II. Epidemiology
- Rare in the United States due to fortified cereals
- However, due to minimal Folate stores, acute conditions may rapidly deplete Folic Acid
III. Causes
- Inadequate Folate intake
- Alcohol Abuse
- Elderly
- Vegan diet
- Increased Folate utilization
- Pregnancy
- Malignancy
- Hemolytic Anemia
- Medications
IV. Labs
-
Complete Blood Count
- See Hemoglobin Cutoffs for Anemia
- See Hematocrit Cutoffs for Anemia
-
Macrocytic Anemia (Mean Corpuscular Volume >100 um^3)
- MCV cutoff varies by age and per reference
-
RBC Folate decreased
- Not the same as Serum Folate, which fluctuates considerably with diet
- Serum Vitamin B12 normal
V. Management
- Do not initiate Folate until B12 Deficiency ruled-out
- Folate supplementation masks B12 Deficiency
- Neurologic B12 Deficiency sequelae will progress
-
Folic Acid 1 mg orally daily for 3 weeks or until resolved
- Consider Folic Acid 5 mg orally daily in high utilization states (e.g. acute Hemolytic Anemia)