English

Abstract

INTRODUCTION: The blood group serology plays an important role in transfusion medicine. The discovery of a rare blood group, Bombay (Oh) Phenotype by Bhende et al in 1952 in Mumbai formerly (Bombay) was important in the field of immunohematology. The discovery later helped Watkins and Morgan1 (1959) and Gerard et al2 (1982) to elucidate biosynthetic pathway for ABH and Lewis (Le) antigens suggesting the secretor (Se) and (H) are closely linked structural genes. Recently, molecular genetic studies were carried out to determine the role of the H, Se and Le genes in the expression of H antigen in secretions and Lewis blood group antigen on erythrocytes. 3,4. It is known that the precursor protein from which all blood groups are formed is termed as the “H” Antigen. This ‘H’ antigen either translates into ‘A’ antigen (blood group A) or into ‘B’ Antigen (blood group B) or into both A and B Antigens (blood group AB) or it remains as ‘H’(blood group ’O’).In the case of Bombay blood group, there is absence of ‘H’ Antigen itself. Therefore ‘A’, ‘B’, ‘AB’ and ‘O’ which are all different manifestations of ‘H’ are alien to persons with Bombay blood group. The Bombay blood group is termed ‘Oh’ meaning absence of ‘H’ Antigen. CASE REPORT: A 25 year old Post C.S. 2nd gravidae, at term pregnancy was referred from Purulia District Hospital and admitted in our hospital through emergency. The patient gave history of irregular antenatal checkup and did not consume iron folate tablets. Her menstrual history was normal. Her previous pregnancy and caesarean section were uneventful with no previous history of blood transfusion. There was no family history of Thalassemia or blood transfusion. On examination the patient was severely anaemic (Hb-4.5 gm %) with tachycardia and pedal oedema of lower limbs. Her blood pressure was 110/68 mm Hg Obstetric examination revealed full term post caesarean pregnancy with longitudinal lie, cephalic presentation, F.H.S.-146/min, regular with mild uterine contraction. Per vaginal examination suggested that she was in early labour. Immediate decision for blood transfusion and termination of pregnancy by LUCS was taken. The blood was sent for grouping and cross matching to our Blood Bank where she was diagnosed to have the Bombay Blood group after reverse grouping. As this group is very rare, we could not find a single unit of this group in Bankura district and immediate blood transfusion could not be performed. Ultimately, after 4hours of admission, LUCS was performed without blood. After emergency caesarean section the first 72 hours were uneventful. On the 4 th post-operative day, the