Why there is no spleenomagaly

Why there is no spleenomagaly …no extra medullary haematpoiesis in Aplastic anemia ?? While its bone marrow failure syndrome so shouldn’t other organs compensate for hematopoieis?

Hematopoetic stem cells in bone marrow migrates to the spleen and Liver as a response to hematopoietic stress. HSCs from bone marrow is responsible for extramedullary hematopoesis. In aplastic anemia these stem cells in Bone marrow are affected thus no migration= no extramedullary hematopoesis.