Final answer:
The Schilling test was traditionally used to diagnose pernicious anemia by measuring the urinary excretion of orally administered radioactive vitamin B12, but modern diagnosis primarily relies on blood tests.
Step-by-step explanation:
The unique urine test done to diagnose pernicious anemia is not the Benedict's test, Bence Jones proteinuria, or the pancreolauryl test. These tests are respectively used for detecting diabetes mellitus through glucose presence, the presence of Bence Jones proteins in conditions such as multiple myeloma, and assessing pancreatic exocrine function. Pernicious anemia, which is caused by poor absorption of vitamin B12, is often associated with conditions that affect the gastrointestinal tract such as Crohn's disease, surgical removal of parts of the intestine, or other disorders that interfere with nutrient absorption.
To diagnose pernicious anemia, a Schilling test used to be the standard, which involved the oral administration of radioactive vitamin B12 and measurement of its absorption by analyzing subsequent urinary excretion. However, this test has become less common due to advancements in medical diagnostics. Modern diagnosis now involves blood tests to measure levels of vitamin B12, methylmalonic acid, homocysteine, and intrinsic factor antibodies.