A 45-year-old Caucasian female presents to your office with abdominal discomfort and distention that is especially bothersome after meals. She has noticed recently that she gets tired more easily. She feels "down", but denies any sleep difficulty, crying spells and suicidal ideation. She visited a doctor approximately one year ago due to similar complaints, and was told that the problem was psychological. She underwent myomectomy for a large uterine fibroid 8 years ago. She is not sexually active. Her family history is significant for pancreatic cancer in her father and a thyroid disease in her mother. The physical examination is significant for mild pallor of the conjunctivae. The abdomen is somewhat distended with no palpable masses. The laboratory values are: What is the best next step in the management of this patient?

Question

A 45-year-old Caucasian female presents to your office with abdominal discomfort and distention that is especially bothersome after meals.  She has noticed recently that she gets tired more easily.  She feels "down", but denies any sleep difficulty, crying spells and suicidal ideation.  She visited a doctor approximately one year ago due to similar complaints, and was told that the problem was psychological.  She underwent myomectomy for a large uterine fibroid 8 years ago.  She is not sexually active.  Her family history is significant for pancreatic cancer in her father and a thyroid disease in her mother.  The physical examination is significant for mild pallor of the conjunctivae.  The abdomen is somewhat distended with no palpable masses.  The laboratory values are:   What is the best next step in the management of this patient?

Quizplus · Accepted Answer

Explanation: This patient's findings (macrocytic anemia with a normal serum folate level and severely depressed serum cobalamin level) suggest the presence of B12-deficiency anemia. Accompanying gastrointestinal symptoms may indicate pernicious anemia as the cause of the problem. Pernicious anemia is characterized by the autoimmune destruction of parietal cells. The two major implicated auto-antibodies that have been described are the anti-parietal and anti-intrinsic factor (IF) antibodies. Anti-IF antibody testing is the recommended initial test for the detection of pernicious anemia. (Choice D)Anti-IF antibody testing has 50 to 84% sensitivity and almost 100% specificity in detecting pernicious anemia; anti-parietal testing is much less specific. (Choice A)Schilling test is a classic diagnostic test of pernicious anemia that uses radio-labeled cobalamin. It is more cumbersome than antibody testing, and can be used as the second-line test if the anti-IF test is negative. (Choice B)Patients with pernicious anemia are typically achlorhydric, but measurement of gastric secretions is generally not performed because it is highly invasive and non-specific. (Choice E)Bone marrow biopsy can confirm the diagnosis of megaloblastic anemia, but is also highly invasive and non-specific for the underlying cause of the problem. Educational objective: Anti-IF antibody testing has 50 to 84% sensitivity and almost 100% specificity in detecting pernicious anemia. It is the recommended initial diagnostic test.

A 45-Year-Old Caucasian Female Presents to Your Office with Abdominal