Aplastic anemia

A rare disorder that results in underproduction of bone marrow hematopoietic cells. Hence patients usually present with pancytopenia and their bone marrow appears markedly hypocellular (usually <10% cellularity). Aplastic anemia can be secondary to multiple causes including but not limited to drugs, infections (e.g. viruses such as EBV and parvovirus), neoplastic disorders (e.g. myelodysplastic syndrome or paroxysmal nocturnal hemoglobinuria), and autoimmune disorders.