- Stanley L Schrier, MD
Stanley L Schrier, MD
- Editor-in-Chief — Hematology
- Section Editor — Myeloproliferative Disorders; Red Blood Cell Disorders
- Professor of Medicine
- Stanford University School of Medicine
Microcytosis is a descriptive term for red blood cell (RBC) size smaller than the normal range. The causes are numerous, and the evaluation depends on a synthesis of clinical and laboratory information.
This topic discusses causes of microcytosis and microcytic anemia. Additional topics discuss the following:
●Macrocytosis/macrocytic anemia – (See "Macrocytosis/Macrocytic anemia".)
●General anemia evaluation
•Child – (See "Approach to the child with anemia".)
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- ASSESSMENT OF RBC SIZE
- MCV (cell volume)
- RDW (size variability)
- Peripheral blood smear review
- CAUSES OF MICROCYTOSIS
- Iron deficiency anemia
- Anemia of chronic inflammation
- Rare causes
- APPROACH TO THE EVALUATION
- Confirm microcytosis/microcytic anemia
- Eliminate iron deficiency and thalassemia
- Assess the likelihood of anemia of chronic inflammation
- Additional evaluations
- SOCIETY GUIDELINE LINKS
- SUMMARY AND RECOMMENDATIONS