Overview
Definition
A microcytic, hypochromic anemia caused by inadequate iron stores needed for hemoglobin synthesis.
Epidemiology
The most common nutritional deficiency and the most common cause of anemia worldwide.
Etiology & Risk Factors
- Blood loss (GI bleeding from ulcers/colon cancer, or heavy menstruation)
- Inadequate dietary intake (common in infants or vegans)
- Malabsorption (Celiac disease, gastric bypass surgery)
- Increased demand (pregnancy)
Clinical Symptoms
- Fatigue, weakness, pallor
- Pica (craving non-nutritive substances like ice, dirt, or clay)
- Koilonychia (spooning of the nails)
- Glossitis (smooth, swollen tongue)
- Restless leg syndrome
Clinical Approach
Diagnosis
- CBC: Low Hemoglobin, Low MCV (< 80 fL - microcytic), Low MCH (hypochromic), High RDW
- Iron Studies (Diagnostic): Low Ferritin (most sensitive/specific marker for total body iron stores), Low Serum Iron, High TIBC (Total Iron Binding Capacity), Low Transferrin Saturation
- Peripheral Smear: Microcytic, hypochromic RBCs, 'pencil cells'
Management
- Oral Iron supplementation (Ferrous sulfate) taken with Vitamin C (ascorbic acid) to enhance absorption. Take on an empty stomach.
- IV Iron (for severe cases, intolerance to oral, or malabsorption)
- Identify and treat the underlying cause of bleeding (e.g., Colonoscopy for men/postmenopausal women)
Complications
- Severe fatigue impairing quality of life
- Heart failure (high-output, due to severe anemia)