Kroll / McCudden Endogenous Interferences in Clinical Laboratory Tests

Icteric, Lipemic and Turbid Samples
1. Auflage 2012
ISBN: 978-3-11-026622-1
Verlag: De Gruyter
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, Band 5, 155 Seiten

Reihe: Patient Safety

The goal of clinical laboratories is to produce accurate information for clinical decision making in medicine. More than half of the medical decisions made depend on clinical laboratory tests.

Patient safety represents an important and critical problem for laboratories. They need to assure that the information they deliver to physicians is accurate, and therefore safe for clinicians to use. Endogenous compounds can interfere with laboratory tests, decreasing accuracy and threatening patient safety. Elevated bilirubin (bilirubinemia) and elevated lipids (lipemia) are common conditions that cause significant interferences with laboratory results. Clinicians depend on laboratories to detect these endogenous interferences. Laboratories must have a means to detect these endogenous interferences, make decisions about reporting results, and evaluate their impact.

Most clinical pathology books provide only an abbreviated introduction to the subject, or provide a long list of references, without the necessary foundation for evaluating their significance. Package inserts typically provide scant information. This book provides the empirical and theoretical foundation for these interferences, describes the clinical settings where they occur, and explains their evaluation and detection, allowing the laboratory to interpret the available data on interferences and make the appropriate decision to effectively report test results while protecting patient safety.

Zielgruppe

Physicians, Clinical Biochemists, Research Scientists, Laboratory

Autoren/Hrsg.

Kroll, Martin H.

McCudden, Christopher R.

Fachgebiete

• Medizin | Veterinärmedizin Medizin | Public Health | Pharmazie | Zahnmedizin Medizinische Fachgebiete Pathologie, Cytopathologie, Histopathologie
• Medizin | Veterinärmedizin Medizin | Public Health | Pharmazie | Zahnmedizin Medizin, Gesundheitswesen Labormedizin

Inhaltsverzeichnis

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

Über Autor(innen)

Martin H. Kroll, Boston University, Massachusetts, USA; Christopher R. McCudden, University of Ottawa, Ontario, Canada; University of North Carolina at Chapel Hill, USA.