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Clinical manifestations and diagnosis of vitamin B12 and folate deficiency

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


This topic review discusses the symptoms, clinical manifestations, and diagnosis of vitamin B12 and folate deficiency, vitamins that are required for normal hematopoiesis and neurologic function. Vitamin B12 and folate deficiencies are often considered together, although folate deficiency has become exceedingly rare in individuals who are living in developed countries and consuming a normal diet.

Separate topic reviews discuss the treatment of these deficiencies, their causes and pathophysiology, and other causes of macrocytic anemia:

Treatment – (See "Treatment of vitamin B12 and folate deficiencies".)

Pathophysiology – (See "Causes and pathophysiology of vitamin B12 and folate deficiencies".)

Other macrocytic anemias – (See "Macrocytosis/Macrocytic anemia".)

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Literature review current through: Nov 2017. | This topic last updated: Jun 28, 2017.
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