Schilling's test is false +ve in -

Ans. is 'b' i.e., Renal insufficiency Schilling test o The Schilling's test is a medical investigation used in patients with Vitamin B,2 deficiency. o The purpose of the test is to determine if the patient has pernicious anemia. o Schilling test is done in two pas - 1. Pa 1 oral Vs intramuscular o In the first pa, radiolabeled vitamin B,2 is given orally. o At the same time intramuscular unlabeled vitamin 1312 is given to saturate tissue stores with normal B12 so that radiolabeled vitamin (which is given orally) cannot bind to body tissues, and if absorbed, it will pass into urine. o Normally, the ingested radiolabeled vitamin B1, will be absorbed into the body. Since the body already has liver receptors for vitamin B12 saturated by injected unlabeled vitamin B12,much of the radiolabeled vitamin B12 is excreted into urine --> (i) Normally 8-10% of radiolabeled Vit. B12 is excreted in urine over the first 24 hours. (ii) In patients with pernicious anemia or with deficiency due to impaired absorption, less than 8% of the radiolabeled vitamin 1312 is detected. 2. Pa 2 Vitamin B12 Vs intrinsic factor o If an abnormality is found in pa 1, the test is repeated, this time with additional oral intrinsic factor :o This is done to differentiate between pernicious anemia (lack of intrinsic factor) from malabsorption. (i) If this time >8-10% of radiolabeled vitamin B pis detected --> there is lack of intrinsic factor production or pernicious anemia. (ii) If test is abnormal this time also there is abnormal intestinal absorption due to any cause of malabsorption.