Challenges in diagnosis of thalassemia syndromes

Abstract

Hemoglobinopathies are a group of autosomal recessive disorders characterized by either a reduced synthesis of one or more normal globin chains or the synthesis of a structurally abnormal globin chain or, in a few cases, by both that is, the reduced synthesis of a haemoglobin (Hb) variant. Depending on the mutations, these patients may exhibit distorted Hb patterns along with altered red cell indices, both of which can be used to support identification by diagnostic tools. The approach in the diagnosis of hemoglobinopathies and thalassemia depends upon the target geographical population and aim of testing. Red cell indices, Hb pattern analysis on high-performance liquid chromatography, and Hb capillary-zone electrophoresis are the first-line screening tests, and molecular testing helps confirm the diagnosis and is also useful in prenatal and preimplantation genetic diagnosis. Thalassemia patients need lifelong medical care, receiving trasfusions and supplemental therapies, and therefore, timely diagnosis and screening is essential. In the present paper, we review the potential pitfalls and interfering factors in their diagnosis.

Keywords: HbA2; Hemoglobin; Population screening; Prenatal diagnosis; Thalassemia.