Anemia

Symptoms

• Lassitude
• Fatigue
• SOBOE
• Palpitations
• Throbbing in head and ears
• Dizziness
• Tinnitus
• Headache
• Dimness of vision
• Insomnia
• Paresthesias
• Angina

Signs

• Tachycardia
• Pallor (skin, MM, conjunctiva, palms)
• Cardiac dilatation
• Systolic flow murmurs
• Edema

1. Is the anemia microcytic, macrocytic, or normocytic?
2. Is pancytopenia present?
3. Is the marrow response appropriate for the anemia as determined by the reticulocyte count?

 

Microcytic (MCV <80fL)

• Fe deficiency
• Globin: Thalassemia
• Prophyrin:
  • Pb poisoning
  • Sideroblastic
• Anemia of chronic disease

Reticulocyte count:

• High: bleeding, hemolysis
• Normal or low:
  • Look at the blood film
    • Hypochromia
    • Target cells – Thalassemias (β – ↑HbA2)
    • Basophilic stipping – Pb poisoning
    • Dimorphic – Sideroblastic
  • Look at the sFe, ferritin and TIBC
    • Fe deficiency: ↓Fe, ↓ferritin and ↑TIBC
    • Thalassemia: normal Fe
    • Sideroblastic: ↑Fe, ↑ferritin
    • ACD: ↓Fe, N/↑ ferritin, ↓TIBC

* Investigate for occult blood loss – i.e. FOB

Normocytic (MCV 80-100fL)

• Bleeding
• Nutritional
• Renal insufficiency
• Hemolysis
• Bone marrow
• Anemia of chronic disease

Reticulocyte count

• Low (underproduction) – look at platelet counts
  • Low (BM: replacement or failure) – Are blasts present?
    • Yes: Leukemia, Metastatic tumor
    • No: Aplastic or hypoplastic anemia, Lipid storage
  • High/Normal: Renal disease, Infection, Chronic disease, Inflammation, Hypothyroidism, Blackfan-Diamond anemia, Transient erythroblastopenia, Congenital dyserythropoietic anemia, Protein malnutrition
• High
  • Blood loss
  • Hemolytic anemia
    • Look at the smear
      • Schizocyte: Intravascular hemolysis
      • Spherocyte: Extravascular hemolysis
      • Sickled cells or Heinz bodies: glucose-6-phosphate-dehydrogenase deficiency
    • Coombs’ test (Ab against Ab on RBC – agglutination)
      • Positive: Isoimmune/Rh/ABO, Incompatible transfusion, Autoimmune hemolytic anemia
      • Negative: Toxic, Infection, Metabolic, Microangiopathic (HUS, DIC), Liver disease

Macrocytic (MCV >100fL)

• Megaloblastic: B₁₂/folate/pernicious
• Alcohol (liver disease)
• Aplastic or hypoplastic anemia
• Hypothyroidism
• Fanconi’s anemia
• Drugs (hydroxyurea, zidovudine)
• Myelodysplasia
• Reticulocytosis

Peripheral smear:

• Large oval red cells (macroovalocytes) and hypersegmented polymorphoneutrophils – Megaloblastosis
• Target cells: Liver disease

LDH: 4-50x normal in Megaloblastic anemia, elevated 2-4x normal in Hemolytic anemia
B₁₂: ↓ in B₁₂ deficiency anemia, normal in Folate deficiency anemia
Folate: ↓ in Folate deficiency anemia, N/↑ in B₁₂ deficiency anemia
Red cell folate: ↓ in Folate deficiency anemia, ↑ in B₁₂ deficiency anemia