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Quantitative and/or qualitative differences in ABO phenotypes give rise to ABO discrepancies causing difficulties in establishing the accurate phenotype. These discrepant serological reactions result in significant delays in blood bank. The correct typing of the blood group is imperative to prevent ABO incompatibility issues. However, the discrepant results encountered in routine settings are a challenge to immunohematologists. The variants of the ABO occur very rarely particularly true for B subgroups. Here, we present a case study of a healthy blood donor, discrepant results in forward and reverse blood grouping led us to perform adsorption-elution test. The presence of anti-B in the eluate confirmed the presence of weaker variant of B antigen on the surface of red blood cells. Correct identification of blood group is mutually important for donor and recipient to prevent the occurrence of any transfusion reaction. The serologically determined weak B phenotypes, however, require further confirmation through genomic analysis.

Quantitative and/or qualitative differences in ABO phenotypes give rise to ABO discrepancies causing difficulties in establishing the accurate phenotype. These discrepant serological reactions result in significant delays in blood bank. The correct typing of the blood group is imperative to prevent ABO incompatibility issues. However, the discrepant results encountered in routine settings are a challenge to immunohematologists. The variants of the ABO occur very rarely particularly true for B subgroups. Here, we present a case study of a healthy blood donor, discrepant results in forward and reverse blood grouping led us to perform adsorption-elution test. The presence of anti-B in the eluate confirmed the presence of weaker variant of B antigen on the surface of red blood cells. Correct identification of blood group is mutually important for donor and recipient to prevent the occurrence of any transfusion reaction. The serologically determined weak B phenotypes, however, require further confirmation through genomic analysis. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa contaminations in tap water systems have caused severe health problems in both hospital and household settings. To ensure fast and reliable detection, culture-independent methods are recommendable. However, the typically low cell number in water samples requires sample enrichment prior to analysis. Therefore, we developed and optimized an adsorption elution method using monolithic adsorption filtration and subsequent centrifugal ultrafiltration that can be combined with culture-independent detection methods. The principle of adsorption of Pseudomonas aeruginosa by hydrophobic and ionic interactions was studied in modified epoxy-based monoliths. Optimized conditions (5-L initial sample volume at pH 3 filtered for 30 min through hydrolyzed monoliths (MAF-OH) and eluted with beef extract glycine buffer at pH 9.5) achieved a recovery of 67.1 ± 1.2% and a concentration factor of 103. For the first time, we therefore present a culture-independent approach for rapid enrichment and subsequent molecular biological quantification of P. aeruginosa by qPCR from tap water samples by monolithic adsorption filtration. The total enrichment and quantification process takes 4 h. This work further stresses the versatility of the monolithic adsorption filtration and its possibilities as a concentration tool for culture-independent analytics of pathogenic bacteria in the environment. Graphical abstract [ABSTRACT FROM AUTHOR]

Background There is a paucity of data for DEL phenotype in the Indian population. Ours is a tertiary care Regional Blood Transfusion Centre in north India collecting more than 50,000 blood units out of which 8–9% are RhD negative donors. Aim To determine the frequency of DEL phenotype in RhD negative blood donor population at our centre. Material and Methods A total of 200 RhD-negative blood donor samples were included in this study which was conducted over a period of 4 months (October 2013 to January 2014). All these blood samples were tested for extended Rh typing including C, E, c and e antigens and also for adsorption elution testing. The heat elution method at 56 °C in water bath for 10 minutes was utilized. The eluate and the last wash supernatant were used for indirect antiglobulin test against O RhD positive and O RhD negative cells by gel technique using the LISS Coombs' AHG gel cards (Biorad, Morat, Switzerland). Those donor samples which were found positive on adsorption elution testing were also further investigated by gel technique for Direct Antiglobulin test (DAT), Weak D testing and Auto Control test. Results Out of the total 200 Rh D negative donor samples tested, 3 (1.5%) samples were found to give positive result and, thus, were the DEL phenotypes. It was found that 20 (10%) donor samples were positive for C antigen, 5 (2.5%) for E antigen, 200 (100%) for c antigen and 200 (100%) for e antigen. Among the DEL negative (= 197), 193 (98%) were E antigen negative and only 4 (2%) were E antigen positive, whereas among the DEL positive samples (= 3), 2 (66.6%) were E antigen negative and 1 (33.3%) was E antigen positive. The C antigen positivity was only in 2 (66.6%) individuals in the DEL positive group and 178 (90.3%) in the DEL negative samples. All the three samples which were found to be positive as DEL phenotype also gave negative result for DAT, Weak D testing and Auto Control. Conclusion The frequency of DEL phenotype in north Indian RhD negative donor population is 1.5%. [ABSTRACT FROM AUTHOR]