Thalassemia is a heterogenous group of hemoglobinopathies; intermediate thalassemia's phenotype can be very variegated due to different genetic matching. Before NGS-era, diagnosis often mismatched with phenotypes, hiding some genetic findings that nowadays could completely explain clinical presentation. In this report, we emphasize the importance of reevaluating genetic testing to achieve a correct diagnosis in case of phenotype mismatch thalassemia. Starting from a suspect of δ/β thalassemia heterozygosity, reevaluating revealed heterozygosity for α-gene triplication combined to δ and β heterozygosity, a new finding that completely suited patient's clinical manifestation. This case provided the opportunity to underline that an extended study on total globin genes is essential for correct diagnosis of thalassemia, especially when clinical onset phenotypes are more divisive and questionable at a first clinical work-up.
Keywords: genetic retesting; intermediate-thalassemia; α-triplication; β-thalassemia; δ-thalassemia.