Etiology, Investigations, and Differential Diagnosis of Microcytic Hypochromic Anemia

Introduction

Microcytic hypochromic anemia is a condition characterized by red blood cells that are smaller than normal and have reduced hemoglobin content. This type of anemia often results from iron deficiency, chronic diseases, and genetic disorders affecting hemoglobin synthesis.

Etiology

Iron Deficiency Anemia (IDA)

• Most common cause
• Caused by inadequate dietary intake, blood loss, or malabsorption

Thalassemia

• Genetic disorder affecting hemoglobin production
• Leads to ineffective erythropoiesis and hemolysis

Anemia of Chronic Disease (ACD)

• Associated with chronic inflammatory or infectious diseases
• Involves iron sequestration in macrophages and impaired erythropoiesis

Investigations

Laboratory Tests

• Complete Blood Count (CBC): Shows low Mean Corpuscular Volume (MCV) and low Mean Corpuscular Hemoglobin (MCH)
• Serum Iron, Total Iron Binding Capacity (TIBC), and Ferritin: Differentiates between IDA and ACD
• Hemoglobin Electrophoresis: Used for diagnosing thalassemia

Peripheral Blood Smear

Examining red blood cell morphology can help in the differentiation of microcytic anemia subtypes.

Differential Diagnosis

Distinguishing Between Causes

Condition	Key Features
Iron Deficiency Anemia	Low ferritin, high TIBC, normal-to-low serum iron
Thalassemia	Target cells on peripheral smear, normal iron levels
Anemia of Chronic Disease	High ferritin, low TIBC, normal-to-low serum iron

Conclusion

Microcytic hypochromic anemia requires a thorough evaluation of etiology through laboratory investigations. Differentiating among iron deficiency anemia, thalassemia, and anemia of chronic disease is essential for targeted treatment.