ImmunohematologyPub Date : 2025-07-08Print Date: 2025-06-01DOI: 10.2478/immunohematology-2025-008
Janis R Hamilton, Christine Lomas-Francis, Sandra J Nance
{"title":"Investigation of unexplained reactivity: antibody of unknown specificity (AUS).","authors":"Janis R Hamilton, Christine Lomas-Francis, Sandra J Nance","doi":"10.2478/immunohematology-2025-008","DOIUrl":"https://doi.org/10.2478/immunohematology-2025-008","url":null,"abstract":"<p><p>When antibody screening results are positive in a patient\"s sample, the next step is to identify the specificity of the antibody and plan for transfusion or treatment needs. Most often, the antibody can be identified at the transfusing facility; samples that are not resolved may be referred to an immunohematology reference laboratory. A portion of these referred samples may still not be resolved, and the antibodies in these cases have been termed \"antibodies of unidentified or undetermined specificity\". In this publication, we selected the term \"unknown\" for such antibodies. Local medical staff should be involved in the clinical management and transfusion recommendations for these patients. The flow charts described in this article are designed to guide the serologist through steps that may result in a defined antibody specificity, or they may not resolve the specificity, and thus, the antibody remains an \"antibody of unknown specificity\".</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":"41 2","pages":"49-53"},"PeriodicalIF":0.0,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144591161","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}
ImmunohematologyPub Date : 2025-07-08Print Date: 2025-06-01DOI: 10.2478/immunohematology-2025-007
Glenn Ramsey
{"title":"The Rh blood group system: RHD update.","authors":"Glenn Ramsey","doi":"10.2478/immunohematology-2025-007","DOIUrl":"https://doi.org/10.2478/immunohematology-2025-007","url":null,"abstract":"<p><p>The Rh blood group system was last reviewed in <i>Immunohematology</i> in 2010 (Chou ST, Westhoff CM. The Rh and RhAG blood group systems. Immunohematology 2010;26:178-86). This update focuses on RHD, RhD structure, alterations in D expression, anti-D alloimmunization, and applications of RHD genotyping for weak and discrepant D phenotypes; identification of RHD genotypes that encode partial D phenotypes; and prevention and management of anti-D in pregnancy. Updates to the RHAG system and to RHCE and its encoded antigens are in recent or upcoming publications of <i>Immunohematology</i>, respectively.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":"41 2","pages":"31-48"},"PeriodicalIF":0.0,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144591162","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}
ImmunohematologyPub Date : 2025-07-08Print Date: 2025-06-01DOI: 10.2478/immunohematology-2025-009
Beth M Meyer
{"title":"The utility of an acid elution when a direct antiglobulin test is positive due to complement alone.","authors":"Beth M Meyer","doi":"10.2478/immunohematology-2025-009","DOIUrl":"https://doi.org/10.2478/immunohematology-2025-009","url":null,"abstract":"<p><p>Acid elutions are intended to recover IgG antibodies from the red blood cell (RBC) surface. Eluates from samples that are direct antiglobulin test (DAT) positive with complement (C3) only would be expected to be negative. However, elution studies performed on RBCs that are DAT positive with C3 only can produce clinically significant results. Identifying how often clinically relevant information is obtained when elutions are performed on samples DAT positive with C3 alone would aid in developing guidelines for elution performance on these samples and reducing performance of eluates on such samples with clinically insignificant results. Patient samples that are DAT positive with C3 only submitted over an 11.5-month period at the American Red Cross' Immunohematology Reference Laboratory locations were identified. The eluate result, serum result, transfusion history, and patient diagnosis were captured and analyzed. In total, 1171 samples that were DAT positive with C3 only were identified and, of those, 321 (27%) samples had an elution performed. A nonreactive eluate was the most common result. Alloantibodies were identified in 19 (6%) eluates. Panagglutination/autoantibodies was identified in 71 (22%) eluates. Informative eluates were identified as those eluates showing any alloantibody, regardless of serum results, or panagglutination/autoantibody present in the eluate but not concurrently present in the serum (n = 30,9%). Guidelines based on recent transfusion history, indicators of active hemolysis, and autoimmune reactivity concurrently in the serum should be implemented to identify clinically significant information and to reduce the number of uninformative elutions performed.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":"41 2","pages":"54-60"},"PeriodicalIF":0.0,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144591163","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}
ImmunohematologyPub Date : 2025-03-26Print Date: 2025-03-01DOI: 10.2478/immunohematology-2025-003
Trileeshiya I Withanawasam, Nashma Sainudeen
{"title":"Prevalence and clinical implications of unexpected red blood cell antibodies in a tertiary care hospital in Sri Lanka.","authors":"Trileeshiya I Withanawasam, Nashma Sainudeen","doi":"10.2478/immunohematology-2025-003","DOIUrl":"10.2478/immunohematology-2025-003","url":null,"abstract":"<p><p>Unexpected red blood cell (RBC) alloantibodies can lead to hemolytic transfusion reactions and hemolytic disease of the fetus and newborn (HDFN). Screening for these antibodies is essential to ensure transfusion safety and improve patient care. Prevalence and frequency of unexpected antibodies vary among populations, influenced by genetic and demographic factors. This study addresses the gap in data specific to University Hospital, General Sir John Kotelawala Defence University. A retrospective analysis was performed on 20,212 patients (40.74% pregnant women and 59.25% transfusion recipients) from November 2019 to August 2024, assessing the prevalence, distribution, and clinical relevance of RBC alloantibodies. The study found that 0.80 percent of patients were alloimmunized and 28.87 percent of the antibodies were clinically significant. Common antibodies included anti-Le<sup>b</sup> (27.27%) and anti-Lea (19.25%); anti-D was the most frequent among Rh antibodies. A significantly higher proportion of pregnant women were alloimmunized compared with transfusion recipients (<i>p</i> < 0.000). Among D- pregnant women, 5.45 percent were alloimmunized, mainly with anti-D. HDFN was identified with either maternal anti-D or anti-E. These findings emphasize the need for early antibody detection and monitoring to enhance transfusion safety, suggesting policy improvements for antibody screening in transfusion and antenatal care in Sri Lanka.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":"41 1","pages":"4-10"},"PeriodicalIF":0.0,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143718588","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}
ImmunohematologyPub Date : 2025-03-26Print Date: 2025-03-01DOI: 10.2478/immunohematology-2025-0004
Bushra Moiz, Muhammad Hasan, Muhammad Salman, Bhawna Kumari, Emily Black, Yew-Wah Liew
{"title":"Anti-LW masquerading as anti-D in a D+ patient.","authors":"Bushra Moiz, Muhammad Hasan, Muhammad Salman, Bhawna Kumari, Emily Black, Yew-Wah Liew","doi":"10.2478/immunohematology-2025-0004","DOIUrl":"10.2478/immunohematology-2025-0004","url":null,"abstract":"<p><p>LW<sup>a</sup>, LW<sup>ab</sup>, LW<sup>b</sup>, and LWEM are the four main antigens of the Landsteiner-Weiner (LW) blood group system. LW expression may be weakened during pregnancy and immune dysregulation, with the subsequent appearance of anti-LW. Here, we describe a case of an elderly male patient in whom transfusion of red blood cells (RBCs) became challenging because of the presence of anti-LW. A 61-year-old male patient presented with shortness of breath and a hemoglobin level of 7.0 g/dL, requiring RBC transfusions. Serologic workup of his blood sample showed his RBCs to be group A, D+, but his serum was incompatible with several group A, D+ donor RBC units. Antibody screening showed preferential reactivity with D+ panel RBCs that was abolished when using 0.2 M dithiothreitol-treated RBCs. The patient's serum did not react with known RBCs of Rh<sub>null</sub> and LW(a-) phenotypes but reacted strongly with D+ and D- cord RBCs. The patient's sample was genotyped as <i>LW*A/A</i> (c.299A), consistent with the LW(a+b-) phenotype. Subsequent bone marrow examination showed B-lymphoproliferative disorder. The patient required RBC transfusion support because of his underlying disease. Transfusion of group A, D- RBCs was uneventful. The expression of LW in this patient was possibly weakened by his underlying disease, leading to the development of anti-LW. No complications were seen after multiple transfusions of group A, D- RBC units.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":"41 1","pages":"11-16"},"PeriodicalIF":0.0,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143718536","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}
ImmunohematologyPub Date : 2025-03-26Print Date: 2025-03-01DOI: 10.2478/immunohematology-2025-005
Lilian Castilho
{"title":"An update on the LAN blood group system.","authors":"Lilian Castilho","doi":"10.2478/immunohematology-2025-005","DOIUrl":"10.2478/immunohematology-2025-005","url":null,"abstract":"<p><p>This update on the LAN blood group system (Peyrard T. A review of the Lan blood group system. Immunohematology 2013; 29:131-5) reports new <i>ABCB6</i> alleles encoding Lan- and Lan(+<sup>wk</sup>) phenotypes and new functional aspects of the ABCB6 glycoprotein. The L AN blood group system (International Society of Blood Transfusion system 33) consists of one antigen: Lan.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":"41 1","pages":"17-19"},"PeriodicalIF":0.0,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143718990","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}
ImmunohematologyPub Date : 2025-03-26Print Date: 2025-03-01DOI: 10.2478/immunohematology-2025-002
Louise A Tilley
{"title":"An update on the RHAG blood group system.","authors":"Louise A Tilley","doi":"10.2478/immunohematology-2025-002","DOIUrl":"10.2478/immunohematology-2025-002","url":null,"abstract":"<p><p>This update on the RHAG blood group system (ISBT 030) (Chou ST, Westhoff CM. The Rh and RhAG blood group systems. Immunohematology 2010;26:178-86) reports the addition of three new low-prevalence antigens carried on the Rh-associated glycoprotein (RhAG). Kg (previously 700045; now RHAG5) has been demonstrated to be antithetical to the previously described high-prevalence DSLK (RHAG3). Two further low-prevalence antigens (RHAG6 and RHAG7) are described, both resulting from rare missense <i>RHAG</i> mutations encoding amino acid changes predicted to be externally located. All three new low-prevalence antigens have been implicated in hemolytic disease of the fetus and newborn. The RHAG system now comprises six antigens, two of high prevalence and four of low prevalence, including one antithetical pair. RHAG4 has been made obsolete.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":"41 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143718434","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}
ImmunohematologyPub Date : 2024-12-31Print Date: 2024-12-01DOI: 10.2478/immunohematology-2024-022
Crystal Theiler, Christine Lomas-Francis, Sunitha Vege, Marie-Claire Chevrier, Gabriel André Leiva-Torres, Margaret A Keller, Katherine Kaherl, Trina Coppolino, Susan T Johnson
{"title":"Weak and partial D phenotyping: a comparison study between molecular and serologic results.","authors":"Crystal Theiler, Christine Lomas-Francis, Sunitha Vege, Marie-Claire Chevrier, Gabriel André Leiva-Torres, Margaret A Keller, Katherine Kaherl, Trina Coppolino, Susan T Johnson","doi":"10.2478/immunohematology-2024-022","DOIUrl":"10.2478/immunohematology-2024-022","url":null,"abstract":"<p><p>Variant D antigens can cause variable serologic results when typing with Anti-D reagents. There is limited information regarding the ability of Anti-D reagents to differentiate between D variants defined by <i>RHD</i> genotyping. This study was performed to determine if a panel of 20 U.S. Food and Drug Administration-licensed Anti-D reagents can identify molecularly defined D variants. Red blood cells from 119 donors carrying variant <i>RHD</i> alleles were tested at immediate spin (IS) and/or by the indirect antiglobuin test (IAT) using conventional test tube and/or column agglutination technology. Reaction strength at IS and IAT was reviewed to determine whether a pattern of reactivity could be correlated with a specific D variant. Agglutination results from each sample with each Anti-D reagent were combined to assess overall reactivity. The sample set consisted of 21 D variants, based on prior <i>RHD</i> genotyping. Of these variants, nine categories had three or more samples used for analysis (<i>N</i> = 102); 25 <i>RHD*01W.1,</i> 15 <i>RHD*01W.2,</i> 14 <i>RHD*01W.3,</i> 17 <i>RHD*09.01,</i> 14 <i>RHD*09.03,</i> 4 <i>RHD*01W.4,</i> 23 <i>RHD*07,</i> 4 <i>RHD*10.05,</i> and 6 reference allele <i>RHD*01.</i> As expected, IS showed more negative or weak reactions, and IAT produced more positive reactions with 3+/4+ agglutination strength. <i>RHD*01W.3</i> samples showed strongest reactivity at IS and IAT. Greatest variation in reactivity was observed with <i>RHD*01W.2,</i> showing weakest overall reactivity at IS. All weak D types had at least one sample that yielded a negative result and one sample with 4+ agglutination at IS. Although there were general patterns of reactivity for each variant tested, no one pattern defined all samples carrying the same <i>RHD</i> allele. This study demonstrated that even with 20 different Anti-D reagents, serologic testing alone is insufficient to define weak or partial D types, characterize the risk for alloanti-D, or determine candidacy for Rh immune globulin. The results illustrate how multiple Anti-D reagents can be used to identify samples that should be reflexed to molecular testing.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":"40 4","pages":"159-165"},"PeriodicalIF":0.0,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142909477","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}
ImmunohematologyPub Date : 2024-12-31Print Date: 2024-12-01DOI: 10.2478/immunohematology-2024-021
Thomas Larsen Titze, Norunn Ulvahaug, Magnus Moksnes, Nanna Skeie, Vanja Karamatic Crew, Çiğdem Akalın Akkök, Nicole Thornton
{"title":"Transient suppression of high-prevalence Kell blood group antigens and concomitant development of a Kell-related antibody that appears to recognize a high-prevalence Kell antigen not previously defined.","authors":"Thomas Larsen Titze, Norunn Ulvahaug, Magnus Moksnes, Nanna Skeie, Vanja Karamatic Crew, Çiğdem Akalın Akkök, Nicole Thornton","doi":"10.2478/immunohematology-2024-021","DOIUrl":"10.2478/immunohematology-2024-021","url":null,"abstract":"<p><p>A previously healthy 32-year-old male patient was admitted to hospital with malaise, dyspnea, anemia, thrombocytopenia, and leukopenia. Anemia and thrombocytopenia worsened during the third week. Considering the possible need for transfusion, routine ABO and D typing and an antibody detection test were performed. Antibody detection test was positive, necessitating fur ther immunohematologic investigation that revealed an antibody with Kell-related specificity and suppression/alteration of several high-prevalence Kell blood group system antigens. Autocontrols and direct antiglobulin tests (DATs) were negative in several samples during the disease course. Sequencing of the patient's <i>KEL</i> and <i>XK</i> genes did not reveal any mutations. Initial tentative diagnosis was myeloid neoplasm based on dyserythropoiesis in the bone marrow smear and no obvious biochemical signs of hemolysis. Azacitidine treatment was initiated, accordingly, but had to be interrupted when the patient's hemoglobin (Hb) dropped to 4.6 g/dL in 3 days, and he experienced more severe anemia symptoms (fatigue, nausea, and heart palpitations). Platelet concentrates, and 3 very rare Kell<sub>null</sub> packed RBC concentrates, imported from abroad, were transfused. However, no increase in Hb was achieved. Platelet autoantibodies were not detected. Suspecting an autoimmune etiology, intravenous immunoglobulin and high-dose glucocorticoids were given. The patient responded to the latter treatment; he felt much better and regained his daily activity, and his Hb value and platelet count normalized on day 45. The steroid dose was tapered during the next 6 months until it was discontinued. His RBCs had normal Kell antigen expression, and the antibody was undetectable on day 105. Therefore, we concluded that an autoimmune etiology was the most plausible cause for the patient's condition despite a negative DAT. The immunohematologic investigation showed disease-related transient loss and/or alteration of several Kell system high-prevalence antigens and a Kell-related antibody that appeared to recognize a unique high-prevalence Kell antigen with a not-yet fully defined epitope.</p>","PeriodicalId":13357,"journal":{"name":"Immunohematology","volume":"40 4","pages":"153-158"},"PeriodicalIF":0.0,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142909561","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}