Clinical Features

Minor variant: unremarkable symptoms (low risk of hemolysis, rarely splenomegaly)

Major variant

• Severe hemolytic anemia that often requires transfusions → secondary iron overload due to hemolysis, transfusion, or both → secondary hemochromatosis

• Hepatosplenomegaly

• Growth retardation

• Skeletal deformities (high forehead, prominent zygomatic bones, and maxilla)

• Transient aplastic crisis (secondary to infection with parvovirus B19) [7]

Sickle cell beta thalassemia

• Features of sickle cell disease

• Severity depends on the amount of β-globin synthesis.

Silent carrier: asymptomatic

Alpha thalassemia trait: mild hemolytic anemia with normal RBC and RDW

Hemoglobin H disease

• Jaundice and anemia at birth

• Chronic hemolytic anemia that may require transfusions → secondary iron overload due to hemolysis, transfusion, or both → secondary hemochromatosis

• Hepatosplenomegaly

• Skeletal deformities (less common)

• Compared to thalassemia beta, symptoms in adults are generally less severe.

Hb-Bart's hydrops fetalis syndrome (most severe variant of alpha thalassemia)

• Intrauterine ascites and hydrops fetalis, severe hepatosplenomegaly, and often cardiac and skeletal anomalies

• Incompatible with life (death in utero or shortly after birth)