Endogenous Interferences in Clinical Laboratory Tests

1 - Preface [Seite 7]
2 - 1 Accuracy Goals for Laboratory Tests [Seite 13]
2.1 - 1.1 Accuracy and Precision [Seite 13]
2.1.1 - 1.1.1 Definition [Seite 13]
2.1.2 - 1.1.2 Imprecision as a Form of Error [Seite 14]
2.2 - 1.2 Types of Error [Seite 14]
2.2.1 - 1.2.1 Bias [Seite 14]
2.2.2 - 1.2.2 Impact of Bias [Seite 16]
2.3 - 1.3 Interference as a Type of Bias [Seite 18]
2.4 - 1.4 References [Seite 20]
3 - 2 Nature of Interferences [Seite 23]
3.1 - 2.1 Definition [Seite 23]
3.2 - 2.2 Nature of Interferences [Seite 23]
3.3 - 2.3 Instrumentation [Seite 24]
3.4 - 2.4 The Chemistry of the Absorbance of Light [Seite 27]
3.5 - 2.5 References [Seite 32]
4 - 3 The Nature of Icteric Interference [Seite 33]
4.1 - 3.1 Source Information on Bilirubin Interference [Seite 33]
4.2 - 3.2 Allen Correction as a Source of Bilirubin Interference [Seite 33]
4.3 - 3.3 Bilirubin Interference with Oximetry [Seite 34]
4.3.1 - 3.3.1 Co-oximetry Interference [Seite 36]
4.3.2 - 3.3.2 Pulse Oximetry [Seite 37]
4.3.3 - 3.3.3 Cerebral Oximetry [Seite 38]
4.3.4 - 3.3.4 Interference with Methemoglobin [Seite 39]
4.4 - 3.4 Chemical Reactions as a Cause of Bilirubin Interference [Seite 40]
4.4.1 - 3.4.1 Bilirubin Reaction with Creatinine Methods [Seite 41]
4.4.2 - 3.4.2 Bilirubin Reactions with Peroxidase Methods [Seite 43]
4.5 - 3.5 References [Seite 44]
5 - 4 The Nature of Lipemic and Turbidity Interferences [Seite 47]
5.1 - 4.1 Types of Interferences [Seite 47]
5.2 - 4.2 Lipemia Causes Turbidity [Seite 48]
5.3 - 4.3 Lipemia Interference Mechanisms [Seite 49]
5.3.1 - 4.3.1 Light Scattering [Seite 49]
5.3.2 - 4.3.2 Lipoprotein Particles [Seite 52]
5.3.3 - 4.3.3 Intralipid® and Lipemia Simulation [Seite 54]
5.3.4 - 4.3.4 Empirical Studies in Lipemia Turbidity [Seite 55]
5.4 - 4.4 Lipoprotein Particles and Lipemia [Seite 56]
5.5 - 4.5 References [Seite 57]
6 - 5 Measurement of Interference [Seite 59]
6.1 - 5.1 A Typical Commercial Study [Seite 59]
6.2 - 5.2 Guidelines for Interference Studies [Seite 60]
6.3 - 5.3 Bilirubin [Seite 61]
6.4 - 5.4 Intralipid® [Seite 62]
6.5 - 5.5 Procedure to Make Five Concentrations [Seite 64]
6.6 - 5.6 Interference Criteria [Seite 64]
6.7 - 5.7 Data Analysis [Seite 66]
6.8 - 5.8 References [Seite 72]
7 - 6 Origin of Icteric Samples [Seite 75]
7.1 - 6.1 The Origin of Bilirubin [Seite 75]
7.2 - 6.2 Bilirubin Toxicity [Seite 77]
7.3 - 6.3 Transport of Bilirubin in the Blood [Seite 77]
7.4 - 6.4 Uptake of Bilirubin by the Liver [Seite 78]
7.5 - 6.5 Clinical Aspects of Bilirubin [Seite 78]
7.6 - 6.6 Neonatal Jaundice [Seite 79]
7.7 - 6.7 Cholestasis [Seite 81]
7.8 - 6.8 Hepatitis [Seite 82]
7.9 - 6.9 Alcoholic Liver Disease [Seite 82]
7.10 - 6.10 Hemolysis [Seite 83]
7.11 - 6.11 Drug Induced Hyperbilirubinemia [Seite 83]
7.12 - 6.12 Summary [Seite 84]
7.13 - 6.13 References [Seite 84]
8 - 7 Impact of Icterus [Seite 87]
8.1 - 7.1 Introduction [Seite 87]
8.2 - 7.2 Estimated Impacts Based on Interference Studies [Seite 87]
8.3 - 7.3 Differential Interference with Different Bilirubin Isoforms [Seite 89]
8.4 - 7.4 Non-spectrophotometric Icterus Interference [Seite 91]
8.5 - 7.5 Resolving Icterus Interference [Seite 92]
8.6 - 7.6 Summary [Seite 93]
8.7 - 7.7 References [Seite 93]
9 - 8 Origin of Lipemia and Turbidity [Seite 95]
9.1 - 8.1 Lipoprotein Pathways [Seite 95]
9.2 - 8.2 Classification of Hypertriglyceridemia [Seite 97]
9.2.1 - 8.2.1 Frederickson Classification of Dyslipidemias [Seite 97]
9.2.2 - 8.2.2 Obesity, Metabolic Syndrome and Diabetes [Seite 99]
9.2.3 - 8.2.3 Alcohol [Seite 100]
9.2.4 - 8.2.4 Nonalcoholic Fatty-liver Disorder [Seite 101]
9.2.5 - 8.2.5 Medications [Seite 101]
9.2.6 - 8.2.6 HIV Infection [Seite 101]
9.2.7 - 8.2.7 Renal Disease [Seite 102]
9.3 - 8.3 References [Seite 103]
10 - 9 Impact of Lipemia/Turbidity [Seite 105]
10.1 - 9.1 Introduction [Seite 105]
10.2 - 9.2 Estimated Impacts Based on Interference Studies [Seite 107]
10.2.1 - 9.2.1 Interference by Light Scattering [Seite 107]
10.2.2 - 9.2.2 Interference by Volume Displacement [Seite 108]
10.2.3 - 9.2.3 Interference by Lipid Partitioning [Seite 111]
10.3 - 9.3 Summary [Seite 111]
10.4 - 9.4 References [Seite 111]
11 - 10 Endogenous Interferences in Clinical Laboratory Tests: Icteric, Lipemic and Turbid Samples [Seite 113]
11.1 - 10.1 Interference Indices [Seite 113]
11.2 - 10.2 Generating Interference Indices [Seite 113]
11.2.1 - 10.2.1 Preparation of Standards [Seite 114]
11.2.2 - 10.2.2 Data Collection and Deconvolution of Non-Target Interferences [Seite 115]
11.2.2.1 - 10.2.2.1 Subtraction Using Selected Wavelengths [Seite 116]
11.2.2.2 - 10.2.2.2 Index Calculation Using Derivative Spectrometry [Seite 117]
11.2.3 - 10.2.3 Establishing Indices and Defining Ranges [Seite 119]
11.3 - 10.3 Limitations [Seite 122]
11.4 - 10.4 Summary [Seite 122]
11.5 - 10.5 References [Seite 123]
12 - 11 Reporting of Results [Seite 125]
12.1 - 11.1 Introduction [Seite 125]
12.2 - 11.2 Procedures for Handling Samples with Interference Within the Laboratory [Seite 125]
12.3 - 11.3 Reporting of Results in Icteric and Turbid Samples [Seite 127]
12.4 - 11.4 Autoverification and Reporting Algorithms [Seite 128]
12.5 - 11.5 Practical Issues: Education and Implementation [Seite 129]
12.6 - 11.6 References [Seite 130]
13 - 12 Analyte-dependent Interference [Seite 131]
13.1 - 12.1 Complex Interferences [Seite 131]
13.1.1 - 12.1.1 Model for Analyte-dependent Interference [Seite 132]
13.1.2 - 12.1.2 Examples of Analyte-Dependent Interference [Seite 133]
13.2 - 12.2 Statistical Testing for Significance [Seite 141]
13.3 - 12.3 Failure to Design the Interference Study [Seite 145]
13.4 - 12.4 Advantages of Using Multiple Regression Analysis [Seite 145]
13.5 - 12.5 Concluding Remarks [Seite 147]
13.6 - 12.6 References [Seite 149]
14 - Index [Seite 151]