Effect of Hemolysis, High Bilirubin, Lipemia, Paraproteins, and System Factors on Therapeutic Drug Monitoring

摘要: Among the endogenous interferents affecting assay results, most common are bilirubin, hemoglobin, lipids, and paraproteins. These may affect therapeutic drug monitoring (TDM), drugs of abuse (DAU) testing, toxicology assays any format where sample is used directly for analysis without pretreatment specimen. Immunoassays commonly in clinical laboratories analyte-specific antibody or binding agents to estimate analyte concentration Some enzyme chemistry also utilized TDM DAU analysis. Such use various types signals, being colorimetry, fluorimetry, chemiluminescence. Assays be prone interference depending on label used. Commercial kits report result such kit inserts (up levels >20 mg/dL >500 >1000 lipids). The caused by optical, fluorescent, chemiluminescent properties these interferents. Thus, bilirubin interferes its absorption fluorescence properties, hemoglobin absorption, chemiluminescence lipids interfere mostly from their light-scattering (turbidity) properties. Bilirubin because side reactions assay. Modern auto-analyzers can detect all three flag results. Flagged results should carefully reviewed accuracy. Both hypo- hyper-proteinemia Paraproteins many precipitating out during blanking step thus producing false Another source probe (sample reagents) reaction cuvettes carryover contamination random-access auto-analyzers. If validity test questioned, repeated either removing interferent using different method which known suffer less that type interference.