The thalassemias are categorized into two broad disease groups: alpha-thalassemia and beta-thalassemia. Alpha-thalassemia is characterized by a decrease in or defective production of alpha-globin chains. There are four major types of alpha-thalassemia, and each depends on the number of alpha-globin alleles that are lost. These include the silent carrier state, alpha-thalassemia trait, HbH disease, and hydrops fetalis (Hb Barts). Beta-thalassemia is characterized by a decrease in or defective production of beta-globin chains. There are three major types of beta-thalassemia, and each depends on the degree of production of beta-globin chains. These include beta-thalassemia minor, beta-thalassemia intermedia, and beta-thalassemia major (Cooley's anemia). The beta-thalassemias can also be categorized by the degree of beta-globin chain production (B0 or B+ phenotypes).
Thalassemia classification
Thalassemia physical examination
Glucose-6-phosphate dehydrogenase deficiency classification
Glucose-6-phosphate dehydrogenase deficiency physical examination
Thalassemia laboratory findings
Hemolytic anemia classification
Methemoglobinemia laboratory findings
Fanconi anemia laboratory findings