Report on Unexpected Antibodies Detected Exclusively in the Serum / 대한수혈학회지

In 2023, an 81-year-old woman requested a preliminary red blood cell transfusion during pancreatic cancer surgery, and antibody screening was performed using automated blood typing equipment. The antibody screening test results were negative when plasma was used as the sample but positive when the serum was used instead. The 4℃ test was positive when using the enzyme method but negative at warm temperatures. An unknown antibody was identified using a commercial antibody identification test (Bio-Rad, CA, USA). A clinically insignificant cold antibody was detected only in the serum samples, and the negative blood was ultimately released following the third stage of cross-matching using anti-human globulin.

Rare ABO Allele Encoding Glycosyltransferase with Dual Specificity Found in a Cambodian Individual with the A 2 B Phenotype / 대한수혈학회지

Cis-AB and B(A) alleles encode an ABO enzyme with dual A and B glycosyltransferase activity. Although globally rare, the cis-AB phenotype is found relatively often in Korean, Japanese, and Chinese populations. Cases of the B(A) allele have been reported mostly in the Chinese population. Forward typing performed in a Cambodian woman with an ABO discrepancy demonstrated a strong reaction with anti-A and anti-B reagents, while there was no reaction with lectin anti-A 1. The anti-A 1 antibody was detected in reverse typing. Through ABO gene sequence analyses of exons 6 and 7, one of the alleles was identified as ABO*B.01. In contrast, the other allele harboring a c.803G＞C substitution was either ABO*cisAB.05 or ABO*BA.06 allele. The ABO*cisAB.05 and ABO*BA.06 alleles remain indistinguishable despite routine serological testing and ABO genotyping. To the best of the author’s knowledge, this is the first case report of these variants discovered in a Cambodian individual residing in Korea.

A Case of Partial D Type VI-3 Confirmed by RHD Genotyping

Weak D and partial D result in quantitative and qualitative changes in RhD protein expression respectively. It is difficult to discriminate weak D from partial D by serological tests alone. RHD genotyping is a useful method that complements serological results. A 64-year-old woman visited our hospital for microvascular decompression surgery. Her blood type was O, D negative by manual tube test and as per auto analyzer results (QWALYS-3 system; DIAGAST, France). Weak D and partial D tests were performed by using two different monoclonal anti-D reagents (Bioscot; Merck Millipore, UK; Bioclone; Ortho Clinical Diagnostics, USA) and a panel of nine monoclonal antibodies, including anti-D IgM and IgG (D-Screen; DIAGAST, France). However, these serological tests could not confirm the subtype of partial D. Therefore, sequencing of RHD exon 1 to 10 was additionally performed for the patient and the case was revealed to be partial DVI type 3.

Weak D Type 102 Found in a Family Study: The First Case in Korea / 대한수혈학회지

Weak D type 102 allele (RHD*01W.102) carrying a missense variant (c.73A＞T, p.Ile25Phe) in exon 1 of the RHD has not been reported in Koreans to date. This is the first report of the weak D type 102 allele in the Korean population. The proposita, a 35-year-old woman, showed a serological weak D phenotype in routine RhD typing. Sequencing of all 10 RHD exons and zygosity testing targeting the hybrid Rhesus box revealed this proposita to harbor the weak D type 102 allele, as well as an RHD deletion (RHD*01W.102/RHD*01N.01). Family studies showed that the weak D type 102 allele was also present in her father and older brother (both assumed to be RHD*01W.102/RHD*01) but not in her mother and oldest brother (both assumed to be RHD*01/RHD*01N.01). In silico analysis of the replacement of isoleucine by phenylalanine at position 25 was done with PolyPhen-2, SIFT, and PROVEAN. While PolyPhen-2 predicted the variant as benign, SIFT and PROVEAN predicted it as damaging and deleterious, respectively, suggesting RHD c.73A>T (I25F) as the cause of serologic weak D phenotype. This patient should be treated as D-negative, when transfusion is needed.

Rare ABO Allele Encoding Glycosyltransferase with Dual Specificity Found in a Cambodian Individual with the A 2 B Phenotype / 대한수혈학회지

Cis-AB and B(A) alleles encode an ABO enzyme with dual A and B glycosyltransferase activity. Although globally rare, the cis-AB phenotype is found relatively often in Korean, Japanese, and Chinese populations. Cases of the B(A) allele have been reported mostly in the Chinese population. Forward typing performed in a Cambodian woman with an ABO discrepancy demonstrated a strong reaction with anti-A and anti-B reagents, while there was no reaction with lectin anti-A 1. The anti-A 1 antibody was detected in reverse typing. Through ABO gene sequence analyses of exons 6 and 7, one of the alleles was identified as ABO*B.01. In contrast, the other allele harboring a c.803G＞C substitution was either ABO*cisAB.05 or ABO*BA.06 allele. The ABO*cisAB.05 and ABO*BA.06 alleles remain indistinguishable despite routine serological testing and ABO genotyping. To the best of the author’s knowledge, this is the first case report of these variants discovered in a Cambodian individual residing in Korea.

A Case of Partial D Type VI-3 Confirmed by RHD Genotyping

Weak D and partial D result in quantitative and qualitative changes in RhD protein expression respectively. It is difficult to discriminate weak D from partial D by serological tests alone. RHD genotyping is a useful method that complements serological results. A 64-year-old woman visited our hospital for microvascular decompression surgery. Her blood type was O, D negative by manual tube test and as per auto analyzer results (QWALYS-3 system; DIAGAST, France). Weak D and partial D tests were performed by using two different monoclonal anti-D reagents (Bioscot; Merck Millipore, UK; Bioclone; Ortho Clinical Diagnostics, USA) and a panel of nine monoclonal antibodies, including anti-D IgM and IgG (D-Screen; DIAGAST, France). However, these serological tests could not confirm the subtype of partial D. Therefore, sequencing of RHD exon 1 to 10 was additionally performed for the patient and the case was revealed to be partial DVI type 3.

Extended Red Blood Cell Phenotype Matching Is Dependent on Ethnicity and Specificity of RBC Alloantibodies

No abstract available.

Evaluation of Analytical Performance of an Automated Glycated Hemoglobin Analyzer, HLC-723 G11

ABO*B3.01 Found in the A1B3 Phenotype Showing ABO Discrepancy: The First Case in Korea / 대한수혈학회지

B₃ is a rare finding, but it is most common in the B subgroup, which been reported as being 0.025% of the total B group in Koreans. ABO*B3.01 is a specific allele for B₃, a missense mutation with a substituted thymine from cytosine of the 1,054th nucleotide of the ABO*B.01 allele, but rather unexpectedly, it has not been reported in Koreans. We report here the first Korean case of the serological A₁B₃ phenotype with ABO*B3.01, which was confirmed by sequencing of exons 6 and 7 of the ABO gene, found in a pregnant woman.

Alloantibodies to High-Incidence Antigen: Review of Cases and Transfusion Experiences in Korea / 대한수혈학회지

Antibodies to high-incidence red blood cell antigens should be considered if panagglutination reactions are noted in all panel cells, and negative reactions to autologous red blood cells are detected on antibody screening and identification tests. In Korea, most of those antibodies are identified through international reference laboratories. To prevent a hemolytic transfusion reaction, antigen-negative red cells should be provided for those patients who have antibodies to red cell antigens. However, this is nearly impossible when the antibody has specificity to high-incidence red cell antigen. In those cases, transfusion of autologous blood, cryopreserved rare blood and the least incompatible blood components can be considered. In the case of surgery, acute normovolemic hemodilution or intraoperative blood salvage can also be considered. For the patients who have antibodies to high-incidence red cell antigens, it should be discussed to set up a national reference laboratory to quickly identify antibody specificities, and to consider establishing rare blood donor registry and frozen rare blood storage/supply system. This article reviews characteristics of antibodies to high-incidence antigens found in Koreans and also the transfusion experiences of those patients based on literature.

Usefulness of Chromosomal Microarray in Hematologic Malignancies: A Case of Aggressive NK-cell Leukemia with 1q Abnormality

A variety of clonal cytogenetic abnormalities have been reported in aggressive natural killer (NK)-cell lymphoma and leukemia. Recent chromosomal microarray studies have shown both gain and loss of 1q and loss of 7p as recurrent abnormalities in aggressive NK-cell leukemia. Here, we report a case of aggressive NK-cell leukemia with complex chromosomal gains and losses, as confirmed by chromosomal microarray analysis. The patient showed an aggressive clinical course, which was complicated by hemophagocytic lymphohistiocytosis. Conventional cytogenetic analysis revealed trisomy 3 and 1q gain only. However, chromosomal microarray analysis detected an additional gain of 1q21.1–q24.2 and a loss of 1q24.2–q31.3. These abnormal lesions might play a role in the pathogenesis of aggressive NK-cell leukemia by inactivating tumor suppressor genes or by activating oncogenes. These results suggest that chromosomal microarray analysis may be used to provide further genetic information for patients with hematological malignancies, including aggressive NK-cell leukemia.

Quality Assurance of Diagnostic Immunologic Tests for Screening of Transfusion-Transmissible Infections at Korean Blood Centers / 대한수혈학회지

The Korean government previously established a national blood policy and national blood system based on basic and essential legislation. This achievement was the result of collaborative efforts between the Korean Centers for Disease Control and Prevention, the Korean Society of Blood Transfusion, the Korean Society for Laboratory Medicine, the Laboratory Medicine Foundation, and/or the Korean Association of External Quality Assessment Service. To ensure a safe and effective transfusion, a comprehensive quality assurance (QA) system to assess every process from donor selection to transfusion is mandatory. From a blood safety perspective, selection of appropriate donor blood screening tests for transfusion-transmissible infections (TTI) and the QA program is of great importance. In this article, we review legislation regarding the national blood policy and national blood system as well as the selection logic regarding diagnostic immunologic tests for TTI and quality assurance efforts for TTI of each blood center.

A Case of Hemolytic Disease of the Fetus and Newborn due to Anti-S Antibody: The First Case in Korea / 대한수혈학회지

A full term male infant was admitted to the neonatal intensive care unit due to jaundice and mild hemolytic anemia within the first 24 hours of his life. The total serum bilirubin level was 11.2 mg/dL at 24 hours of age. The patient was RhD positive and blood group A, and his mother was RhD positive and blood group B. The direct and indirect antiglobulin tests of the infant were all positive. On antibody screening and identification tests, anti-S antibodies were identified from both the infant and mother. The RBC phenotyping for S antigen revealed positive for infant and negative for mother. This report documents the first case of hemolytic disease of the fetus and newborn due to the anti-S antibody in Korea.