An acquired form of alpha-thalassemia characterized by a myelodysplastic syndrome (MDS) or more rarely a myeloproliferative disease (MPD) associated with hemoglobin H disease (HbH).

An ecchymosis (bruise) refers to the skin discoloration caused by the escape of blood into the tissues from ruptured blood vessels. This term refers to an abnormally increased susceptibility to bruising. The corresponding phenotypic abnormality is generally elicited on medical history as a report of frequent ecchymoses or bruising without adequate trauma.