63 RHD+ donors harboring RHD*01N.03 (n = 17), RHD*15 (n = 12), RHD*11 (n = 7), RHD*DEL8 (n = 3), RHD*01W.2 (n = 3), RHD-CE(10) (n = 3), RHD*01W.3, RHD*01W.9, RHD*01N.05, RHD*01N.07, RHD*01N.23, and RHD(IVS1-29G>C) and two novel alleles, RHD*(767C>G) (n = 3) and RHD*(1029C>A). Among 47 cases available for serology, 27 were shown to express the D antigen CONCLUSION 1) Plasma cross-pool strategy is a reliable and cost-effective tool for RHD screening. 2) Only 0.2% of D- Polish donors carry some fragments of the RHD gene; all of them were C or E+. 3) Almost 60% of the detected RHD alleles may be potentially immunogenic when transfused to a D- recipient.
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Affiliation(s)
- Agnieszka Orzińska
- Department of Immunohematology and Immunology of Transfusion Medicine, Institute of Haematology and Blood Transfusion, Warsaw, Poland; Regional Blood Transfusion Centers in Warsaw, Kraków, Gdańsk, Racibórz, Kalisz, Kielce, Radom, Poland; Red Cross Transfusion Centre of Upper Austria, Linz, Austria; Department of Transfusion Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland
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Abstract
Patients with the most common weak D types 1, 2, and 3 can be safely considered D positive. We evaluated 1,113 Rh-negative Egyptian samples for weak D expression to propose a cost-effective strategy related to D variant testing. D variants were tested using polymerase chain reaction with sequence-specific priming. Fifty samples were D variants (4.5%): weak D type 4.2 (32%), weak D type 4.0/4.1 (16%), and weak D type 15 (2%). Fifteen (62.5%) of 24 samples were identified serologically as partial D. We also studied the probability of the development of anti-D in 52 Rh-negative children with thalassemia who were receiving units for which weak D was not tested. Anti-D alloimmunization was observed in 63.5% of patients with thalassemia. It is prudent to implement weak D typing in Egyptian donors. Weak D variants of Egyptians are significantly different compared with Caucasians. Ethnicity must be taken into consideration when developing clinical and prenatal strategies related to D variants.
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Mota M, Dezan M, Valgueiro MC, Sakashita AM, Kutner JM, Castilho L. RHD allelic identification among D-Brazilian blood donors as a routine test using pools of DNA. J Clin Lab Anal 2012; 26:104-8. [PMID: 22467325 DOI: 10.1002/jcla.21489] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND RHD alleles leading to a reduced expression of D antigen of the red blood cell (RBC) surface may be erroneously typed as D- by serology and may cause anti-D immunizations when transfused to recipients. METHODS To determine the occurrence of such alleles among apparent D- blood donors, molecular typing was implemented as a routine test using a pool of DNA. A total of 2,450 pretyped D- samples were tested in pools of 10 for the RHD-specific polymorphism in intron 4 and exon 7. Samples in polymer chain reaction (PCR) positive pools were individually reevaluated by exon-specific PCRs, sequencing, and serologic methods. RESULTS Among 2,450 serologically D- blood donor samples tested, 101 (4.1%) carried the RHD gene. Nonfunctional RHD (RHDψ, RHD*CE(2-9)-D, and RHD*CE(3-7)-D), different weak D alleles such as RHD*weak D type 1, RHD*weak D type 4.3, RHD*weak D type 5, RHD*weak D type 38, and RHD*DEL were identified. CONCLUSION We employed a PCR-based assay for RHD as a routine test using pools of ten DNA blood donor samples. The integration of RHD genotyping into the routine screening program using pools of DNA samples was straightforward. As a consequence, 19 (0.8%) blood donors carrying a weak D and Del phenotypes with the potential of causing anti-D immunizations in recipients were reclassified as D+. For each population, it would be necessary to adapt the RHD genotyping strategy to the spectrum of prevalent alleles.
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Affiliation(s)
- Mariza Mota
- Department of Hemotherapy, Albert Einstein Hospital, São Paulo, SP, Brazil.
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35
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Abstract
BACKGROUND A woman's candidacy for Rh immune globulin depends on whether her blood type is Rh-positive (D antigen-positive) or Rh-negative (D antigen-negative). New molecular blood-typing methods have identified variant D antigens, which may be reported as Rh-positive or Rh-negative depending on the laboratory method. We describe a case illustrating the effect of the new laboratory methods on a woman's candidacy for Rh immune globulin and present recommendations for interpreting the new test results. CASE A 40-year-old woman presented for management of her third pregnancy. During her first pregnancy, she was typed as Rh-positive ("D") and did not receive Rh immune globulin. During her second pregnancy, she was typed as Rh-negative, in accordance with revised Rh-typing procedures. Anti-D antibody was detected. During her third pregnancy, she was genotyped as a partial D antigen, which was reported as Rh-negative. CONCLUSION Revisions in laboratory procedures for Rh typing may present as a change in the Rh blood type of pregnant women-and as a change in their eligibility for Rh immune globulin.
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Cruz BR, Chiba AK, Moritz E, Bordin JO. RHD alleles in Brazilian blood donors with weak D or D-negative phenotypes. Transfus Med 2011; 22:84-9. [DOI: 10.1111/j.1365-3148.2011.01129.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
During the last decade a number of blood establishments started using molecular methods for typing a subset of their blood donors for minor red cell antigens as a part of their routine work. It can be expected that this development will continue and that DNA testing will take a significant role in future. A sufficient number of antigen-typing in the donor-database allows for the efficient supply of red cell units for patients who carry irregular antibodies directed to red cell antigens. Therefore blood centres often operate antigen typing programs for a subset of their repeat donors. Large-scale donor typing programs are labour-intensive and costly. DNA testing is a feasible alternative to standard serological assays. The most important advantage is the easy access to a spectrum of hundreds of antigens independent of the availability of serological reagents. Besides, that there are both positive, but also less favourable aspects, which are related to the different particular methods and platforms available for molecular testing. Several of them enable medium- and high-throughput applications and some are more cost-efficient than serology.
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Affiliation(s)
- Christof Jungbauer
- Austrian Red Cross, Blood Service for Vienna, Lower Austria and Burgenland, Vienna Blood Centre, Wiedner Hauptstraße 32, 1040 Vienna, Austria.
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Pham BN, Roussel M, Peyrard T, Beolet M, Jan-Lasserre V, Gien D, Ripaux M, Bourgouin S, Kappler-Gratias S, Rouger P, Pennec PYL. Anti-D investigations in individuals expressing weak D Type 1 or weak D Type 2: allo- or autoantibodies? Transfusion 2011; 51:2679-85. [DOI: 10.1111/j.1537-2995.2011.03207.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Krog GR, Clausen FB, Berkowicz A, Jørgensen L, Rieneck K, Nielsen LK, Dziegiel MH. Is current serologic RhD typing of blood donors sufficient for avoiding immunization of recipients? Transfusion 2011; 51:2278-85. [PMID: 21569040 DOI: 10.1111/j.1537-2995.2011.03156.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Avoiding immunization with clinically important antibodies is a primary objective in transfusion medicine. Therefore, it is central to identify the extent of D antigens that escape routine RhD typing of blood donors and to improve methodology if necessary. STUDY DESIGN AND METHODS We screened 5058 D- donors for the presence of the RHD gene, targeting Exons 5, 7, and 10 with real-time polymerase chain reaction. Samples that were positive in the screen test were investigated further by adsorption-elution, antibody consumption, flow cytometry, and sequencing of all RHD exons with intron-specific primers. Lookback was performed on all recipients of RBCs from RHD+ donors. RESULTS We found 13 RHD+ samples (0.26%). No variants or chimeras were found. Characterization of DNA revealed a novel DEL type (IVS2-2 A>G). In the lookback of the 136 transfusions with subsequent antibody follow-up, of which 13 were from DEL donors, one recipient developed anti-D. However, in this case, a competing and more likely cause of immunization was the concurrent transfusion of D+ platelets. Eleven recipients were immunized with 13 antibodies different from anti-D, of which five were anti-K. CONCLUSION In our laboratory, serologic RhD typing was safe. We detected all D variants and only missed DEL types. In assessing the immunization risk we included a DEL donor, found previous to this study, that did immunize a recipient with anti-D. We conclude that inadvertent immunization with D antigens in our setting was rare and in the order of 1.4 in 100,000 D- transfusions.
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Affiliation(s)
- Grethe Risum Krog
- Department of Clinical Immunology, Copenhagen University Hospital, Copenhagen, Denmark.
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Abstract
Rhesus is the clinically most important protein-based blood group system. It represents the largest number of antigens and the most complex genetics of the 30 known blood group systems. The RHD and RHCE genes are strongly homologous. Some genetic complexity is explained by their close chromosomal proximity and unusual orientation, with their tail ends facing each other. The antigens are expressed by the RhD and the RhCE proteins. Rhesus exemplifies the correlation of genotype and phenotype, facilitating the understanding of general genetic mechanisms. For clinical purposes, genetic diagnostics of Rhesus antigens will improve the cost-effective development of transfusion medicine.
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Affiliation(s)
- Willy A Flegel
- Department of Transfusion Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20892, United States.
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Hirose TG, Mays DA. The safety of RhIG in the prevention of haemolytic disease of the newborn. J OBSTET GYNAECOL 2009; 27:545-57. [PMID: 17896248 DOI: 10.1080/01443610701469941] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- T G Hirose
- Department of Pathology and Laboratory Medicine, Good Samaritan Hospital, Los Angeles, CA 90017, USA.
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Veldhuisen B, van der Schoot CE, de Haas M. Blood group genotyping: from patient to high-throughput donor screening. Vox Sang 2009; 97:198-206. [PMID: 19548962 DOI: 10.1111/j.1423-0410.2009.01209.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Blood group antigens, present on the cell membrane of red blood cells and platelets, can be defined either serologically or predicted based on the genotypes of genes encoding for blood group antigens. At present, the molecular basis of many antigens of the 30 blood group systems and 17 human platelet antigens is known. In many laboratories, blood group genotyping assays are routinely used for diagnostics in cases where patient red cells cannot be used for serological typing due to the presence of auto-antibodies or after recent transfusions. In addition, DNA genotyping is used to support (un)-expected serological findings. Fetal genotyping is routinely performed when there is a risk of alloimmune-mediated red cell or platelet destruction. In case of patient blood group antigen typing, it is important that a genotyping result is quickly available to support the selection of donor blood, and high-throughput of the genotyping method is not a prerequisite. In addition, genotyping of blood donors will be extremely useful to obtain donor blood with rare phenotypes, for example lacking a high-frequency antigen, and to obtain a fully typed donor database to be used for a better matching between recipient and donor to prevent adverse transfusion reactions. Serological typing of large cohorts of donors is a labour-intensive and expensive exercise and hampered by the lack of sufficient amounts of approved typing reagents for all blood group systems of interest. Currently, high-throughput genotyping based on DNA micro-arrays is a very feasible method to obtain a large pool of well-typed blood donors. Several systems for high-throughput blood group genotyping are developed and will be discussed in this review.
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Affiliation(s)
- B Veldhuisen
- Sanquin Research, Amsterdam and Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
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Flegel WA, von Zabern I, Wagner FF. Six years' experience performing RHD genotyping to confirm D- red blood cell units in Germany for preventing anti-D immunizations. Transfusion 2009; 49:465-71. [PMID: 19243542 PMCID: PMC10690736 DOI: 10.1111/j.1537-2995.2008.01975.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Red blood cell (RBC) units of D+ donors are falsely labeled D- if regular serologic typing fails to detect low D antigen expression or chimerism. The limitations of serology can be overcome by molecular typing. STUDY DESIGN AND METHODS In January 2002, we introduced a polymerase chain reaction (PCR)-based assay for RHD as a routine test for first-time donors who typed D- by serologic methods including the indirect antiglobulin test. Samples were tested in pools of 20 for the RHD-specific polymorphism in Intron 4. RHD alleles were identified by PCR and nucleotide sequencing. RESULTS Within 6 years, 46,133 serologically D- first-time donors were screened for the RHD gene. The prevalence of RHD gene carriers detected by this method was 0.21 percent. Twenty-three RHD alleles were found of which 15 were new. Approximately one-half of the RHD gene carriers harbored alleles expressing a DEL phenotype resulting in a prevalence of 0.1 percent. CONCLUSION The integration of RHD genotyping into the routine screening program was practical. We report 6 years' experience of this donor testing policy, which is not performed in most transfusion services worldwide. RBC units of donors with DEL phenotype have been reported to anti-D immunize D- recipients. We transferred those donors to the D+ donor pool with the rationale of preventing anti-D immunizations, especially dreaded in pregnancies. For each population, it will be necessary to adapt the RHD genotyping strategy to the spectrum of prevalent alleles.
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Affiliation(s)
- Willy A Flegel
- German Red Cross (DRK) Blood Donor Service Baden-Württemberg-Hessen, Institute of Clinical Transfusion Medicine and Immunogenetics Ulm, Ulm, Germany.
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Lai M, Grasso C, Boschi I, D'Onofrio G, Pascali V, Leone G. Characterization of anti-D monoclonal antibody reagents based on their reactivity with the weak D phenotype. Transfusion 2009; 49:937-42. [PMID: 19175552 DOI: 10.1111/j.1537-2995.2008.02066.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Anti-D monoclonal antibody (MoAb) reagents have improved D typing in routine tests. However, they exhibit a wide range of reactivity with the weak D phenotype depending on the characteristics of the different MoAbs used. We analyzed the reactivity of immunoglobulin (IgM) anti-D by cluster analysis to characterize MoAb that have similar reactivities with the weak D phenotype. STUDY DESIGN AND METHODS We used 36 consecutive samples with weak D phenotype in routine testing and determined their reactivity with different IgM and IgG anti-D MoAbs. The samples were characterized as belonging to a weak D type or category using commercial molecular biology kits. RESULTS The various anti-D MoAbs showed a wide grade of reactivity with the weak D samples. Similarities and dissimilarities in the behavior of the anti-D MoAbs with the weak D phenotype samples were detected with cluster analysis and the multidimensional scaling analysis. These analyses indicated different families of MoAbs characterized as having a high degree of homogeneity in their reactivity with the weak D phenotype. Between these MoAb families, the most effective at reacting with the weak D phenotype were RUM-1 and 175-2. CONCLUSIONS The results show that it is possible to classify the anti-D MoAbs on the basis of their reactivity with the weak D phenotype. This provides information about different MoAbs' properties on the basis of their belonging to a given of anti-D family.
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Affiliation(s)
- Marco Lai
- Immunohematology Laboratory, Transfusion Centre, Catholic University of Sacred Heart, Rome, Italy.
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Le Maréchal C, Guerry C, Benech C, Burlot L, Cavelier B, Porra V, Delamaire M, Férec C, Chen JM. Identification of 12 novel RHD alleles in western France by denaturing high-performance liquid chromatography analysis. Transfusion 2007; 47:858-63. [PMID: 17465951 DOI: 10.1111/j.1537-2995.2005.00631.x-i1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Unlike the standard RHD+ or RHD- alleles, serologic determination of weak or partial D alleles is often not clear-cut. Most importantly, rare weak D alleles, not typed by serology, are prone to alloimmunization when transfused with D+ blood. Although more than 100 RHD variants have currently been reported, many more rare alleles probably remain to be identified. STUDY DESIGN AND METHODS To identify novel unusual RHD alleles, genomic DNA samples were collected from 333 blood donors or recipients in western France. All displayed ambiguity for D phenotype as determined by routinely used serologic reagents and analyzed by means of denaturing high-performance liquid chromatography (DHPLC) analysis in parallel with direct sequencing. RESULTS For the first time it has been established that a reliable DHPLC-based approach potentiates the rapid screening of the entire RHD gene-coding sequence. In so doing, a total of 12 novel RHD alleles were identified. Except for the null allele that is in trans with a Weak D type 4 allele, the predicted effects of the other new alleles on gene expression correlated well with the discrepant routine D phenotype results. In particular, the carrier of the p.Leu214Phe missense mutation developed alloanti-D antibodies after transfusion of D+ blood. CONCLUSION The identification of 12 novel RHD alleles represents a significant addition to the known repertoire of unusual RHD variants and, at the same time, serves to deepen our understanding of the molecular basis of weak and partial D. The accurate molecular typing of RHD alleles would allow to reduce the alloimmunization risk.
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Flegel WA, Denomme GA, Yazer MH. On the Complexity of D Antigen Typing: A Handy Decision Tree in the Age of Molecular Blood Group Diagnostics. JOURNAL OF OBSTETRICS AND GYNAECOLOGY CANADA 2007; 29:746-52. [PMID: 17825140 DOI: 10.1016/s1701-2163(16)32606-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
RH is the most complex of all 29 blood group systems. New discoveries relating to the RHD gene, and an appreciation of its variant phenotypes such as weak D and partial D, have challenged the way that D status is assigned to both blood donors and blood product recipients. This concise review introduces the current concepts of weak D and partial D and how the identification of these variants has influenced the testing methods for the D antigen. We demonstrate how molecular tests of the RHD gene can and should be used in resolving serological discrepancies, in particular in pregnant women.
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Affiliation(s)
- Willy A Flegel
- Institute for Transfusion Medicine, University Hospital Ulm, Germany
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Abstract
BACKGROUND Molecular methods for blood group genotyping became available more than 10 years ago as one major aspect of immunogenetics. Since then, the clinical applications have been expanded and refined. Their implementation varies considerably among different health-care systems, notably between North America and Europe. STUDY DESIGN This summary is based on studies published mostly during the last 3 years and on workshop reports from the German and Swiss transfusion societies. It represents an edited transcript of the author's presentation given at the Workshop on Molecular Methods in Immunohematology organized by the Food and Drug Administration (FDA) in Bethesda on September 25, 2006. RESULTS Current applications of blood group genotyping in Germany, Switzerland, and Austria are detailed: weak D testing in patients and pregnant women; blood group genotyping in perinatal care, in patients who received a transfusion, and in patients with immunohematologic problems; RHD genotyping in donors for DEL and D(+/-) chimera; and RHD zygosity testing. CONCLUSION Since around 2000, molecular tests for blood groups have been widely offered as a routine service. Many samples are shipped to reference laboratories in the German-speaking countries with the specific request for such testing. The advent of Conformité Européenne (CE)-labeled test kits renders it technically and legally possible, within the specifications of the CE-certification process for in vitro diagnostic devices in the European Union, to replace several blood group serology tasks by genotyping.
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Affiliation(s)
- Willy A Flegel
- Institute of Transfusion Medicine, University Hospital Ulm, Germany.
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Noizat-Pirenne F, Verdier M, Lejealle A, Mercadier A, Bonin P, Peltier-Pujol F, Fialaire-Legendre A, Tournamille C, Bierling P, Ansart-Pirenne H. Weak D phenotypes and transfusion safety: where do we stand in daily practice? Transfusion 2007; 47:1616-20. [PMID: 17725725 DOI: 10.1111/j.1537-2995.2007.01332.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
BACKGROUND Weak D Types 1, 2, and 3 recipients cannot be immunized when exposed to D antigen. Molecular biology is very efficient to type weak D variants but rarely implemented in daily practice. The serologic typing practice of weak D in a Caucasian patient population was analyzed and a transfusion strategy is proposed. STUDY DESIGN AND METHODS Samples typed either ddCcee or ddccEe in routine laboratories were tested with the indirect antiglobulin test (D(u) test). D(u)-positive samples were screened for weak D alleles Types 1, 2, and 3 and further tested with immunoglobulin M (IgM) anti-D reagents, used in a fully automated device. RESULTS A total of 468 of 55,162 samples were found to be ddCcee or ddccEe. Ninety-three expressed weak D after the D(u) test leading to D+ assignment for transfusion. Seventy-three percent of D(u)-positive samples were weak D alleles Type 1, 2, or 3. Almost all weak D Types 1, 2, and 3 were positive with IgM reagents in gel matrix with an automated device. Other variants that could be potentially associated with anti-D alloimmunization, however, were also positive. CONCLUSION Serology is very sensitive to detect weak D Types 1, 2, and 3, but there is no cutoff to distinguish variants of clinical significance. When molecular analysis is not available, it is proposed that a D+ status for blood recipients found to be weak D with a sensitive method be assigned, except for women of childbearing age or younger, because of the remaining possibility to be partial D or other rare weak D who can be immunized.
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Le Maréchal C, Guerry C, Benech C, Burlot L, Cavelier B, Porra V, Delamaire M, Férec C, Chen JM. Identification of 12 novel RHD alleles in western France by denaturing high-performance liquid chromatography analysis. Transfusion 2007. [DOI: 10.1111/j.1537-2995.2007.01200.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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