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

Dharmesh Chandra Sharma,Sachin Singhal,Sunita Rai,Prakriti Gupta,Shailendra Sharma

doi:10.34172/jrcm.2021.021

Dharmesh Chandra Sharma, Sachin Singhal + Show 3 more

Open Access

https://doi.org/10.34172/jrcm.2021.021

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Abstract

Background: The H antigen is the precursor substance for A and B antigens formation on red blood cells of an individual and absence of it is termed as H deficient phenotype. If H antigen is absent on both RBCs and secretions, and then the resulting blood group is a Classical Bombay phenotype with anti-H antibodies in their serum. If H antigen are absent on RBCs and present in secretions and plasma, the resulting blood group is Para-Bombay phenotype. Genetically Para-Bombay’s lack an active H gene (genotype is hh) but carry at least one Se gene (Secretor gene). Para-Bombay or red blood cell (RBC) H negative secretor individuals may or may not have anti-H in their serum. In both cases routine blood grouping is O. Case Report: Blood sample of 24-year-old female is submitting in blood bank, resulting her routine grouping O RhD positive. Complete blood grouping by Gel technology revels her forward grouping is Oh and reverse grouping B. Patient is secretor for B and H antigens. Absorption and elusion test is negative. Family grouping was also done to find out compatible blood and her family genesis. Conclusion: Patient blood group is Para-Bombay B. Complete blood grouping (Forward and reverse) as well as saliva grouping and absorption /elusion test is advisable when there is a discrepancy in ABH grouping.

Highlights

The classic Bombay phenotype was first reported by Bhende YM et al in 1952 in Bombay, India, and is associated with the ABO and H blood group systems.[1]
If the H antigen is absent on red blood cell (RBC) and present in secretions and plasma, the resulting blood group is the Para-Bombay phenotype
Para-Bombay’s may make a small amount of A or B antigen and H antigen in their plasma, some of which may adsorb to the RBC surface.[4]

Summary

Introduction

The classic Bombay phenotype was first reported by Bhende YM et al in 1952 in Bombay, India, and is associated with the ABO and H blood group systems.[1]. A request for one unit packed Red Blood Cells (RBCs) comes to the blood bank Her blood grouping and RhD typing were done by Gel Technology; Make-Tulip. Sharma et al grouping (cell) was Bombay (Oh) phenotype, and reverse grouping (serum) was B (Anti H is absent in serum), while RhD status was Positive (Figure 1). The patient’s blood group was determined as Para-Bombay B RhD Positive. His blood group was B RhD negative, and transfusion was not required during and after the operation. Both mother and baby were alive and healthy

Discussion

Conclusion