Red Blood Cell Morphology Quiz

Red Blood Cell (RBC) Morphology

• Burr Cell (A.K.A. Crenated Cell / Echinocyte):

  • RBCs with regularly spiculated surfaces
  • May exhibit even projections or a rounded appearance

• Ovalocyte:

  • Oval-shaped RBCs
  • Associated with hereditary ovalocytosis (aka South East Asian ovalocytosis)
  • Also linked to pyruvate kinase deficiency

• Elliptocyte:

  • Elliptical (cigar-shaped) RBCs
  • Linked to hereditary elliptocytosis
  • Can be associated with thalassemia and/or mediterrannean anemia.

• Dacryocyte (A.K.A. Tear Drop Cell):

  • Pear-shaped or teardrop-shaped RBCs
  • Frequently found in primary myelofibrosis (PMF)
  • PMF is a type of myeloproliferative neoplasm. Characteristics include: splenomegaly, marrow hypercellularity with increased megakaryocytes and fibrosis, immature granulocytes, normoblasts, dacryocytes, and other bizarre RBC shapes in the peripheral blood smear (PBS).

• Schistocyte (A.K.A. Schistocyte):

  • Fragmented RBCs
  • Associated with conditions like patients with artificial heart valves, uremia, severe burns, certain microangiopathic hemolytic anemias (e.g., TTP, HELLP syndrome, HUS) and disseminated intravascular coagulation (DIC)

Other Conditions

• Uremia:

  • Characterized by elevated plasma urea and other nitrogenous waste products
  • Often results in acidemia, electrolyte imbalance (potassium elevation), normocytic and normochromic anemia, uremic frost, generalized edema, foul breath, and urine-like sweat.

• Primary Myelofibrosis (PMF):

  • A myeloproliferative neoplasm (MPN)
  • Splenomegaly, hypercellularity, increased megakaryocytes and fibrosis in the bone marrow; and immature granulocytes, normoblasts, and dacryocytes, and other bizarre RBC shapes in the peripheral blood smear (PBS).
  • PMF was previously known as myelofibrosis with myeloid metaplasia, chronic idiopathic myelofibrosis, and agnogenic myelofibrosis.

• Megaloblastic Anemia:

  • Associated with myelophthisic anemia, Heinz body formation, drug /toxin ingestion, and some hemolytic conditions.

• HUS (Hemolytic Uremic Syndrome):

  • Characterized by renal failure, thrombocytopenia, presence of schistocytes in the peripheral blood smear (PBS), and severe mucocutaneous hemorrhage.
  • Often associated with Escherichia coli serotype O157: H7 infection.