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Current Immunology Reviews (Discontinued)


ISSN (Print): 1573-3955
ISSN (Online): 1875-631X

Case Report

Warm Reactive Anti-A1 Agglutinin in an A2B individual: A Rare Case with Review of Literature

Author(s): Manish Raturi* and Anuradha Kusum

Volume 16 , Issue 1 , 2020

Page: [52 - 54] Pages: 3

DOI: 10.2174/1573395516999200807162612

Price: $65


The prevalence of the major subgroup of A as A1 in almost 80% of the A group population is a known fact. A2 and the remaining subgroups such as Aend, Am, Ax etc comprise the remaining population, based on erythrocyte agglutinability and various serological reactions. These A subgroups can often result in an ABO typing discrepancy. Anti-A1 antibody often appears as an irregular cold agglutinin in the sera of A2 or A2B individuals who lack the corresponding antigen. Rather notably, the literature suggests that 1% to 8% of A2 and 22% to 35% of A2B individuals possess an allo-anti-A1 in their sera, which reacts at a temperature below 25°C. Although routinely, it does not pose any problem either during or post blood transfusion, however, the literature reports of hemolysis happening in procedures that are performed at lower temperatures, particularly in hypothermic situations. We report herein, a case of a massively bleeding A2B Indian lady after the expulsion of her dead fetus and an underlying uterine fibroid having a warm reactive allo-anti-A1 agglutinin that warranted an urgent blood transfusion management.

Keywords: A2, A2B type, subgroups, anti-A1 lectin, agglutinin, G1PO.

Graphical Abstract
Shastry S, Bhat S. Imbalance in A2; and A2B phenotype frequency of ABO group in South India. Blood Transfus. 2010; 8(4): 267-70.
[PMID: 20967168]
Laura Cooling ABO, H, and Lewis. Blood groups and structurally related antigensRoback JD, editor technical manual, american association of blood banks. 17th ed. Bethseda, Maryland 2011; pp. 363-7.
Ogasawara K, Yabe R, Uchikawa M, et al. Different alleles cause an imbalance in A2 and A2B phenotypes of the ABO blood group. Vox Sang 1998; 74(4): 242-7.
[] [PMID: 9691405]
Das PK, Nair SC, Harris VK, et al. Distribution of ABO and Rh-D blood groups among blood donors in a tertiary care centre in South India. Trop Doct 2001; 31(1): 47-8.
[] [PMID: 11205608]
Klein HG, Anstee DJ. Mollison’s blood transfusion in clinical medicine. 11th ed. Oxford: Blackwell Science Ltd. 2005.
Azarfarin R, Alizadeh A. Management of A2B blood group in a patient for hypothermic cardiopulmonary bypass surgery--a case report. Middle East J Anaesthesiol 2009; 20(1): 101-3.
[PMID: 19266835]
Hosseini-Maaf B, Hellberg A, Rodrigues MJ, Chester MA, Olsson ML. ABO exon and intron analysis in individuals with the AweakB phenotype reveals a novel O1v-A2 hybrid allele that causes four missense mutations in the A transferase. BMC Genet. 2003;4:17.
[] [PMID: 14617382]
McManigal S, Sims KL. Intravascular hemolysis secondary to ABO incompatible platelet products. An underrecognized transfusion reaction. Am J Clin Pathol 1999; 111(2): 202-6.
[] [PMID: 9930141]
Northoff H, Wölpl A, Sugg U, et al. An unusual sample of irregular anti-A1, probably causing an early delayed transfusion reaction. Blut 1986; 52(5): 317-21.
[] [PMID: 3635418]
Milkins C, Berryman J, Cantwell C, et al. British Committee for Standards in Haematology. Guidelines for pre-transfusion compatibility procedures in blood transfusion laboratories. Transfus Med 2013; 23(1): 3-35.
[] [PMID: 23216974]

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