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Microcytosis/Microcytic anemia

Stanley L Schrier, MD
Section Editor
William C Mentzer, MD
Deputy Editor
Jennifer S Tirnauer, MD


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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Literature review current through: Nov 2017. | This topic last updated: Jul 29, 2016.
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