Reducing Specimen Rejection Rates Using Concentration-Dependent Hemolysis Rejection Thresholds
Nga Yeung Tang1,2,3, Kelly R Mitchell4, Sarah E Groboske4
1Department of Pathology, The University of Chicago, Chicago, IL.
Background:
Using middleware solutions, it is possible to implement concentration-dependent analyte-specific hemolysis rejection limits. This makes day-to-day reporting of clinical specimens more efficient and potentially lowers sample rejection rates compared to a "one-size-fits-all" approach (i.e., solely based on a single cutoff provided in the package insert).
Methods:
Hemolysis interference studies were performed at multiple analyte concentrations for three frequently ordered tests. For each assay, concentration-dependent hemolysis rejection limits were designed based on the total allowable error (TAE) for the analyte as well as the clinical significance of such incurred inaccuracy at the respective concentrations. In general, the following rationale was used: if the interference exceeds 10% (or package insert cutoffs), a comment is placed on the result. If the interference exceeds the TAE, the result will not be reported. Reduction in specimen rejection rates were estimated by comparing the incurred specimen rejection rates when package inserts' vs concentration-dependent hemolysis interference limits were applied to a data set in our institute during a three-month period.
Results:
Concentration-dependent analyte-specific hemolysis rejection thresholds were designed for three commonly ordered assays that are especially susceptible to hemolysis interference. It is estimated that these novel thresholds for aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and direct bilirubin (DBIL) reduced specimen rejection rates from 9.3% to 1.3%, 31.4% to 4.8%, and 19.9% to 7.1%, respectively.
Conclusions:
Concentration-dependent analyte-specific hemolysis rejection thresholds for three commonly ordered assays can reduce rejection rates without significantly compromising the quality of test results.
Insights
Implementing concentration-dependent hemolysis rejection limits for clinical assays significantly reduces sample rejection rates. This tailored approach improves efficiency and maintains test result quality compared to standard cutoffs.
Area of Science:
- Clinical Chemistry
- Laboratory Medicine
- Biomedical Engineering
Background:
- Hemolysis is a common interference in clinical laboratory testing.
- Standardized rejection limits may lead to unnecessary sample rejections.
- Middleware solutions enable customized, analyte-specific rejection criteria.
Purpose of the Study:
- To develop and evaluate concentration-dependent, analyte-specific hemolysis rejection limits.
- To assess the impact of these novel limits on specimen rejection rates.
- To compare the efficiency of customized limits versus standard package insert cutoffs.
Main Methods:
- Hemolysis interference studies were conducted at various analyte concentrations for three key assays.
- Rejection limits were designed based on total allowable error (TAE) and clinical significance.
- Specimen rejection rates were compared using standard vs. concentration-dependent limits over a three-month period.
Main Results:
- Novel concentration-dependent thresholds were established for aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and direct bilirubin (DBIL).
- These thresholds reduced rejection rates for AST from 9.3% to 1.3%, LDH from 31.4% to 4.8%, and DBIL from 19.9% to 7.1%.
- The implementation demonstrated a substantial decrease in specimen rejection.
Conclusions:
- Concentration-dependent, analyte-specific hemolysis rejection thresholds are effective in reducing specimen rejection rates.
- This approach enhances laboratory efficiency without compromising the quality of diagnostic test results.
- Customized rejection criteria offer a superior alternative to universal cutoffs for hemolysis interference.
