A Patient presents with macroglossia and loss of tongue papilla. His hemoglobin (Hb) is 11.5 and mean corpuscular volume (MCV) is 100. What should be the next step in investigating this patient?
High-Yield Explanation
Increased MCV (normal MCV = 79- 93.3), anemia (normal Hb = 12--16.2) and characteristic oral manifestation (macroglossia and Atrophy of Papillae) suggest the diagnosis of megaloblastic anemia. The next best step is to confirm the diagnosis by estimating vitamin B12 levels and folate levels. So B12 estimation is the single best answer of choice. Ref: Harrison's Principles of Internal Medicine, 16th Edition, Pages 602-03; Davidson's Principles and Practice of Medicine, 19th Edition, Pages 918-20; Manual of Practical Medicine By R Alagappan, 3rd Edition, Pages 327-29