Both Myelodysplastic Syndrome (MDS) and Aplastic Anemia (AA) can present with pancytopenia (low blood counts). However, their bone marrow appearances are fundamentally different. In Aplastic Anemia, the bone marrow is hypocellular or even acellular, meaning it is largely replaced by fat, with a severe reduction in blood-forming cells (hematopoietic cells). In contrast, in MDS, the bone marrow is usually normocellular or hypercellular—it is packed with blood-forming cells. The problem in MDS is not a lack of cells, but that these cells are dysplastic (abnormally developed) and undergo increased apoptosis (programmed cell death), leading to ineffective blood production despite a full-looking marrow. Finding a hypercellular marrow in a pancytopenic patient strongly points away from AA and towards MDS or other infiltrative processes.

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Zambia

• Joseph Soko – 101 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies