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تسجيل

Nosology of Hemoglobinopathies

المؤلف:  Hoffman, R., Benz, E. J., Silberstein, L. E., Heslop, H., Weitz, J., & Salama, M. E.

المصدر:  Hematology : Basic Principles and Practice

الجزء والصفحة:  8th E , P461

2026-02-26

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Inherited abnormalities of the Hb molecules that cause morbidity are called hemoglobinopathies and thalassemias. Many of these conditions produce diseases (e.g., sickle cell anemia, thalassemia, unstable Hbs, Hbs with altered oxygen affinity, M Hbs) that are especially important to hematologists. A few acquired conditions lead to modifications of Hb (e.g., carbon monoxide exposure, producing carboxy hemoglobinemia, nitrite exposure causing methemoglobinemia) that produce clinical abnormalities. These situations are summarized by the term acquired hemoglobinopathies or dyshemoglobinemias.

Most of the more than 1200 mutations of the globin gene that have been described produce no disease or only trivial clinical effects. The remainder can be classified according to the hematologic and clinical phenotypes that cause reduced solubility with hemolytic anemia (unstable Hbs and polymerizing Hbs, such as sickle Hb); Hbs with altered oxygen affinity; Hbs predisposing to methemoglobin formation; and the thalassemias involving abnormal synthesis of one or more globin chains with anemia, hemolysis, and alterations of erythropoiesis. Some mutations, such as that responsible for HbE, can alter the structure and synthesis of the molecule. A classification of hemoglobinopathies and thalassemias is provided in Table 1. Individual conditions are discussed in the chapters already cross-referenced in earlier sections of this chapter.

Table1. Classification of Hemoglobinopathies and Thalassemias