MS-2910

MS-2910

A 35-year-old woman visits her GP complaining of fatigue and difficulty breathing. She has a medical history of hypothyroidism and rheumatoid arthritis. Upon examination, her blood tests reveal the following results: Hb 102 g/L (normal range for females: 115-160 g/L), B12 650 pg/mL (normal range: 150-900 pg/mL), MCV 110 fl (normal range: 80-100 fl), platelets 324 * 109/L (normal range: 150-400 * 109/L), and WBC 6.8 * 109/L (normal range: 4.0-11.0 * 109/L). A blood film confirms the presence of megaloblastic anemia. What is the most probable underlying cause of the patient’s anemia?