A 28-year-old man of Mediterranean descent presents to the emergency department with dark urine, jaundice, and fatigue two days after consuming a meal containing fava beans. He denies fever, chills, or recent illness but reports that similar symptoms occurred once before after taking an unknown medication. His physical examination reveals pallor, scleral icterus, and mild splenomegaly. Laboratory tests show: Hemoglobin: 8.5 g/dL (low) Reticulocyte count: Elevated Indirect bilirubin: Elevated Peripheral smear: Presence of Heinz bodies and bite cells Question: Which of the following is the most likely underlying cause of this patient’s condition?
