Hypoperliferative Anemia With an Elevated McV?

Jordan: Let's suppose we have a 40 year old man who comes into the emergency department with altered mental status. He was brought in by ambulance after experiencing severe right upper quadrant pain at home today. The patient has a known history of rheumatoid arthritis, vitiligo and alcohol use disorder and drinks 5 to 6 drinks daily. Blood labs come back with a low hemoglobin of 9.4, normal reticulocytes and an MCV of 104. What would be on your differential for a patient like this? Thanks Jordan. We do think about those two nutritional deficiencies is causing a macrocytic anemia. How can you potentially differentiate between the two either based on history