Exposure to toxins or venoms can cause which type of anemia?

Exposure to toxins or venoms can cause which type of anemia?

• A. Aplastic anemia
• B. Iron deficiency anemia
• C. Megaloblastic anemia
• D. Sideroblastic anemia

Answer: (D)

Exposure to toxins like lead disrupts heme synthesis in developing red cells. Lead inhibits enzymes in the heme pathway (ALA dehydratase and ferrochelatase), so iron can’t be incorporated into heme and instead accumulates in the mitochondria of erythroid precursors. This creates ring sideroblasts in the bone marrow and leads to a microcytic, hypochromic anemia. Basophilic stippling can also be seen. The other listed anemias arise from different problems (bone marrow failure, iron deficiency, or impaired DNA synthesis) and do not reflect the toxin-driven block in heme synthesis that defines sideroblastic anemia.

Exposure to toxins like lead disrupts heme synthesis in developing red cells. Lead inhibits enzymes in the heme pathway (ALA dehydratase and ferrochelatase), so iron can’t be incorporated into heme and instead accumulates in the mitochondria of erythroid precursors. This creates ring sideroblasts in the bone marrow and leads to a microcytic, hypochromic anemia. Basophilic stippling can also be seen. The other listed anemias arise from different problems (bone marrow failure, iron deficiency, or impaired DNA synthesis) and do not reflect the toxin-driven block in heme synthesis that defines sideroblastic anemia.