Article

Unbound iron binding capacity (UIBC) as a test for empty iron stores - results from the HUNT Study.

Department of Clinical Chemistry, Trondheim University Hospital , Trondheim , Norway.
Scandinavian journal of clinical and laboratory investigation (Impact Factor: 2.01). 08/2012; 72(6):506-9. DOI: 10.3109/00365513.2012.713230
Source: PubMed

ABSTRACT Abstract Background. When s-iron and s-transferrin are used to diagnose empty iron stores, the measurements are usually combined in the calculation of s-transferrin saturation. This may not be the best way to utilize the information in s-iron and s-transferrin, as s-transferrin alone has a better diagnostic accuracy than s-transferrin saturation. We suggest that unbound iron binding capacity (UIBC), which is s-total iron binding capacity (2 times s-transferrin) minus s-iron could be used for diagnosing empty iron stores. Methods. To test this hypothesis, we used ROC curve analysis to compare the diagnostic accuracy of s-iron, s-transferrin, s-transferrin saturation and s-UIBC in diagnosing empty iron stores in 3029 women of childbearing age. Empty iron stores were defined as s-ferritin less than 10 μg/L or less than 15 μg/L. Results. At both definitions of empty iron stores s-UIBC had a better diagnostic accuracy than the other tests, with area under the ROC curve of 0.80-0.87. This was also the trend in a subpopulation of 172 anemic women, where the area under the ROC curve of s-UIBC was 0.92. Conclusion. When diagnosing empty iron stores calculation of s-UIBC is a better way to utilize the information in s-iron and s-transferrin than is calculation of s-transferrin saturation.

3 Followers
 · 
438 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background. Unbound iron binding capacity (UIBC) in serum, which is s-total iron binding capacity (2 times s- transferrin) minus s-iron, may be a more accurate marker of empty iron stores than serum transferrin saturation. Previously we have shown this for healthy females of childbearing age. Methods. Now we used receiver operating characteristic (ROC) curve analysis to compare the diagnostic accuracy of s-iron, s-transferrin, s-transferrin saturation and s-UIBC in diagnosing empty iron stores in 29,251 female and 19,652 male outpatients. Empty iron stores were defined as s-ferritin less than 10, 15 or 20 μg/L. Results. At all definitions of empty iron stores s-UIBC had a better diagnostic accuracy than the other tests in both male and female outpatients, with an area under the ROC curve of 0.85-0.97. Also in subpopulations with elevated s-CRP or low b-hemoglobin s-UIBC was more accurate than the other tests. All tests performed better in males than in females, and generally they were more accurate in adults than in children. Conclusion. When diagnosing empty iron stores calculation of s-UIBC is a better way to utilize the information in s-iron and s-transferrin than the calculation of s-transferrin saturation.
    Scandinavian journal of clinical and laboratory investigation 02/2013; DOI:10.3109/00365513.2013.765029 · 2.01 Impact Factor

Preview

Download
23 Downloads