Co-inheritance of β-thalassemia and hereditary spherocytosis in one family

Introduction. The co-inheritance of β-thalassemia and hereditary spherocytosis is a rare clinical phenomenon that complicates diagnosis due to confounding laboratory and clinical presentations. Clinical case. This case report describes a family with β-thalassemia in the mother and hereditary spherocytosis in the father. The daughter inherited β-thalassemia, while the son with moderate anemia, splenomegaly, and hyperbilirubinemia co-inherited a mutation in the HBB gene (β-thalassemia) from the mother and a mutation in the SPTB gene (hereditary spherocytosis) from the father which was confirmed by NGS. The son presented with some characteristics that did not fit the typical diagnostic criteria: paradoxical results of osmotic fragility test alongside the typical features of both diseases (microcytosis, elevated HbA2/HbF, reduced sphericity index). After splenectomy, his hematological parameters improved; however, the presence of mild anemia indicates the persisting influence of thalassemia. Conclusion. This case highlights the necessity of comprehensive genetic testing in patients with atypical course of hemolytic anemia.