Clinical and Laboratory Evaluation of Specific Chemiluminescence Assays for Intact and Total Proinsulin
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Andreas Pfützner
, Thomas Kunt , Matthias Langenfeld , Mirjam Löbig , Maja Knesovic and Thomas Forst
Abstract
Measurement of proinsulin is an important tool in the assessment of pancreatic β cell function in patients with type 2 diabetes. The goal of this study was to perform a technical and clinical evaluation of two specific chemiluminescence assays (CLIA) for the determination of intact and total proinsulin in comparison to a radioimmunoassay (RIA) method for the measurement of total proinsulin. A total of 191 serum samples from patients with type 2 diabetes were used to perform a regression analysis. The total proinsulin CLIA showed higher proinsulin levels than the two other proinsulin assays (mean ± SD: 55.9±58.1 pmol/l, p < 0.001 in both cases). The intact proinsulin CLIA (22.5±20.9 pmol/l) gave lower values than the RIA for total proinsulin (31.9±25.4 pmol/l, p < 0.001 vs. CLIA, r = 0.948). The RIA has a 95% cross-reactivity to des31,32-proinsulin, which is secreted during the process of β cell deterioration. The intact proinsulin CLIA has virtually no crossreactivity with des31,32-proinsulin (1.4%) and is therefore more specific for intact proinsulin than the RIA. This test does not measure further degradation products, in contrast to the total proinsulin CLIA. The CLIA is, therefore, more specific for total proinsulin measurement than the RIA. Both CLIAs could be performed much faster (4 hours) than the RIA method (75 hours/4 days). In conclusion, the CLIA methods show improved qualitative outcomes, higher specificity and several technical advantages over the RIA method.
Copyright © 2003 by Walter de Gruyter GmbH & Co. KG
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- Clinical and Laboratory Evaluation of Specific Chemiluminescence Assays for Intact and Total Proinsulin
- Clinical Impact of the New Criteria for the Diagnosis of Diabetes Mellitus
- The Effect of the New ADA and WHO Guidelines on the Number of Diagnosed Cases of Diabetes Mellitus
- Detecting Type 2 Diabetes by a Single Post-Challenge Blood Sample
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- Meetings and Awards
Articles in the same Issue
- Editors' Introduction: Welcome to the Special Issue on Diabetes Mellitus
- Linking Research and Innovative Clinical Practice: The Story of Diabetes Mellitus
- Insulin Resistant States and Insulin Signaling
- Diabesity: An Inflammatory Metabolic Condition
- Plasma Adiponectin and Hyperglycaemia in Diabetic Patients
- Platelet Function and Acetyl-Coenzyme A Metabolism in Type 1 Diabetes Mellitus
- Oxidative Stress in Diabetes
- Carbonyl Stress and Diabetic Complications
- Chemical Modification of Proteins by Lipids in Diabetes
- Glyoxal and Methylglyoxal Levels in Diabetic Patients: Quantitative Determination by a New GC/MS Method
- Dyslipidemia in Patients with Type 2 Diabetes. Relationships between Lipids, Kidney Disease and Cardiovascular Disease
- Haemoglobin A1c – A Marker for Complications of Type 2 Diabetes: The Experience from the UK Prospective Diabetes Study (UKPDS)
- Glycated Hemoglobin Standardization – National Glycohemoglobin Standardization Program (NGSP) Perspective
- Haemoglobin A1c: Analysis and Standardisation
- Point-of-Care Testing in Diabetes Mellitus
- Evaluation of Portable Blood Glucose Meters. Problems and Recommendations
- Measurements of Glucose on the Skin Surface, in Stratum Corneum and in Transcutaneous Extracts: Implications for Physiological Sampling
- Biological Variability of Albumin Excretion Rate and Albumin-to-Creatinine Ratio in Hypertensive Type 2 Diabetic Patients
- Clinical and Laboratory Evaluation of Specific Chemiluminescence Assays for Intact and Total Proinsulin
- Clinical Impact of the New Criteria for the Diagnosis of Diabetes Mellitus
- The Effect of the New ADA and WHO Guidelines on the Number of Diagnosed Cases of Diabetes Mellitus
- Detecting Type 2 Diabetes by a Single Post-Challenge Blood Sample
- Laboratory Tests in Diagnosis and Management of Diabetes Mellitus. Practical Considerations
- Obesity, Glucose Intolerance and Diabetes and Their Links to Cardiovascular Disease. Implications for Laboratory Medicine
- Meetings and Awards