Hemoglobin S identification in blood donors: A cross section of prevalence

Introduction

In Brazil, the sickle cell trait (SCT) has an average prevalence of 4% in the general population and 6–10% among Afro-descendants. Although SCT is highly prevalent, a large segment of the population ignores their status. The Therapeutic Guidelines prohibit the transfusion of SCT red blood cells into patients with hemoglobin disorders or severe acidosis and newborns.

Methods

This was a cross-sectional study with data from 37,310 blood donation candidates. The study included only eligible first-time donors qualified to be tested for the presence of hemoglobin S (HbS) at the Fundação Hemominas Juiz de Fora, Brazil. The variables studied were gender, skin color, age, type of donation, place of birth, blood type, result of the solubility test for hemoglobin S (HbST) and hemoglobin electrophoresis (HbEF). Statistical analysis was performed using the Q square test and the Kappa index of agreement for comparing biochemical methods. This project was approved by the National Research Ethics Committee.

Results

The analysis of first-time donor data showed that 7166 were considered eligible. A total of 127 of the 7166 donors were carriers of SCT (1.77%). Among the blood donors, 73.23% were from the local area. The HbST and HbEF were found to be 100% in concordance. Sensitivity was not tested in the present study.

Conclusions

The HbST is highly specific for identifying the HbS, but sensitivity was not tested in this study. The screening of blood donors for abnormal hemoglobins is useful, helping to detect and counsel heterozygous people. The study seeks to identify the prevalence of SCT in a region of Brazil.

Ethics and Collateral Findings in Pragmatic Clinical Trials

Pragmatic clinical trials (PCTs) offer important benefits, such as generating evidence that is suited to inform real-world health care decisions and increasing research efficiency. However, PCTs also present ethical challenges. One such challenge involves the management of information that emerges in a PCT that is unrelated to the primary research question(s), yet may have implications for the individual patients, clinicians, or health care systems from whom or within which research data were collected. We term these findings as ?pragmatic clinical trial collateral findings,? or ?PCT-CFs?. In this article, we explore the ethical considerations associated with the identification, assessment, and management of PCT-CFs, and how these considerations may vary based upon the attributes of a specific PCT. Our purpose is to map the terrain of PCT-CFs to serve as a foundation for future scholarship as well as policy-making and to facilitate careful deliberation about actual cases as they occur in practice.