Laboratory Characterization of Elevated Fetal Hemoglobin in Children with Normal CBC Parameters in Sulaymaniyah City/ Iraq
DOI:
https://doi.org/10.24237/04.04.771Keywords:
Fetal hemoglobin, β-thalassemia, Hemoglobinopathy, Hereditary Persistence of Fetal Hemoglobin (HPFH).Abstract
Fetal hemoglobin (HbF) is the predominant hemoglobin during fetal development, typically replaced by adult hemoglobin after birth. However, in some individuals, HbF continues to be produced at low levels into adulthood a benign genetic disorder known as Hereditary Persistence of Fetal Hemoglobin (HPFH). The aims to investigate cases of elevated HbF in individuals with otherwise normal complete blood count (CBC) parameters, by comparing hematological indices and hemoglobin fractions. This cross-sectional study, investigated hematological and biochemical characteristics in 50 children aged 1–10 years. Demographic data such as age and gender were recorded. Hematological parameters were measured using the NANA-5 Geno TEK analyzer, and hemoglobin fractions were assessed with the Bio-Rad D-10 High-Performance Liquid Chromatography (HPLC) system. Statistical analysis was conducted using SPSS version 25, applying Kruskal–Wallis, Mann-Whitney U, and Chi-square tests, with p-values (<0.05) considered significant in term of statistic. The sample patient group showed intermediate hematological indices between β-thalassemia and normal controls, with elevated HbF (median 4.1%) but lower than thalassemia cases (median 9.85%). HbA₂ was significantly elevated in β-thalassemia. HbF levels were significantly associated with age and gender.
This study identifies a benign subgroup with elevated HbF and normal blood indices, likely due to HPFH or regulatory polymorphisms. Distinct from β-thalassemia minor, these individuals show no hematological abnormalities. Age- and sex-based variations support a genetic basis, highlighting the importance of integrated diagnostics to avoid misclassification.
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