Homozygous delta-beta Thalassemia in a Child: a Rare Cause of Elevated Fetal Hemoglobin.

BACKGROUND: Delta beta (δβ) thalassemia is an unusual variant of thalassemia with elevated level of fetal hemoglobin (HbF). Homozygous patients of this disorder, unlike β-thalassemia, show mild anemia. Only few cases of δβ-thalassemia have been reported from India in the available indexed English literature. CASE PRESENTATION: A four-year old male child was evaluated for recent-onset jaundice. Hematological investigations showed mild anemia with microcytic hypochromic red cells. A comprehensive analysis of hemoglobin by high-performance liquid chromatography (HPLC) showed complete absence of HbA and HbA2 with HbF constituting 100% of the hemoglobin. Hemoglobin analysis of both parents showed elevated level of HbF with normal HbA2. A final diagnosis of δβ-thalassemia in the child with both parents being carriers was rendered. CONCLUSION: Delta beta-thalassemia is an uncommon cause of markedly elevated fetal hemoglobin beyond fetal period. Clinical and haematological parameters should be evaluated to render an accurate diagnosis.