What test is commonly used to evaluate vitamin B12 absorption in patients with pernicious anemia?

What test is commonly used to evaluate vitamin B12 absorption in patients with pernicious anemia?

• A. Complete blood count
• B. Schilling's test
• C. Iron level test
• D. Homocysteine test

Answer: (B)

Schilling's test is specifically designed to assess vitamin B12 absorption, particularly in the context of pernicious anemia. Pernicious anemia is an autoimmune condition where the body is unable to absorb vitamin B12 due to a lack of intrinsic factor, a protein necessary for B12 absorption in the intestine. The test involves administering a small amount of radioactive B12 followed by a shot of intrinsic factor, then measuring the amount of B12 excreted in the urine over a 24-hour period. In healthy individuals, a significant amount of the radioactive B12 would be absorbed and appear in the urine. In patients with pernicious anemia, the absorption will typically be low unless intrinsic factor is provided, reflecting the nature of the disease. The other tests mentioned, while they may provide useful information about anemia or related conditions, do not specifically assess vitamin B12 absorption. A complete blood count evaluates various blood components but does not directly test for vitamin absorption. An iron level test assesses iron deficiency or overload, and a homocysteine test can indicate B12 deficiency but does not measure absorption directly. Thus, Schilling's test remains the definitive test for evaluating B12 absorption in the context of pernicious anemia.

Schilling's test is specifically designed to assess vitamin B12 absorption, particularly in the context of pernicious anemia. Pernicious anemia is an autoimmune condition where the body is unable to absorb vitamin B12 due to a lack of intrinsic factor, a protein necessary for B12 absorption in the intestine.

The test involves administering a small amount of radioactive B12 followed by a shot of intrinsic factor, then measuring the amount of B12 excreted in the urine over a 24-hour period. In healthy individuals, a significant amount of the radioactive B12 would be absorbed and appear in the urine. In patients with pernicious anemia, the absorption will typically be low unless intrinsic factor is provided, reflecting the nature of the disease.

The other tests mentioned, while they may provide useful information about anemia or related conditions, do not specifically assess vitamin B12 absorption. A complete blood count evaluates various blood components but does not directly test for vitamin absorption. An iron level test assesses iron deficiency or overload, and a homocysteine test can indicate B12 deficiency but does not measure absorption directly. Thus, Schilling's test remains the definitive test for evaluating B12 absorption in the context of pernicious anemia.