Etiology, Investigations, and Differential Diagnosis of Microcytic Hypochromic Anemia

Etiology of Microcytic Hypochromic Anemia

Microcytic hypochromic anemia is a condition characterized by small, pale red blood cells that arise due to impaired hemoglobin synthesis.

Common Causes

• Iron Deficiency Anemia: The most common cause, due to inadequate dietary intake, chronic blood loss, or malabsorption.
• Thalassemia: A genetic disorder affecting hemoglobin production.
• Sideroblastic Anemia: A rare disorder caused by defective heme synthesis.
• Anemia of Chronic Disease: Chronic infections, autoimmune disorders, and malignancies can impair iron utilization.
• Lead Poisoning: Inhibition of heme synthesis due to toxic effects of lead.

Investigations

Diagnosis is based on laboratory investigations:

• Complete Blood Count (CBC): Shows low mean corpuscular volume (MCV) and reduced mean corpuscular hemoglobin (MCH).
• Serum Iron Studies: Assess iron levels, total iron-binding capacity (TIBC), and ferritin.
• Hemoglobin Electrophoresis: Helps detect hemoglobinopathies like thalassemia.
• Bone Marrow Examination: Evaluates iron stores and erythropoiesis in refractory cases.

Differential Diagnosis

Microcytic hypochromic anemia must be differentiated from other forms:

• Normocytic normochromic anemia (associated with chronic disease and renal failure).
• Macrocytic anemia (due to vitamin B12 or folate deficiency).