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.

Molecular characterization of rare D--/D-- variants in individuals of Indian origin.

BACKGROUND: Rh antigens are critical in haemolytic disease of the foetus and newborn (HDFN). The D-- phenotype is a rare blood group characterised by the lack of expression of C, c, E and e antigens at the surface of red blood cells because of mutations in both RHCE alleles inactivating the expression of a "normal" protein. The aim of the study was to determine the molecular basis of D-- individuals of Indian origin. MATERIALS AND METHODS: Ten Rh D-positive postnatal women who had produced antibodies against all Rh antigens, except D, leading to HDFN and foetal loss, were investigated. Extensive serological and molecular (polymerase chain reaction [PCR] using sequence-specific primers), quantitative multiplex PCR of short fluorescent fragments (QMPSF), and Sanger sequencing analyses were carried out. RESULTS: Serological testing with anti-C, anti-c, anti-E, and anti-e reagents showed absence of the four antigens in all ten index cases, as well as in three siblings. Flow cytometry indicated absence of these antigens with a typical exalted expression of the D antigen, thus confirming the rare D-- phenotype. Molecular analysis by QMPSF suggested homozygous CE-D hybrid alleles causing the D-- phenotype: RHCE-D(3-9)-CE (n = 11), RHCE-D(3-8)-CE (n=1), and RHCE-D(2-6)-CE (n=1). DISCUSSION: For the first time, we report the molecular basis of the D-- phenotype in the Indian population. Identification and characterisation of RHCE-null variants by molecular methods can help resolve transfusion-related problems in these individuals. Family studies of index cases helped to identify rare blood donors and offer counselling to females of child-bearing age on the complications involved in such pregnancies.