thrombopenia vs blood disease

thrombopenia and blood disease both are nouns.

Word	Noun	Adjective	Verb	Adverb
thrombopenia	Yes	No	No	No
blood disease	Yes	No	No	No

As nouns, blood disease is a hypernym of thrombopenia; that is, blood disease is a word with a broader meaning than thrombopenia:

thrombopenia: a blood disease characterized by an abnormally small number of platelets in the blood
blood disease: a disease or disorder of the blood

Other hypernyms of thrombopenia include blood disorder.

thrombopenia (noun)	blood disease (noun)
a blood disease characterized by an abnormally small number of platelets in the blood	a disease or disorder of the blood