Para-Bombay phenotype: A case report from a tertiary care hospital from South Gujarat

Abstract

The blood specimen of a 30-year-old male donor showing a discrepancy in cell and serum grouping was targeted for detailed study at the blood bank at tertiary care hospital in South Gujarat. Forward grouping showed group as “O” RhD positive and reverse grouping as group “A.” Further testing confirmed that the individual's blood group was para-Bombay A (para-AH). Family members were screened, and younger brother was also identified as para-Bombay phenotype. The para-Bombay phenotype is very rare, and only a few cases have been reported from India. This blood group is characterized by the absence of ABH antigens on red blood cells (RBC's) with the presence of ABH substances in body secretions or by the weak expression of ABH antigens on RBC's with the absence or presence of substances in body secretions. This rare phenotype can be mislabeled as “O” if all detailed investigations are not performed.

Evaluation, Exploration and Management Strategies of a First Reported Rarest Case of Para-Bombay Blood Phenotype with E-Beta Thalassaemia from Bangladesh

“…Spectrum of the H blood-group-deficient phenotypes showed mutation of FUT 1 (H gene) while, deletion of FUT2 (Secretory gene) found in diverse ethnic groups with Bombay Phenotype ; on the other hand, active FUT2 found among Para-Bombay . 3,4,9,11 Among the Bombay phenotype in India, a high level of consanguinity has been seen. 1,4 On the other hand, it is quite rare, 1 in 250,000 among Caucasians with 1: 10 6 prevalence in Europe, 4,9,12 while, H-deficient population in Iran is 0.0008%.…”

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

“…This is due to the absence of the A and B antigens, which mimic the O phenotype; however, it is incredibly important to consider the presence of the H antigen in all of the ABO blood types. Thus, transfusion of A, B, or O blood types into patients with the Bombay blood group can result in a classic manifestation of acute hemolytic reactions due to the production of anti-H antigen antibodies [ 3 ]. Therefore, patients of the Bombay blood group may only receive transfusions of blood or blood components from donors of the same blood phenotype.…”

“…The Bombay phenotype arises from a point mutation in the H gene, resulting in the improper production of the functional protein needed for H antigen synthesis, called fructosyltransferase [ 1 , 3 ]. Contrastingly, in patients with the Bombay blood group, there is an intrinsic inability to produce the H antigen due to the protein deficiency.…”

“…The clinical significance of the Bombay blood group includes the inability to transfuse with other blood groups, such as A, B, AB, and especially the O type [ 2 ]. This can lead to fatal hemolytic transfusion reactions, with a classic triad of symptoms including fever, flank pain, and red-brown urine, along with the development of extravascular hemolysis [ 3 ]. Differentiating the O blood group from the Bombay blood group in a blood bank depends initially on reverse grouping.…”

Para-Bombay B phenotype: a rare ABH blood group variant at tertiary care hospital, Gwalior India

“…FUT2 recognizes type 1 chain precursors to form H type I antigens in secretions and tissues such as secretary glands and digestive mucosa. 14 Bombay phenotype is characterized by the lack of ABH blood group antigens on the surface of RBCs and in saliva, resulting in the inheritance of FUT1 (h/h) and FUT2 (se/ se) genes. 12 All the Bombay phenotype cases reported in India showed only the T725G mutation of FUT1 and the 10 kb gene deletion of FUT2, which are responsible for this rare phenotype, suggesting its unicentric origin.…”