An inherited hemoglobinopathy characterized by impaired synthesis of alpha-globin chains leading to a variable clinical picture depending on the number of affected alleles.

Purpura (from Latin: purpura, meaning \"purple\") is the appearance of red or purple discolorations on the skin that do not blanch on applying pressure. They are caused by bleeding underneath the skin. This term refers to an abnormally increased susceptibility to developing purpura. Purpura are larger than petechiae.