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Published on: September 18, 2016
Frequency of subgroups of the antigen “a” among volunteer donors
Katherine Parra-Jaramillo1, Rosa F Chiriboga-Ponce1,2
1Facultad de Medicina-Carrera de Bioquímica Clínica. Pontificia Universidad Católica del Ecuador, Quito, Ecuador.
Introduction:
The presence of weak variants of blood type A represents a challenge in the practice of immunohematology for discrepancies in the time of the classification. It is common in blood banks to perform a forward and reverse typing for the purpose of confirming the blood type, but not all the people with a subgroup A2 have developed anti-A1 antibodies.
Objective:
We present a descriptive, observational and transversal study that establishes the proportion of subgroups of A antigen with the analysis of manual tube technique and monoclonal antibodies like anti-A, anti-A1 (Dolichus biflorus lectins extract) and anti-H.
Methods:
The analysis involved a total of 818 samples of voluntary blood donor, selected by random sampling, which were initially classified as 737 of Type A, and 81 as Type AB, with a confidence level of 95% (alpha error of 5% and 3% of precision).
Results:
The present study evaluated the existence of the subgroups A1, A2, A1B, A2B, A intermediate and A intB.
Conclusions:
It is recommended the identification of subgroups in different types of blood in the laboratory and blood banks.
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