Iron deficiency anemia

Etiology of iron deficiency

• Hemorrhage (most common)
  • Gastrointestinal (NSAIDs etc)
  • Urogenital (hematuria)
  • Respiratory (hemoptysis)
  • Trauma (and surgery)
  • Blood donations
  • Blood loss leading to iron deficiency is almost always clinically inapparent
• Increased iron demand with inadequate supply
  • Adolescence
  • Pregnancy
  • Breastfeeding
  • Increased erythropoiesis in the course of treatment of VB12 deficiency
• GI malabsorption
  • Bariatric surgery
  • H pylori infection
  • Autoimmune gastritis
  • Celiac disease
  • Intestinal resection
  • Low-protein diet
  • High intake of substances that decrease iron absorption
• Low dietary iron
  • Vegetarian/vegan
• Iron-refractory iron deficiency anemia (IRIDA) a rare AR disorder
• Chronic gastric acid suppression
  • PPI etc

Clinical Features

• Systemic manifestations of anemia
• Signs and symptoms of chronic iron deficiency
  • Perverted appetite (pica)
  • Pain/tingling and smoothing of the tongue
  • Dry skin
  • Painful cheilosis
  • Nail and hair abnormalities (pale, fragile, longitudinal stripes and furrows; fine, fragile, split ends)
• Underlying condition eg CRC

Treatment

• Treat the underlying cause
• Iron replacement therapy to restore normal serum ferritin levels
  • No known malabsorption:
    • Oral iron elemental form or fixed combinations or iron and ascorbic acid
    • Avoid long-term gastric acid suppression therapy
    • Should increase reticulocytes within 5-10 days and Hb should slowly increase after 1-2 weeks of therapy
  • Intolerance or refractory to PO iron, treated with an ESA in setting of chemotherapy, malabsorption, IBD, chronic inflammatory disease, CKD:
    • IV iron
    • Iron infusions have risk of severe hypersensitivity reaction
• Pregnant and breastfeeding women should have prophylactic iron, 30 mg/d and 100-200 mg/d if deficient
• PRBC if severe and symptomatic