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Mapping Metabolism: Monitoring Lactate Dehydrogenase Activity Directly in Tissue
Published on: June 21, 2018
Artifactually elevated serum bicarbonate results caused by elevated serum lactate dehydrogenase concentrations
Mohamed Saleem1, Goce Dimeski, Les Bourne
1Department of Clinical Biochemistry, IMVS/SA Pathology, Adelaide, South Australia. Mohamed.Saleem@health.sa.gov.au
Annals of Clinical Biochemistry
|April 23, 2013
Summary
Elevated lactate dehydrogenase (LD) levels can interfere with serum bicarbonate (HCO3(-)) measurements on the Olympus AU2700 analyzer. This interference, particularly with older reagents, can lead to inaccurate results in clinical diagnostics.
Area of Science:
- Clinical Chemistry
- Diagnostic Assay Development
- Biochemical Interference Studies
Background:
- Accurate serum bicarbonate (HCO3(-)) measurement is critical for diagnosing acid-base and electrolyte imbalances.
- Discrepancies were observed between Olympus AU2700 and Radiometer blood gas analyzer bicarbonate (HCO3(-)) and total carbon dioxide (TCO2) measurements.
- Manufacturer recall of specific reagent lot numbers indicated a potential issue with the Olympus AU2700 bicarbonate assay.
Purpose of the Study:
- To investigate the cause of discrepancies in serum bicarbonate (HCO3(-)) measurements on the Olympus AU2700 analyzer.
- To test the hypothesis that elevated lactate dehydrogenase (LD) levels interfere with the Olympus AU2700 bicarbonate (HCO3(-)) assay.
- To compare the performance of a recalled reagent lot with an unaffected lot in the presence of varying LD concentrations.
Main Methods:
- Experimental investigation of serum bicarbonate (HCO3(-)) assay performance on the Olympus AU2700 analyzer.
- Utilized a recalled reagent lot and a subsequent unaffected reagent lot for comparative analysis.
- Assessed the effect of increasing lactate dehydrogenase (LD) concentrations on bicarbonate (HCO3(-)) measurements.
Main Results:
- Confirmed positive interference in the Olympus AU2700 bicarbonate (HCO3(-)) assay with older reagent lot numbers.
- Significant false positive bicarbonate (HCO3(-)) interference (>10% change) occurred when LD levels exceeded 845 U/L.
- The interference was dependent on the reagent lot number used.
Conclusions:
- Very high lactate dehydrogenase (LD) concentrations are identified as the cause of interference in the Olympus AU2700 bicarbonate (HCO3(-)) enzymatic assay.
- Laboratorians should be aware of potential interference from extremely high LD levels in certain enzymatic bicarbonate (HCO3(-)) assays.
- This finding highlights the importance of considering enzyme levels when interpreting bicarbonate (HCO3(-)) results from automated analyzers.
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