Bombay Blood Group: A Report of Two Cases.

Timely detection of rare blood groups can be lifesaving, as individuals with these groups can only receive blood products from donors within the same group. The Bombay blood group is characterized by the absence of A, B, and H antigens on the surface of RBCs and can be easily missed in routine blood grouping if only forward grouping is performed. In reverse grouping, it is necessary to test the patient's serum with pooled O cells to differentiate between the O and Bombay blood groups. Further workup is conducted by testing the patient's red cells with anti-H lectin (antisera), where the absence of an agglutination reaction suggests the Bombay phenotype. In blood group O testing, the patient's blood serum mixed with pooled O cells yields no agglutination reaction in reverse typing, whereas testing RBCs with anti-H lectin results in a strong agglutination reaction, as H-antigen is present at its highest concentration in these individuals. Correct diagnosis of such rare blood types can save patients' lives as well as prevent the consequences of a wrong blood transfusion. Here we present two cases that were diagnosed as having the Bombay phenotype on blood group testing in our blood bank. Both were initially misdiagnosed as blood group O by an outside laboratory. Correct diagnosis of rare blood groups in blood banks is imperative, as a misdiagnosis can result in fatal outcomes.

[Rare red blood group discovered by a blood group discrepancy: a case report]. / Découverte d'un phénotype érythrocytaire rare suite à une difficulté de groupage : à propos d'un cas.

ABO typing is essential for preventing ABO incompatibility transfusion reactions. Discrepancy exists when reactions in forward grouping do not match with reverse grouping. Any discrepancies reported should be investigated so that correct blood group is reported minimizing the chances of transfusion reaction. The most common causes of ABO discrepancy are cold autoantibodies and missing serum reactivity. We report a rare alloantibody anti-PP1Pk discovered during the resolution of a grouping difficulty with a positive control. Anti-PP1Pk is associated with hemolytic transfusion reactions. In our observation, we were faced with transfusional impasse because of the unavailability of a national rare blood bank or a compatible donor on the registry of individuals with a rare blood phenotype.

Bombay Blood Group Phenotype Misdiagnosed As O Phenotype: A Case Report.

Bombay blood group is a rare type that was initially identified in the city of Bombay, India. It is characterized by the presence of serum antibodies anti-A, anti-B, and anti-H, which can cause agglutination in all blood groups within the ABO system. The clinical importance of the Bombay blood group lies in its inability to receive transfusions from other blood groups. In this case report, we present a case of a young male who was initially misdiagnosed as having an O phenotype, resulting in a hemolytic transfusion reaction. This case highlights the diagnostic and therapeutic challenges associated with rare blood phenotypes.

Challenges in the transfusion management of a 15-month-old pediatric patient with Bombay blood group phenotype.

Bombay blood group phenotype is often mistyped as O group which can lead to hemolytic transfusion reactions. There are a very few case reports of Bombay blood group phenotype in pediatric age group. Herein, we report an interesting case of Bombay blood group phenotype in a fifteen-month-old pediatric patient who presented with features of raised intracranial pressure and required an emergency surgery. The Bombay blood group was detected on detailed immunohematology work up which was further confirmed by molecular genotyping. The challenges faced in developing countries for transfusion management of such a case have been discussed.

Rare Blood Groups in ABO, Rh, Kell Systems - Biological and Clinical Significance.

Background: The frequency of ABO, Rh and Kell blood group antigens differs among populations of different ethnic ancestry. There are low-frequency antigens (<1%) and high-frequency antigens (>90%). A rare blood group is defined as the absence of a high-frequency antigen in the general population, as well as absence of multiple frequent antigens within a single or multiple blood group systems. Aim: To perform red blood cell typing and to calculate the antigen and phenotype frequencies, in order to identify rare blood group donors within the clinically most important АВО, Rh and Kell systems. Material and Methods: АВО, Rh (D, C, E, c, e) and Kell (K) antigen typing was performed using specific monoclonal sera and microplate technique, while Cellano (k) typing was performed with a monoclonal anti-k, antihuman globulin and column agglutination technique. Weak ABO subgroups were determined using the absorption elution method or molecular genotyping (PCR-SSP). Results: ABO antigen frequency is: A (40.89%), O (34.22%), B (16.97%), AB (7.92%) and weak ABO subgroups (0, 009 %). The established genotypes were AxO1 (0, 0026%) and AxB (0, 001%). Rh antigen frequency is: D (85.79%), C (71.7%), c (76.0%), E (26.0%) and е (97.95%). The most common Rh pheno-type is the DCcee (32.7%) while the rarest phenotype is the DCCEE phenotype (0. 003%). The prevalence of K and k antigen is 7.5% and 99.94%, respectively. The frequency of the rare phenotype K+k- is 0.06%. Conclusion: Large scale phenotyping of blood group antigens enables the identification of blood donors with rare blood groups for patients with rare phenotypes or with antibodies to high-frequency antigens and to frequent antigens within one or more blood group systems.

Application of Blood Group Genotyping by Next-Generation Sequencing in Various Immunohaematology Cases.

Background: Next-generation sequencing (NGS) technology has been recently introduced into blood group genotyping; however, there are few studies using NGS-based blood group genotyping in real-world clinical settings. In this study, we applied NGS-based blood group genotyping into various immunohaematology cases encountered in routine clinical practice. Methods: This study included 4 immunohaematology cases: ABO subgroup, ABO chimerism, antibody to a high-frequency antigen (HFA), and anti-CD47 interference. We designed a hybridization capture-based NGS panel targeting 39 blood group-related genes and applied it to the 4 cases. Results: NGS analysis revealed a novel intronic variant (NM_020469.3:c.29-10T>G) in a patient with an Ael phenotype and detected a small fraction of ABO*A1.02 (approximately 3-6%) coexisting with the major genotype ABO*B.01/O.01.02 in dizygotic twins. In addition, NGS analysis found a homozygous stop-gain variant (NM_004827.3:c.376C>T, p.Gln126*; ABCG2*01N.01) in a patient with an antibody to an HFA; consequently, this patient's phenotype was predicted as Jr(a-). Lastly, blood group phenotypes predicted by NGS were concordant with those determined by serology in 2 patients treated with anti-CD47 drugs. Conclusion: NGS-based blood group genotyping can be used for identifying ABO subgroup alleles, low levels of blood group chimerism, and antibodies to HFAs. Furthermore, it can be applied to extended blood group antigen matching for patients treated with anti-CD47 drugs.

Molecular genotyping of Indian blood group antigens amongst regular voluntary blood donors of Surat city, Gujarat, India.

BACKGROUND: There is paucity of data related to the prevalence of the rare blood group antigens amongst South Gujarat blood donor population due to unavailability and high cost of antisera. Therefore it is difficult to screen donors for such rare antigens by gold standard haemagglutination assay. The single nucleotide polymorphism (SNPs) of Ina and Inb antigens is the base of the PCR based detection methods that help to detect these alleles in regular voluntary blood donors. MATERIALS & METHODS: Blood samples of 200 unrelated regular voluntary blood donors wee collected. DNA was extracted using phenol-chloroform method and genotyped for Indian (Ina/IN*01, Inb/IN*02) blood group alleles by Sequence Specific PCR. Ina antigen positivity was confirmed by serology test. RESULTS: Four donors were found heterozygous for Ina antigen i.e. In (a + b+) by SS-PCR and their Ina positivity were confirmed by in-house polyclonal Anti-Ina reagent. SS-PCR was standardized using known heterozygous sample of a blood donor. The frequency of Ina antigen (2.0 %) was higher than Caucasians, lower than Iranians and Arabs while comparable to those reported among Indians of Mumbai city. CONCLUSION: In absence or unavailability of antisera particularly for low frequency alleles like Ina, such PCR based method would be extremely helpful to prepare rare donor registry by screening blood donors' at large scale. Red cells of Ina positive donors can be used as in-house reagent red cells for screening and identification of corresponding antibody.

Study on the gene frequency and polymorphism of 11 RBC blood group systems in RhD negtive population in Hunan, China / 中国输血杂志

【Objective】 To investigate the gene frequency and polymorphism of RBC blood group systems in RhD negtive population in Hunan, so as to lay a foundation for clinical blood transfusion and construction of multiple rare blood group database. 【Methods】 Blood samples were taken from 300 RhD negative blood donors, confirmed by serological method, from June 2019 to June 2020,. RHD genotyping was performed by SSP-PCR. For blood donors with typing results as RhD negative plus RHD gene deletion, antigens genotyping of MNS, Duffy, Kell, Domrock, Diego, Kidd, Sciawnna, Colton, Lutheran and Yt RBC blood group systems were performed by SSP-PCR and analyzed by the chi square test of SPSS 20 statistical software. 【Results】 RHD gene deletions accounted for 58.67% (176 / 300) of serological D negative blood donors. The gene frequencies were as follows: MNS: GYPB*S=0.045 5(8/176), GYPB*s=0.954 5(168/176), GYP*Dane=0.039 8(7/176); Duffy: FY*A =0.965 6(170/176), FY*B=0.034 1(6/176); Dombrock: DO*A=0.082 4(14.5/176), DO*B=0.917 6(161.5/176); Diego: DI*A=0.025 6(4.5/176), DI*B =0.974 4(171.5/176); Kidd: JK*A=0.485 8(85.5/176), JK*B=0.514 2(90.5/176); Kell: KP*A=0.005 7(1/176), KP*B=0.994 3(175/176); Lutheran: LU*A=0.005 7(1/176), LU*B=0.994 3(175/176); Yt: YT*A=0.002 8(0.5/176), YT*B=0.997 2(175.5/176). The genotypes of Kell(K+ /k+ ), Scianna and Colton blood groups were KEL*02 /KEL*02, SC*01 /SC*01 and CO*A /CO*B, respectively. The expected frequencies of the combination of type O, RhD negative and other blood group systems were between 1/100 000 to 1/10 000. 【Conclusion】 Among RhD negative blood donors in Hunan, the gene profiles of MNS, Duffy, Domrock, Diego, Kidd, Kell and Lutheran blood group system were polymorphic, and Kell (K+ /k+ ), Colton and Scianna were homozygous. The data of other RBC blood group systems from RhD negative blood donors is of great significance to establish local database of rare blood groups.

Distribution frequency of low-frequency antigen in Kidd, Duffy, MNS, Kell and Diego blood group systems among blood donors, Chongqing area / 中国输血杂志

【Objective】 To investigate the distribution frequency of RBC rare blood group among blood donors in Chongqing, so as to provide basic data for the establishment of regional rare blood group donor database. 【Methods】 A total of 14 805 voluntary blood donors of Chongqing Blood Center from December 2020 to May 2021 were screened for Jk(a-b-) phenotype of Kidd blood group system by urea hemolysis test and confirmed by saline agglutination test. The indirect anti-globulin test was used to screen the Fy(a-) phenotype of Duffy blood group system, s-phenotype of the MNS blood group system and k- phenotype of Kell blood group system in 1 466 O type blood donors. The polyamine test was used to screen the Di(b-) phenotype of Diego blood group system in 856 voluntary blood donors, and confirmed by anti-globulin test. 【Results】 Among the voluntary blood donors in Chongqing, the proportion of Jk(a-b-) phenotype was 0.0203% (3/14 805). The ratio of both Fy(a-b+ ) and S+ s- phenotype among type O blood donors was 0.136 4% (2/1 466), and k- phenotype was not seen. The proportion of Di(a+ b-) phenotype among 856 blood donors was 0.233 6% (2/826). 【Conclusion】 The distribution frequency of rare blood group antigens in the above five blood group systems in Chongqing voluntary blood donors presents regional characteristics.

Application of MALDI-TOF MS in clinical difficult blood group typing / 中国输血杂志

【Objective】 To explore the application of matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) in the genotyping of difficult blood typing samples, and to provide evidence for clinical blood transfusion. 【Methods】 Three ambiguous blood group samples, submitted to Shanghai Blood Center by Shanghai regional hospitals, were studied, of which Sample1 included the proband and his parents. Serological methods were used to perform blood group typing, direct antibody test, unexpected antibody screening and identification test. Blood group genotyping was performed by using the MALDI-TOF MS detection systeme stablished in our laboratory. Sanger sequencing was used to confirm gene mutation sites, and serological or flow methods were used to verify specific samples′ phenotype. 【Results】 Serological results indicated the existence of antibodies against high frequency antigens in sample 1 (including proband and her mother), 2 and 3. The genotyping results of MALDI-TOF MS showed that the proband of sample 1 was Di(a+ b+ ), her father was Di(a-b+ ), her mother was Di(a+ b-), sample 2 was p, and sample 3 was Jr(a-). Sequencing results of three samples were consistent with mass spectrometry typing results. Serological results showed that sample 2 had a p phenotype. The flow cytometry results suggested that sample 3 had a Jr(a-) phenotype. 【Conclusion】 For the first time, we applied MALDI-TOF MS technology to blood type genotyping of ambiguous clinical samples in China. Compared with other genotyping methods such as PCR-SSP, MALDI-TOF MS has the advantages of rapid detection, high throughput and high specificity, which would contribute to identification of difficult blood typing samples in the future, as well as rare blood group screening.

Allelic polymorphism of 13 rare blood group systems in Li Ethnic Group in Hainan / 中国输血杂志

【Objective】 To detect alleles of rare blood group systems of red blood cells (RBC) of Duffy, Diego, Kidd, Dombrock, MNS, Lutheran, Kell, Colton, Scianna, YT, Knops, Indian and Vel of Li Ethnic Group in Hainan, so as to investigate the distribution characteristics of rare blood group alleles and provide references for safe blood transfusion. 【Methods】 The genotypes of 13 rare blood group systems in 300 Li people in Hainan were analyzed by PCR-SSP, and the gene frequency was analyzed . 【Results】 The allele frequencies of Duffy, Diego, Kidd, Dombrock, MNS, and Lutheran blood group systems of 300 Li people were as follows: Duffy: Fya=0.958 3, Fyb=0.041 7; Diego: Dia=0.066 7, Dib=0.933 3; Kidd: Jka=0.450 0, Jkb=0.550 0; Dombrock: Doa=0.101 7, Dob=0.898 3; MNS: M=0.818 3, N=0.181 7, S=0.028 3, s=0.971 7, Mur+ =0.576 7; Lutheran: Aua=0.835 0, Aub=0.165 0. The antigen genes of Kell, Colton, Scianna, Yt, Knops, Indian, Vel blood group systems were not polymorphic, and the genetypes were kk, CoaCoa, Sc1Sc1, YtaYta, KnaKna, InbInb and Vel+, respectively. 【Conclusion】 The allele frequencies of Duffy, Diego, Kidd, Dombrock, MNS and Lutheran blood group systems of Li ethnic group in Hainan were polymorphic, while the allele frequencies of Kell, Scianna, Yt, Knops, Colton, Indian and Vel blood group systems were monomorphic.

Deletion in the A4GALT Gene Associated with Rare "P null" Phenotype: The First Report from India.

BACKGROUND: The present report illustrates a case with rare "P null" phenotype due to a large deletion in chromosome 22q13.2 and with clinically significant anti-PP1Pk antibody. Patient blood management in such cases is challenging. CASE REPORT: The transfusion center supporting the tertiary care referral center in the southern part of India received a blood sample from a trauma case for pre-transfusion testing. An antibody to a high-frequency blood group antigen was initially suspected. Following extensive immune-hematological workup, the patient was diagnosed to have naturally occurring anti-PP1Pk antibody and a rare "P null" phenotype. The genomic DNA of the patient was analyzed by exome sequencing followed by Sanger's sequencing. Molecular diagnostics revealed a large 21-bp deletion in chromosome 22q13.2 which encodes the A4GALT gene, resulting in truncation of seven amino acids I245-251P and resulted in rare "P null" phenotype. Patient blood management strategies were adopted to manage the patient conservatively without blood transfusion. CONCLUSION: A large deletion in chromosome 22q13.2 had resulted in a rare "P null" phenotype in the present case. The patient was a victim of a road traffic accident, required emergency hospitalization, as well as surgical intervention, and his plasma had antibodies to high-frequency antigens. A rare donor registry plays a major role in providing transfusion support to such cases.

Management of patients with rare blood groups in maternity.

We report on our experiences since 2010 with pregnant women with rare blood types. The lack of compatible blood is a challenge for the anaesthetist whose priority is to prevent and treat anaemia in late pregnancy in order to avoid immunisation after transfusion of incompatible blood. In our hospital, the blood type is checked during the first obstetric consult, which is variable, starting from the fourth month of pregnancy. Rare blood types are most often diagnosed in an advanced stage of pregnancy (30 weeks of gestation: WG) due to the late inscription for obstetrics consult, resulting in even later anaesthetic visit. In our 13 patients, the most common blood systems are Duffy, MNS, and RH. 61.5% of the patients have associated antibodies (anti-MNS5). The majority of patients received iron with significant increase of ferritin (17.24 ± 12.95 µg/L versus 262.2 ± 404.4 µg/L, p = .033). Six of the patients had 2-3 injections of EPO between 29 - 36 + 1 WG. There were no transfers for paediatric management of haemolytic disease in the newborn following the birth. Overall, this treatment of patients with a rare blood group has also changed our practices for the follow-up of other pregnant women, and ferritin is more regularly prescribed.Impact statementWhat is already known on this subject? For rare blood groups, the frequency in the general population is less than 1/4000. The most common antibodies at risk of haemolytic disease and 'hydrops fetalis' are anti-D, anti-E, anti-C, and anti-K. The survey of pregnant women with a rare blood type takes into account the maternal risk of 'transfusion deadlock' and haemolytic disease of the newborn.What do the results of this study add? Rare blood types are most often diagnosed in an advanced stage of pregnancy (30 WG) due to the late inscription for obstetrics consults at Maternity. The most common blood systems are Duffy, MNS, RH, and 61.5% of the patients have associated antibodies (anti-MNS5). The most efficient treatment of prenatal anaemia was iron perfusions who allowed significant increase of ferritin and a maternal haemoglobin concentration of 12.1±1.46 g/dL in the ninth month of pregnancy.What are the implications of these findings for clinical practice and/or further research? A pregnant woman with a rare blood group is a situation that requires a technical platform specialised in haemorrhagic risk and a multidisciplinary team, including a blood bank as well as anaesthetic and obstetrical teams, with excellent interdisciplinary coordination.

A case of rare anti-Hro alloantibody in a tertiary care center in India.

Anti-Hro is an alloantibody produced in individuals with -D- phenotype after a sensitizing event. Owing to the rarity of this antigen negative unit, registration in rare donor registries helps in procuring blood components at the earliest. We had a patient of -D- with anti-Hro antibody who required 7 units of red cells which was unavailable at our center. The patients near relatives were typed in search of a similar phenotype blood. Search was made for the rare units and Japanese Red Cross Society, American Red Cross Society, and International Blood Group Reference Laboratory, United Kingdom was contacted. Patient's brother and mother were typed as -D- and one unit from each of them was collected, irradiated, and transfused to the patient. Five units were imported from the Japanese Red Cross Society, Japan. Accessibility for identification and confirmation of rare blood groups and provision of the same can be centralized and liaison with the international registries can go a long way in the provision of blood components at the earliest.