CLINICAL-SIGNIFICANCE OF SERUM VITAMIN-B12 MEASURED BY RADIOASSAY USING PURE INTRINSIC-FACTOR
- 1 January 1981
- journal article
- research article
- Vol. 22 (5) , 447-451
Abstract
Serum vitamin B12 levels of 53 patients (15 pernicious anemia) and 42 healthy volunteers were determined using crude intrinsic factor (IF), pure IF, and a mixture of crude IF + R-protein blocking agent (block IF). The radioassay using pure IF showed less sample-to-sample variation in nonspecific binding than the radioassay using block IF. The mean B12 levels in 42 healthy subjects were significantly higher with crude IF (449 .+-. 23 pg/ml) than with pure IF (408 .+-. 29 pg/ml) or with block IF (407 .+-. 22 pg/ml). B12 levels were abnormally low in all 15 patients with pernicious anemia by pure IF (< 100 pg/ml), in 14 patients by block IF (< 150 pg/ml) and in only 7 patients by crude IF (< 200 pg/ml). B12 deficiency can be diagnosed more reliably by measuring serum B12 levels with either pure IF or block IF.This publication has 4 references indexed in Scilit:
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