Continuous Age-Dependent Reference Ranges for Thyroid Hormones in Neonates, Infants, Children and Adolescents Established Using the ADVIA(r) Centaur(tm) Analyzer
-
Ulrich Hübner
Abstract
In neonates, infants, children and adolescents serum concentrations of the thyroid hormones show a clear age dependency. Currently, age-dependent thyroid hormone reference ranges for the new ADVIA® Centaur™ immunoanalyzer are not available. Thyroid-stimulating hormone (TSH), free thyroxine (FT4), total thyroxine (T4), free triiodothyronine (FT3) and total triiodothyronine (T3) were determined in the sera of 460 healthy children aged 0 days to 18 years from an inland (n=308) and a seaside city (n=152) using the Bayer ADVIA® Centaur™ analyzer. Square root functions defining the upper and lower limit of the continuous age-dependent reference range and the median line for each thyroid hormone were estimated applying a parametric regression technique. Continuous age-dependent reference ranges show a better fit to the obtained data than discontinuous reference ranges. The median TSH and FT4 concentrations decrease within the first year of life and are nearly constant until 18 years of age. The median T4 decreases within the entire age interval, whereas the median FT3 is constant. The median T3 increases within the first year of life and decreases afterwards. The calculated continuous reference ranges for T4, T3 and partly FT4 are consistent with published reference ranges. However, the reference ranges obtained for FT3 and partly TSH differed considerably, compared to published reference ranges. No significant residence- or sex-specific effects on age-adjusted hormone concentrations were found except for a slight residence-specific effect on age-adjusted FT4, which was probably due to assay imprecision. Due to the lack of international standardization, the assay-specific evaluation of reference ranges is very important. Continuous age-dependent reference ranges comply better with the biological reality and are more reliable than discontinuous reference ranges.
Copyright (c) 2002 by Walter de Gruyter GmbH & Co. KG
Articles in the same Issue
- The 9th Asian Pacific Congress of Clinical Biochemistry
- Circulating DNA in Plasma and Serum: Biology, Preanalytical Issues and Diagnostic Applications
- Role of Steroid Hormones and Growth Factors in Breast Cancer
- Gene Polymorphism and Coronary Risk Factors in Indian Population
- Clinical Utility of Free Drug Monitoring
- Telomerase – a Potential Molecular Marker of Lung and Cervical Cancer
- Association of Polymorphisms in the Collagen Region of Human SP-A1 and SP-A2 Genes with Pulmonary Tuberculosis in Indian Population
- Effect of Hemodialysis on the Oxidative Stress and Antioxidants
- Total Iron Binding Capacity and Transferrin Concentration in the Assessment of Iron Status
- Increased Levels of Osteoprotegerin in Hemodialysis Patients
- Levels of Testosterone, Allopregnanolone and Homocysteine in Severe Hypothyroidism
- The Levels of Serum Vitamin C, Malonyldialdehyde and Erythrocyte Reduced Glutathione in Chronic Obstructive Pulmonary Disease and in Healthy Smokers
- Highly Specific, Simple and Rapid Method for the Determination of Malondialdehyde in Blood Using High-Performance Liquid Chromatography
- Precision and Accuracy of a HPLC Method for Measurement of Fecal Porphyrin Concentrations
- Continuous Age-Dependent Reference Ranges for Thyroid Hormones in Neonates, Infants, Children and Adolescents Established Using the ADVIA(r) Centaur(tm) Analyzer
- Diagnostic Value of Various Urine Tests in the Jordanian Population with Urinary Tract Infection
- Performance Evaluation of the Precision™ PCx™ Point-of-Care Blood Glucose Analyzer Using Discriminant Ratio Methodology
- Clinical Evaluation of a New Automated Anti-dsDNA Fluorescent Immunoassay
- Upper Reference Limits for Urinary Catecholamines, Metanephrines and 3-Methoxy-4-Hydroxymandelic Acid in Hypertensive Patients
- Growth Hormone Immunoassays: Proposal to Reduce Interlaboratory Variability
- Poetry, Images and Visions: William Blake
- Meetings and Awards
Articles in the same Issue
- The 9th Asian Pacific Congress of Clinical Biochemistry
- Circulating DNA in Plasma and Serum: Biology, Preanalytical Issues and Diagnostic Applications
- Role of Steroid Hormones and Growth Factors in Breast Cancer
- Gene Polymorphism and Coronary Risk Factors in Indian Population
- Clinical Utility of Free Drug Monitoring
- Telomerase – a Potential Molecular Marker of Lung and Cervical Cancer
- Association of Polymorphisms in the Collagen Region of Human SP-A1 and SP-A2 Genes with Pulmonary Tuberculosis in Indian Population
- Effect of Hemodialysis on the Oxidative Stress and Antioxidants
- Total Iron Binding Capacity and Transferrin Concentration in the Assessment of Iron Status
- Increased Levels of Osteoprotegerin in Hemodialysis Patients
- Levels of Testosterone, Allopregnanolone and Homocysteine in Severe Hypothyroidism
- The Levels of Serum Vitamin C, Malonyldialdehyde and Erythrocyte Reduced Glutathione in Chronic Obstructive Pulmonary Disease and in Healthy Smokers
- Highly Specific, Simple and Rapid Method for the Determination of Malondialdehyde in Blood Using High-Performance Liquid Chromatography
- Precision and Accuracy of a HPLC Method for Measurement of Fecal Porphyrin Concentrations
- Continuous Age-Dependent Reference Ranges for Thyroid Hormones in Neonates, Infants, Children and Adolescents Established Using the ADVIA(r) Centaur(tm) Analyzer
- Diagnostic Value of Various Urine Tests in the Jordanian Population with Urinary Tract Infection
- Performance Evaluation of the Precision™ PCx™ Point-of-Care Blood Glucose Analyzer Using Discriminant Ratio Methodology
- Clinical Evaluation of a New Automated Anti-dsDNA Fluorescent Immunoassay
- Upper Reference Limits for Urinary Catecholamines, Metanephrines and 3-Methoxy-4-Hydroxymandelic Acid in Hypertensive Patients
- Growth Hormone Immunoassays: Proposal to Reduce Interlaboratory Variability
- Poetry, Images and Visions: William Blake
- Meetings and Awards
