Fast Five Quiz: Vitamin B12 Deficiency

Romesh Khardori, MD, PhD


December 22, 2020

According to the AAFP, screening average-risk adults for vitamin B12 deficiency is not recommended. However, screening may be warranted in patients with certain risk factors (eg, gastric or small intestine resection, inflammatory bowel disease, use of certain drugs, age > 75 years).

Initial laboratory assessment should include serum vitamin B12 level and a complete blood cell count. In high-risk patients with low-normal serum levels of vitamin B12, serum methylmalonic acid assessment should be used to confirm vitamin B12 deficiency.

Intramuscular and oral administration of high-dose vitamin B12 (1-2 mg/d) are equally effective for correcting anemia and most neurologic symptoms. However, intramuscular therapy leads to more rapid improvement. Thus, it should be considered in patients with severe neurologic symptoms. Patients who have undergone bariatric surgery should receive oral vitamin B12 supplementation indefinitely.

Read more about the treatment of vitamin B12 deficiency.

This Fast Five Quiz was excerpted and adapted from the Medscape Drugs & Diseases articles Vitamin B-12 Associated Neurological Diseases and Vitamin B Nutritional Disorders.

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