Microcytic Anemia

Epidemiology and Etiology:

• Causes:
• Iron deficiency
• Thalassemia
• Lead poisoning

Common sites:

Gross features:

Histologic features:

• microcyte with central pallor
• <6um (normal 7um)
• central palor > 1/3 of diameter of cell
• may see ghost cells

Immunophenotype:

Marker:

Sensitivity:

Specificity:

Molecular features:

Other features:

• Useful indices:
• MCV / Erc:
• If < 13.3 – suggestive of thalassemia trait
• If > 13.3 – suggestive of iron deficiency
• RDW / Erc:
• If < 3.3 – suggestive of thalassemia trait
• If > 3.3 – suggestive of iron deficiency
• If significant microcytosis (MCV < 65) without anemia, this is strongly suggestive of thalassemia trait or other related haemoglobinopathy
• Hgb is normal range, or Erc is higher than normal

References:

• CAP Color Atlas of Hematology, 1998