Etiology, Investigations, and Differential Diagnosis of Microcytic Hypochromic Anemia

Iron Deficiency Anemia: Pathogenesis, Clinical Features, and Laboratory Findings

Introduction

Microcytic hypochromic anemia is a common hematologic disorder characterized by small, pale red blood cells. Iron deficiency anemia is the most prevalent cause, resulting from inadequate iron intake, impaired absorption, increased demand, or chronic blood loss.

Etiology

• Dietary Deficiency: Insufficient iron intake from food sources.
• Malabsorption: Conditions such as celiac disease or gastric bypass can hinder iron absorption.
• Increased Demand: Pregnancy and infancy require higher iron levels.
• Chronic Blood Loss: Menstrual bleeding, gastrointestinal bleeding from ulcers or malignancies.

Clinical Features

• Pallor
• Fatigue and weakness
• Shortness of breath
• Brittle nails and hair loss
• Pica (craving for non-nutritive substances like ice or clay)

Investigations

• Complete Blood Count (CBC): Low hemoglobin, microcytosis, hypochromia.
• Serum Ferritin: Decreased in iron deficiency anemia.
• Total Iron Binding Capacity (TIBC): Elevated.
• Peripheral Blood Smear: Shows microcytic, hypochromic red cells.
• Bone Marrow Examination: Reserved for atypical cases.

Differential Diagnosis

• Thalassemia: Genetic disorders causing defective hemoglobin production.
• Sideroblastic Anemia: Impaired hemoglobin synthesis leads to abnormal iron accumulation.
• Chronic Disease Anemia: Inflammatory diseases affecting iron metabolism.
• Lead Poisoning: Causes microcytic anemia due to disrupted enzyme function.

Treatment

Iron deficiency anemia is managed with oral iron supplementation, dietary modifications, and treatment of underlying causes. Parenteral iron therapy may be required for refractory cases or severe deficiency.

Conclusion

Microcytic hypochromic anemia requires thorough evaluation to determine the underlying cause. Iron deficiency anemia is highly treatable with appropriate intervention, improving patients' overall health and quality of life.