Blood/Blood Cells and Cellular Components ›› Red Blood Cells ›› Abnormal

Macrocytic RBC: MCV >100*

Microscopic Features:
  • Slightly larger than a normal mature RBC which correlates to the MCV of >100 fL
  • Round to oval in shape (lacks a nucleus similar to the normal RBC)
  • Cytoplasm is pink-orange in color wth a central pallor (similar to a normal RBC)
Normal % blood-PB, marrow-BM, lymphoid tissue-LN:
  • PB: Rare to None
  • BM: Rare to None
  • LN: Rare to None
May Resemble:
  • Normal Mature RBC
  • Polychromatophilic RBC
  • Giant platelet (specially if hypogranular)
  • Elliptocyte (ovalocyte)
Differential Diagnoses:

Vitamin B12 or folate deficiency
Chemotherapy (e.g. Methotrexate)
Liver disease
Thyroid disease

Classic Immunophenotype:
  • N/A
Cartoon Image:

  • Must rule out B12 or Folate deficiency