Detection of hemoglobin variants in patients tested for Hemoglobin A1c

Abstract

Background: The genetics in hemoglobin variants in Costa Rica are a result of the crossing of autochthonous indigenous characters with European, African and other immigrant populations. All of these contributed to the genetic mixture that is currently present in Costa Rica's population. The most distributed hemoglobinopathies in the human population are: hemoglobin S, C, D, and E, with hemoglobin S being the most frequent and having the most serious consequences.
Objective: detection of hemoglobin variants in patients who were examined for hemoglobin A1c in the Clinical Chemistry section of the Filadelfia Clinic Laboratory, from January to October 2018. The clinic is in Canton of Carrillo, Guanacaste (Costa Rica), and it is part of the social security system.
Methods: 2775 blood samples and their respective data were analyzed from patients of the nine basic health teams that make up the Carrillo Health Area and required a study for glycosylated hemoglobin from January to October 2018. The analysis was performed in the Carrillo Health Area Laboratory. The samples were collected in vacutainer tubes containing EDTA and analyzed in the TOSOH HLC-723GX automated equipment, using the HPLC cation exchange chromatography methodology with the separation and quantification of the different hemoglobin fractions. The data was then analyzed in a Microsoft Excel template.
Results: in the 2775 patients examined for hemoglobin A1c, 167 (6.0%) were found to be carriers of hemoglobin variants, with a frequency of 1/17, where 97% corresponded to heterozygotes for hemoglobin S, 3% heterozygous for hemoglobin C, and none for variant D. The presence of variants was observed in the 9 basic teams of integral health care of the area, and the distribution varied from 4% to 9,3% between them.
Conclusions: A total of 6% of the samples analyzed showed a hemoglobin variant, being hemoglobin S the most predominant. This characteristic present in the population of Canton of Carrillo deserves attention at the public health level. The existing methodology at the level area allows professionals to study a population group at risk that deserves surveillance and genetic counseling, in order to raise awareness about the problem, reduce the incidence of the disease, and prolong the survival of those affected by it.