Proposed reference method for iron in serum used to evaluate two automated iron methods.

Area of Science:

• Clinical Chemistry
• Analytical Biochemistry
• Laboratory Medicine

Background:

• Accurate serum iron measurement is crucial for diagnosing and monitoring various medical conditions.
• Existing reference methods require validation against novel automated and dry-film technologies for clinical use.

Purpose of the Study:

• To evaluate the performance of two working methods for serum iron determination against a standard reference method.
• To assess the reliability and potential interferences of automated and dry-film based iron assays.

Main Methods:

• Comparison of a detergent solubilization method on the Roche Cobas-Bio analyzer and a dry-film method on the Kodak Ektachem 700 against the manual Centers for Disease Control Reference Method for serum iron (CDC/RM/Fe) and its semiautomated adaptation.
• Analysis of sera from 40 hospital patients for initial comparison, followed by a larger study involving 200 patients.
• Inclusion of separate recovery and interference studies to assess analytical performance.

Main Results:

• The semiautomated CDC/RM/Fe method demonstrated comparable results to the manual reference method.
• Both the Roche Cobas-Bio and Kodak Ektachem 700 methods showed good correlation with the semiautomated CDC/RM/Fe method.
• Satisfactory analytical recovery of iron was observed for all methods, but the detergent solubilization method exhibited interference from hemoglobin, lipemia, and bilirubin.

Conclusions:

• Both evaluated working methods for serum iron analysis are reliable and correlate well with the CDC reference method.
• The detergent solubilization method requires caution due to potential interference from common biological substances.
• Further validation is recommended for the detergent solubilization method in the presence of hemoglobin, lipemia, or bilirubin.