system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 44-year-old woman is brought to the emergency department because of confusion and agitation. She was brought by police after she was found walking along a highway. The patient's brother comes to join her soon after her arrival. He says she has peptic ulcer disease and hypertension. He thinks she drinks around half a bottle of vodka daily. Her current medications include omeprazole and hydrochlorothiazide, although the brother is unsure if she takes them regularly. Her temperature is 37.1°C (98.7°F), pulse is 90/min, respirations are 16/min, and blood pressure is 135/90 mm Hg. On mental status examination, she is confused and not oriented to person, place, or time. Neurologic examination shows horizontal nystagmus. Her gait is wide-based with small steps. Her hemoglobin concentration is 9 g/dL. Her serum homocysteine concentration is elevated and her methylmalonic acid concentration is within the reference range. A peripheral blood smear shows hypersegmented neutrophils. Which of the following is the most likely cause of this patient's anemia?
assistant
Folate deficiency