Immunohematology最新文献

{"title":"Effect of cryopreservation on a rare McLeod donor red blood cell concentrate.","authors":"T R Turner,&nbsp;G Clarke,&nbsp;G A Denomme,&nbsp;R Skeate,&nbsp;J P Acker","doi":"10.21307/immunohematology-2021-012","DOIUrl":"https://doi.org/10.21307/immunohematology-2021-012","url":null,"abstract":"<p><p>Units of red blood cell (RBC) concentrates with rare phenotypes are typically not included in method validation studies for cryopreservation processes; rather, they are reserved for patients with rare blood needs. Some rare RBC phenotypes may demonstrate membrane abnormalities, like acanthocytosis as observed for RBCs with the McLeod phenotype, and are specifically banked for these rare attributes; however, the impact that rare RBC phenotypes have on post-thaw quality has not been well studied. To evaluate how a rare RBC phenotype is affected by the cryopreservation process, 4 RBC units, cryopreserved in 1993 using manual methods, were selected for evaluation. These RBCs included one with the McLeod phenotype and three with phenotypes not known to cause significant membrane changes. Post-thaw, an altered deglycerolization protocol, implemented to reduce supernatant glycerol after cryopreservation, was used before processing RBCs on an automated closed system (ACP 215; Haemonetics, Boston, MA) to accommodate the use of a closed system cell processor not available when the RBC units were previously cryopreserved. RBC quality was tested at 24 hours, 7 days, and 14 days post-deglycerolization. Before deglycerolization, an extracted sample from the thawed glycerolized RBC unit was used to obtain genetic material for phenotype confirmation. Genotyping confirmed the McLeod phenotype. When comparing McLeod with non-McLeod units, RBCs from the McLeod donor exhibited acanthocytosis, higher rigidity, and lower morphology scores than RBCs from the non-McLeod units post-deglycerolization. Hemolysis, however, was comparable across all 4 units, meeting regulatory standards. Therefore, McLeod RBCs can withstand cryopreservation, suggesting that units from these donors, glycerolized using older methods, can be deglycerolized using the ACP 215 and stored hypothermically for 14 days. It was also determined that genotyping can be performed on non-leukocyte-reduced cryopreserved RBCs, allowing for confirmation of genetic profiles of donor units banked before the implementation of molecular methods.</p><p><p>Units of red blood cell (RBC) concentrates with rare phenotypes are typically not included in method validation studies for cryopreservation processes; rather, they are reserved for patients with rare blood needs. Some rare RBC phenotypes may demonstrate membrane abnormalities, like acanthocytosis as observed for RBCs with the McLeod phenotype, and are specifically banked for these rare attributes; however, the impact that rare RBC phenotypes have on post-thaw quality has not been well studied. To evaluate how a rare RBC phenotype is affected by the cryopreservation process, 4 RBC units, cryopreserved in 1993 using manual methods, were selected for evaluation. These RBCs included one with the McLeod phenotype and three with phenotypes not known to cause significant membrane changes. Post-thaw, an altered deglycerolization protocol, implemented to reduce supe","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":" ","pages":"78-83"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39106735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Severe perinatal hemolytic disease due to anti-e.","authors":"G Soler-Noda,&nbsp;Y Romero-Díaz,&nbsp;L Orbeal-Aldama,&nbsp;S Aquino-Rojas","doi":"10.21307/immunohematology-2021-011","DOIUrl":"https://doi.org/10.21307/immunohematology-2021-011","url":null,"abstract":"<p><p>Maternal antibody-mediated fetal red blood cell destruction secondary to non-D Rh system antibodies is a significant cause of hemolytic disease of the fetus and newborn. Here, we report a rare case of severe perinatal hemolytic disease associated with maternal antibody to the e antigen. In addition to severe anemia, the infant developed hyperbilirubinemia. Resolution of the infant's anemia and hyperbilirubinemia occurred after treatment with phototherapy, intravenous immunoglobulin, and transfusion.</p><p><p>Maternal antibody-mediated fetal red blood cell destruction secondary to non-D Rh system antibodies is a significant cause of hemolytic disease of the fetus and newborn. Here, we report a rare case of severe perinatal hemolytic disease associated with maternal antibody to the e antigen. In addition to severe anemia, the infant developed hyperbilirubinemia. Resolution of the infant’s anemia and hyperbilirubinemia occurred after treatment with phototherapy, intravenous immunoglobulin, and transfusion.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":" ","pages":"72-77"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39106736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An interesting case of alloanti-M exhibiting typical dosage phenomenon.","authors":"Sheetal Malhotra,&nbsp;Ashish Jain,&nbsp;Sirat Kaur,&nbsp;Alakananda Walia,&nbsp;Lakhvinder Singh,&nbsp;Ratti Ram Sharma","doi":"10.21307/immunohematology-2021-0015","DOIUrl":"https://doi.org/10.21307/immunohematology-2021-0015","url":null,"abstract":"","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":"37 2","pages":"95-96"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10600790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B subgroup detection in a small hospital transfusion service.","authors":"E Elardo,&nbsp;N Elbadri,&nbsp;C Sanchez,&nbsp;V Powell,&nbsp;M Smaris,&nbsp;Y Li,&nbsp;J Jacobson,&nbsp;T Hilbert,&nbsp;T Hamilton,&nbsp;D W Wu","doi":"10.21307/immunohematology-2021-014","DOIUrl":"https://doi.org/10.21307/immunohematology-2021-014","url":null,"abstract":"<p><p>The ABO blood group system includes phenotypes, or subgroups, that differ in the amount of A and B antigens present on the red blood cells (RBCs). These subgroups also differ in the A, B, or H substances present in secretions (for individuals who have the secretor phenotype). B subgroups are very rare and are less frequently reported than A subgroups. Usually, B subgroups are discovered during serologic testing when there is a discrepancy between RBC and serum grouping results. Subgroups of B are usually identified by a reference laboratory using molecular and adsorption-elution methods. This report details a case of a young, healthy, pregnant woman with a B subgroup detected by a small transfusion service using adsorption-elution methods. Serology and genotyping of the <i>ABO</i> gene was performed at a reference laboratory where the serology was consistent with a B subgroup, but no changes were identified in <i>ABO</i> gene sequencing. It is important to correctly identify B subgroups in donors and recipients to help resolve ABO discrepancies and potentially prevent ABO incompatibility in blood transfusion, thus minimizing transfusion reactions.</p><p><p>The ABO blood group system includes phenotypes, or subgroups, that differ in the amount of A and B antigens present on the red blood cells (RBCs). These subgroups also differ in the A, B, or H substances present in secretions (for individuals who have the secretor phenotype). B subgroups are very rare and are less frequently reported than A subgroups. Usually, B subgroups are discovered during serologic testing when there is a discrepancy between RBC and serum grouping results. Subgroups of B are usually identified by a reference laboratory using molecular and adsorption-elution methods. This report details a case of a young, healthy, pregnant woman with a B subgroup detected by a small transfusion service using adsorption-elution methods. Serology and genotyping of the <i>ABO</i> gene was performed at a reference laboratory where the serology was consistent with a B subgroup, but no changes were identified in <i>ABO</i> gene sequencing. It is important to correctly identify B subgroups in donors and recipients to help resolve ABO discrepancies and potentially prevent ABO incompatibility in blood transfusion, thus minimizing transfusion reactions.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":" ","pages":"89-94"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39106737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anti-A₁Le^b: a mind boggler.","authors":"A Gupta,&nbsp;K Chaudhary,&nbsp;S Asati,&nbsp;B Kakkar","doi":"10.21307/immunohematology-2021-010","DOIUrl":"https://doi.org/10.21307/immunohematology-2021-010","url":null,"abstract":"<p><p>The Lewis blood group system is unique because antigens are neither alleles of the same gene nor are they synthesized by red blood cells (RBCs); rather, they are adsorbed onto the RBC membrane from plasma as glycolipids. Antibodies against Lewis antigens are predominantly naturally occurring immunoglobulin (Ig)M type that sometimes react at 37°C and the antihuman globulin phase. Lewis compound antigens, ALe^b and BLe^b, have been described that were confirmed because of the presence of antibodies against them. These compound antigens are the result of an interaction between <i>ABO, H, SE</i>, and <i>LE</i> genes.</p><p><p>The Lewis blood group system is unique because antigens are neither alleles of the same gene nor are they synthesized by red blood cells (RBCs); rather, they are adsorbed onto the RBC membrane from plasma as glycolipids. Antibodies against Lewis antigens are predominantly naturally occurring immunoglobulin (Ig)M type that sometimes react at 37°C and the antihuman globulin phase. Lewis compound antigens, ALe^b and BLe^b, have been described that were confirmed because of the presence of antibodies against them. These compound antigens are the result of an interaction between <i>ABO, H, SE</i>, and <i>LE</i> genes.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":" ","pages":"69-71"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39106733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Statistical model for prediction of ABO hemolytic disease of the fetus and newborn in India.","authors":"D S Patale,&nbsp;T L Lokhande,&nbsp;R K Chaudhary","doi":"10.21307/immunohematology-2021-009","DOIUrl":"https://doi.org/10.21307/immunohematology-2021-009","url":null,"abstract":"<p><p>ABO incompatibility is the most common cause of immune hemolytic disease of the fetus and newborn (HDFN). The American Academy of Pediatrics lists blood group incompatibility as one of the major risk factors for severe hyperbilirubinemia in newborns. We have estimated the risk of ABO HDFN to determine the need for its routine screening. Blood group data from all blood donors who donated in the last 10 years were collected and analyzed. The population prevalence of ABO blood group genes using the phenotype data of blood donors was estimated. This information was further used to calculate an incidence of ABO HDFN requiring intervention in the population. ABO blood group typing was analyzed in 425,743 blood donors. The ABO phenotypes of A, B, O, and AB were 22.48, 36.73, 31.59, and 9.2 percent, respectively. The gene frequencies were 0.1733, 0.2647, and 0.5620 for <i>A</i>, <i>B</i>, and <i>O</i>, respectively. It was estimated that 13.84 percent of group O women would give birth to a non-group O baby and that approximately 2.77 percent of deliveries would likely have ABO HDFN in the study population. In India, the estimated risk of ABO HDFN is 2.9 percent, with a daily 2196 babies at risk of ABO HDFN requiring intervention. This analysis estimates the overall burden of ABO HDFN in the population, which could aid in the decision-making of policymakers, physicians, and community health practitioners to improve neonatal care.</p><p><p>ABO incompatibility is the most common cause of immune hemolytic disease of the fetus and newborn (HDFN). The American Academy of Pediatrics lists blood group incompatibility as one of the major risk factors for severe hyperbilirubinemia in newborns. We have estimated the risk of ABO HDFN to determine the need for its routine screening. Blood group data from all blood donors who donated in the last 10 years were collected and analyzed. The population prevalence of ABO blood group genes using the phenotype data of blood donors was estimated. This information was further used to calculate an incidence of ABO HDFN requiring intervention in the population. ABO blood group typing was analyzed in 425,743 blood donors. The ABO phenotypes of A, B, O, and AB were 22.48, 36.73, 31.59, and 9.2 percent, respectively. The gene frequencies were 0.1733, 0.2647, and 0.5620 for <i>A</i>, <i>B</i>, and <i>O</i>, respectively. It was estimated that 13.84 percent of group O women would give birth to a non–group O baby and that approximately 2.77 percent of deliveries would likely have ABO HDFN in the study population. In India, the estimated risk of ABO HDFN is 2.9 percent, with a daily 2196 babies at risk of ABO HDFN requiring intervention. This analysis estimates the overall burden of ABO HDFN in the population, which could aid in the decision-making of policymakers, physicians, and community health practitioners to improve neonatal care.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":" ","pages":"64-68"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39106738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Ok blood group system: an update.","authors":"J R Storry","doi":"10.21307/immunohematology-2021-004","DOIUrl":"https://doi.org/10.21307/immunohematology-2021-004","url":null,"abstract":"<p><p>This update of the Ok (OK) blood group system (Smart EA, Storry JR. The OK blood group system: a review. Immunohematology 2010;26:124-6) focuses on new information on the role of basigin (BSG), the carrier molecule of the Ok blood group antigens. No further antigens have been identified since the original review. However, the role of BSG in malaria continues to be explored. <b><i>Immunohematology 2021;37:18-19.</i></b></p><p><p>This update of the Ok (OK) blood group system (Smart EA, Storry JR. The OK blood group system: a review. Immunohematology 2010;26:124–6) focuses on new information on the role of basigin (BSG), the carrier molecule of the Ok blood group antigens. No further antigens have been identified since the original review. However, the role of BSG in malaria continues to be explored. <b><i>Immunohematology 2021;37:18–19.</i></b></p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":" ","pages":"18-19"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38960601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acute hemolytic transfusion reaction caused by anti-Yt^a.","authors":"M Raos,&nbsp;N Thornton,&nbsp;M Lukic,&nbsp;B Golubic Cepulic","doi":"10.21307/immunohematology-2021-003","DOIUrl":"https://doi.org/10.21307/immunohematology-2021-003","url":null,"abstract":"<p><p>Many patients with anti-Yt^a receive multiple transfusions of Yt(a+) red blood cells (RBCs) with no ill effects. However, anti-Yt^a has been implicated in hemolytic transfusion reactions. Antibody identification typically determines specificity of antibodies and their clinical significance to justify blood requirements for antigen-negative blood when clinically significant antibodies are involved. Occasionally, specificity of antibody is of variable significance. Variability in clinical significance is a characteristic of anti-Yt^a that may affect the clinical management of such patients. This case reports the outcome of an incompatible transfusion in an 83-year-old female patient with anti-Yt^a, -D, -C, -Le^ab, and -HI who was admitted to the hospital for a severe urinary tract hemorrhage and fever. The patient was transfused with 1 crossmatch-incompatible group A, Yt(a+), D-, C-, E-, S- RBC unit in an emergency medical event. During that time, the patient exhibited chills, shivering, and tachycardia. Decreases in hemoglobin and hematocrit were noted. Laboratory parameters for hemolysis, such as total bilirubin, direct bilirubin, and lactate dehydrogenase, were increased. Based on clinical and laboratory evaluation, it was concluded that the patient had an acute hemolytic transfusion reaction caused by anti-Yt^a. The patient was successfully treated with antipyretics, antihistamines, and corticosteroids. Urinary tract hemorrhaging was stopped. Anemia was additionally improved with parenteral iron supplementation, and further transfusion was not required. <b><i>Immunohematology 2021;37:13-17</i>.</b></p><p><p>Many patients with anti-Yt^a receive multiple transfusions of Yt(a+) red blood cells (RBCs) with no ill effects. However, anti-Yt^a has been implicated in hemolytic transfusion reactions. Antibody identification typically determines specificity of antibodies and their clinical significance to justify blood requirements for antigen-negative blood when clinically significant antibodies are involved. Occasionally, specificity of antibody is of variable significance. Variability in clinical significance is a characteristic of anti-Yt^a that may affect the clinical management of such patients. This case reports the outcome of an incompatible transfusion in an 83-year-old female patient with anti-Yt^a, -D, -C, -Le^ab, and -HI who was admitted to the hospital for a severe urinary tract hemorrhage and fever. The patient was transfused with 1 crossmatch-incompatible group A, Yt(a+), D–, C–, E–, S– RBC unit in an emergency medical event. During that time, the patient exhibited chills, shivering, and tachycardia. Decreases in hemoglobin and hematocrit were noted. Laboratory parameters for hemolysis, such as total bilirubin, direct bilirubin, and lactate dehydrogenase, were increased. Based on clinical and laboratory evaluation, it was con","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":" ","pages":"13-17"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38960598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A fatal case of acute hemolytic transfusion reaction caused by anti-Wr^a: case report and review of the literature.","authors":"A Espinosa,&nbsp;L J Garvik,&nbsp;N Trung Nguyen,&nbsp;B Jacobsen","doi":"10.21307/immunohematology-2021-005","DOIUrl":"https://doi.org/10.21307/immunohematology-2021-005","url":null,"abstract":"<p><p>The red blood cell (RBC) antigen Wr^a is a low-prevalence antigen first described in 1953 by Holman and assigned to the Diego system in 1995. Because of its low prevalence, Wr^a is usually absent on commercial screening RBCs and antibody identification panels. When Wr(a+) screening RBCs are available, the corresponding antibody, anti-Wr^a, is often found in sera from healthy individuals, patients, and pregnant women. Anti-Wr^a can cause both hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. We describe a fatal acute hemolytic transfusion reaction caused by anti-Wr^a in a patient with no other RBC alloantibodies. Serologic investigation showed that one of the RBC units the patient received was Wr(a+). <b><i>Immunohematology 2021;37:20-24</i>.</b></p><p><p>The red blood cell (RBC) antigen Wr^a is a low-prevalence antigen first described in 1953 by Holman and assigned to the Diego system in 1995. Because of its low prevalence, Wr^a is usually absent on commercial screening RBCs and antibody identification panels. When Wr(a+) screening RBCs are available, the corresponding antibody, anti-Wr^a, is often found in sera from healthy individuals, patients, and pregnant women. Anti-Wr^a can cause both hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. We describe a fatal acute hemolytic transfusion reaction caused by anti-Wr^a in a patient with no other RBC alloantibodies. Serologic investigation showed that one of the RBC units the patient received was Wr(a+). <b><i>Immunohematology 2021;37:20–24</i>.</b></p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":" ","pages":"20-24"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38960599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transfusion support during childbirth for a woman with anti-U and the <i>RHD*weak D type 4.0</i> allele.","authors":"Q Yin,&nbsp;K Srivastava,&nbsp;D G Brust,&nbsp;W A Flegel","doi":"10.21307/immunohematology-2021-001","DOIUrl":"https://doi.org/10.21307/immunohematology-2021-001","url":null,"abstract":"<p><p>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 <i>RHD*weak D type 4.0</i> 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 <i>RHD*weak D type 4.0</i> allele was determined by <i>RHD</i> 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 <i>RHD*weak D type 4.0</i> 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 <i>RHD</i> genotyping is early in a pregnancy. <b><i>Immunohematology 2021;37:1-4</i></b> .</p><p><p>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 <i>RHD*weak D type 4.0</i> 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 <i>RHD*weak D type 4.0</i> allele was determined by <i>RHD</i> 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 <i>RHD*weak D type 4.0</i> 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 <i>RHD</i> genotyping is early in a pregnancy. <b><i>Immunohematology 2021;37:1–4</i></b> .</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":" ","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8108908/pdf/nihms-1696036.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38971038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}