Folate deficiency - Symptoms, Causes, Images, and Treatment Options

Diseases

Highlights & Basics

Key Highlights

Folate deficiency classically presents as megaloblastic anemia, with absence of neurologic signs.
Common causes include malabsorption, drugs and toxins, states of increased demand, and dietary deficiency. Hereditary folate malabsorption and other inborn errors of folate metabolism are rare causes.
In early disease, hemoglobin and mean corpuscular volume are normal. In severe disease, patients present with symptomatic anemia and pancytopenia.
Maternal folate deficiency is associated with fetal neural tube defects (NTDs).
Diagnosis is confirmed by the presence of low serum folate and/or low red blood cell folate. Elevated plasma homocysteine levels are helpful in situations of diagnostic difficulty.

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History & Exam
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Definition

Epidemiology

Etiology

Pathophysiology

Images

Megaloblastic macrocytic anemia: A. Peripheral blood smear of a patient with megaloblastic anemia. B. Peripheral blood smear of healthy individual
Angular cheilitis
Megaloblastic marrow cells

Citations

Key Articles

Pfeiffer CM, Sternberg MR, Zhang M, et al. Folate status in the US population 20 y after the introduction of folic acid fortification. Am J Clin Nutr. 2019 Nov 1;110(5):1088-97.[Abstract][Full Text]
Wickramasinghe SN. Diagnosis of megaloblastic anaemias. Blood Rev. 2006 Nov;20(6):299-318.[Abstract]
Allen LH. Causes of vitamin B12 and folate deficiency. Food Nutr Bull. 2008 Jun;29(2 suppl):S20-34.[Abstract]
Whitehead VM. Acquired and inherited disorders of cobalamin and folate in children. Br J Haematol. 2006 Jul;134(2):125-36.[Abstract][Full Text]
MRC Vitamin Study Research Group. Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. Lancet. 1991 Jul 20;338(8760):131-7.[Abstract]
Institute of Medicine. Dietary reference intakes for thiamine, riboflavin, niacin, vitamin B6, folate, vitamin B12, pantothenic acid, biotin, and choline. Washington, DC: National Academy Press; 1998.

Other Online Resources

US Department of Agriculture and US Department of Health and Human Services: dietary guidelines for Americans, 2020-2025
NIH: dietary supplement fact sheet - folate

Referenced Articles

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