A rare report of H-partially deficient, non-secretor phenotype from India. An Ah like the rèunion and unlike a Para Bombay-Clarifying misinterpretations.

BACKGROUND: H-deficient phenotypes are classified as H-deficient non- secretors (Bombay Oh), H-deficient secretors (Para Bombay), and H-partially deficient non-secretors (O h reunion, Ah and Bh, ABh). REPORT: We report the first case of H-partially deficient non-secretor- the Ah phenotype from India. What makes this report interesting is that they do not fit into the Bombay, or the Para Bombay series of H-deficient phenotypes and these partially deficient non-secretors were exclusively found on Réunion Island, off the East Coast of Africa in 1982. These reunion type phenotypes have not been reported since then and may lead to misinterpretations and confusions when encountered in the current existing laboratory settings especially in the low income (LIC's) and low middle income (LMIC's) countries like our own. Moreover, literature from LMIC and LIC incorrectly uses Ah/Bh for parabombay phenotypes. CONCLUSIONS: H-deficient phenotypes are rare, challenging to identify and assign correct notations. Hence, we have highlighted characteristic differences between H-deficient phenotypes and illustrated a diagnostic laboratory approach to correctly identify and assign notations to them especially in the resource constrained settings.

Molecular red cell genotyping of rare blood donors in South Africa to enhance rare donor-patient blood matching.

BACKGROUND: Molecular red cell genotyping is devoid of serology limitations such as the scarcity of rare antisera and the possibility of inconclusive results due to biological interferences. Blood incompatibility can result in immune transfusion reactions such as haemolytic transfusion reactions or haemolytic disease of the foetus and newborn. OBJECTIVE: The study aimed to use molecular red cell genotyping to identify rare blood group donors among South African blood donors. METHODS: Red cell genotyping data were extracted retrospectively from the BIDS XT genotyping software in the Immunohaematology Reference Laboratory from January 2015 to August 2016. The ID CORE XT genotyping assay was used to identify the single nucleotide polymorphisms of 10 blood groups system alleles in 150 donors. Associations between the resultant genotypes and predicted phenotypes, ABO group, RhD type, race group and gender were studied. RESULTS: Significant red cell genetic variability was noted among the numerous South African donor genotypes identified in this study. Genotyping further confirmed the presence of at least one of the 16 rare genotypes in 50 donors. Group O Black donors were associated with two rare blood types, while several other rare blood types were found only in White donors, supporting an association between ABO/Rh subtype, race group and rare blood types. CONCLUSION: Targeted screening of donors for antigen-negative rare blood units for patients should be done to reduce the risk of haemolytic transfusion reactions and haemolytic disease of the foetus and newborn.

Blood Group Distribution in Switzerland - a Historical Comparison.

BACKGROUND: Ethnicities differ in prevalence of blood groups and antigens. Substantial donor-recipient mismatch within mixed-ethnic societies may render certain recipients at higher risk for alloimmunization. Data regarding antigen distribution within Switzerland by ethnicity is limited. We examined immigration patterns against the distribution of ABO blood groups using large cross-sectional Swiss samples spanning 70 years. METHODS: Historical ABO blood group distribution data (1940-1945) from Swiss army personnel (n = 275,664) were sourced from the literature. Recent blood group phenotypes of 122,925 individuals who presented themselves at army recruitment centers (2004-2015) were obtained, alongside a validation sample of 175,202 patients from a university hospital. Two-sample tests with z-statistics assessing blood groups between samples were used. RESULTS: The respective proportions of A (47.2% and 45.2%), B (8.4% and 9.8%), and AB (3.0 and 4.1) in the historical and recent army samples were significantly different (p < 0.001), while group O was not. Conclusion: ABO blood groups in Switzerland have remained stable despite substantial immigration with a changing foreign-national profile. Further research is needed to improve the understanding of antigen differences in newly introduced ethnic groups. Blood product requirements and public health initiatives aimed at recruiting blood donors would benefit from this information.