[Contribution to the establishment of reference ranges for total immunoglobulin E: a cross-sectional study among blood donors in Abidjan (Ivory Coast)].

Introduction: the total immunoglobulins E (IgE) is used as a biomarker in the diagnosis of allergic diseases. Its interpretation is generally based on reference values established in Western populations, without considering the epigenetic and environmental specificities of tropical countries. In sub-Saharan Africa, factors such as living conditions, polyparasitism, and the diversity of allergenic exposures can strongly influence the IgE levels. The main objective of this study is to establish reference ranges for the total IgE in blood donors in Abidjan as healthy controls in our context. Methods: we conducted an analytical cross-sectional study from September to November 2023 at the National Blood Transfusion Centre in Abidjan. A random sample of 136 voluntary, asymptomatic blood donors aged 18 to 60 years was included after obtaining informed consent. Each participant underwent a complete blood count, total IgE measurement using the ELFA method on the VIDAS® automated platform, and a parasitological examination of stool samples. Statistical analyses were performed using SPSS version 22.0, with Student's t-test and ANOVA applied for comparing means, and Pearson's correlation test used to assess relationships between quantitative variables. Results: the mean age of participants was 34.5±11.8 years. Men represented 94.9% of the sample. The mean IgE level was 347.1±598.6 KU/L, with 41.2% of donors having a level >150 KU/L. A significant negative correlation was observed between IgE levels and age (r = -0.37; p = 0.03), as well as a positive correlation between IgE levels and eosinophil count (r = 0.41; p = 0.014). Conclusion: this study shows average levels of total IgE higher than international standards, probably related to regional specificities. These results support the establishment of local standards to adapt the interpretation to Ivorian realities.