A 57-year-old man, with a history of chronic alcohol ingestion, is admitted to the hospital with acute alcoholic intoxication and lobar pneumonia. Physical examination reveals pallor; a large, tender liver; and consolidation of the right lower lobe. Laboratory data include hemoglobin of 7 g/dL, WBC of 4000/mL, and platelet count of 85,000/mL. Which of the following is the most likely factor for the anemia?