Review Question - QID 104652

This woman is most likely deficient in folate given her fatigue, pallor, and megaloblastic anemia.

Folic acid deficiency is common in the elderly, who sometimes subsist on a "tea and toast" diet. Other vulnerable groups include patients with the following risk factors: alcoholism, gastrointestinal disease (such as celiac disease, inflammatory bowel disease, or short bowel syndrome), pregnancy, increased cell turnover, and medications that inhibit folate metabolism (such as methotrexate, phenytoin, and sulfasalazine). Folate deficiency presents with a megaloblastic anemia. Although this deficiency can present with similar findings to vitamin B12 deficiency, it does not cause neurological deficits while B12 deficiency does. Similarly, folate is rapidly depleted and is the most common cause of a macrocytic anemia whereas vitamin B12 takes much longer to become depleted.

Incorrect answers:
Answer 2: Niacin deficiency causes pellagra which presents with diarrhea, dermatitis, dementia, and death if untreated.

Answer 3: Thiamine deficiency presents with Wernicke-Korsakoff syndrome which presents with ataxia, nystagmus, and ophthalmoplegia which can progress to psychosis.

Answer 4: Vitamin B12 deficiency presents with a megaloblastic anemia and signs of dorsal column dysfunction (impaired proprioception/vibration sensation). This woman's fall may be due to dorsal column dysfunction and impaired proprioception; however, her diet of canned meats and the vast stores of vitamin B12 make this a less likely diagnosis.

Answer 5: Zinc deficiency presents with impaired wound healing.

Bullet Summary:
Folate deficiency is a common cause of a megaloblastic anemia.