There are 4 clinical types of alpha thalassemia that result from the loss of genes encoding the alpha chain:
Alpha thalassemia minima (silent alpha thalassemia carrier, -α/αα): changes in the general analysis of blood may not be observed.
Alpha thalassemia minor (severe thalassemia carrier,-- /αα or ,-α/-α): moderate anemia, hypochromia, and microcytosis are determined in these patients.
HbH disease (alpha thalassemia disease,--/-α): moderate hypochromic hemolytic anemia, splenomegaly, anemic crises due to viral infections and some drugs are observed. These patients may also have heart problems, gallstones, lower limb ulcers and folic acid deficiency.
Hb Bart hiropd fetalis (homozygous alpha⁰-thalassemia,--/--): this hemoglobinopathy, observed with severe hemolytic anemia, is detected while the fetus is still in the womb.
Synthesis of alpha-globin chains does not occur in these patients. Clinically, hydrops and ascites are determined in patients.
