Provisional Kuwaiti Children Hematology Reference Range

SummaryAge-related trends in serum free thyroxine (FT4) and free triiodothyronine (FT3) concentrations were measured in 7248 euthyroid subjects (age-range 3 months to 106 years). 5700 were patients referred to hospitals for investigation of suspected thyroid dysfunction, but who were diagnosed euthyroid. 1548 were healthy blood donors (age-range 18-63 years) with no indication of thyroid dysfunction. FT4 concentrations were little affected by the age, the sex or the state of health of the subjects in either group. Serum FT3 concentrations were significantly affected by both age and health factors. The upper limit of the euthyroid reference range for young subjects up to 15 years was about 20% higher (10.4 pmol/1) than for adult subjects older than 25 years (8.8 pmol/1). The change in the upper limits typical of young subjects to that typical of adults occurred steadily over the decade 15–25 years. After this age, little further change occurred, especially in healthy subjects. Additionally, the lower limit of the euthyroid range for FT3 was extended by the inclusion in the reference group of patients referred to hospitals. Compared with the lower limit of the FT3 range for healthy subjects (5 pmol/1), the corresponding limit for referred subjects (young or adult) was 3.5–3.8 pmol/1. Broadening of the FT3 reference range was probably brought about by a significant number of patients in the hospital-referred group with the “1OW-T3 syndrome” of mild non-thyroidal illness. Accordingly, FT3 was inferior to FT4 in the discrimination of hypothyroidism, as FT4 was unaffected by this phenomenon. Effects of age and non-thyroidal illness on serum FT3 concentrations require great care when selecting subjects for a laboratory euthyroid reference range typical of the routine workload. Constraints on the choice of subjects for FT4 reference ranges are less stringent.

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Evaluation of normal reference range for thyroid uptake of technetium-99 m in a single centre UK population

Endocrine Abstracts ◽

10.1530/endoabs.50.p402 ◽

2017 ◽

Author(s):

Mavin Macauley ◽

Mohamed Shagwi ◽

Kim Howe ◽

Andrew Curry ◽

Elizabeth Howell ◽

...

Keyword(s):

Reference Range ◽

Single Centre ◽

Normal Reference Range ◽

Normal Reference ◽

Thyroid Uptake

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Low free T3 levels within the reference range independently predict cardiovascular mortality in the general population

Endocrine Abstracts ◽

10.1530/endoabs.56.oc1.5 ◽

2018 ◽

Author(s):

Joao Sergio Neves ◽

Catarina Viegas Dias ◽

Lia Leitao ◽

Miguel Bigotte Vieira ◽

Rita Magrico ◽

...

Keyword(s):

General Population ◽

Cardiovascular Mortality ◽

Reference Range ◽

Free T3

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Could Thyroid Disorders Be Better Understood and Dealt as a Thyroid Syndrome

International Journal of Innovative Research in Medical Science ◽

10.23958/ijirms/vol05-i08/900 ◽

2020 ◽

Vol 5 (08) ◽

pp. 326-328

Author(s):

Dr. Sushma Patil ◽

Dr. Vikrant Patil

Keyword(s):

Reference Range ◽

Well Being ◽

Thyroid Disorders ◽

Thyroid Function Tests ◽

Thyroid Disorder ◽

Serum Concentrations ◽

Comorbid Conditions ◽

Free T4 ◽

Research Perspective ◽

Wide Range

Thyroid disorders are common worldwide. Thyroid dysfunction, both hypo- and hyperthyroidism may increase the risk of cardiovascular disorders. Current thyroid function tests may have limitations since they only measure the total or free T4 and/or T3 and TSH serum concentrations in peripheral blood and not the effect of T4 or T3 serum on different specific target tissues. Several comorbid conditions can interfere with the absorption or increase the clearance of levothyroxine. Among patients treated with thyroid replacement, under or overmedicated may-be at risk for adverse health consequences. A wide range of drugs may interfere with levothyroxine absorption, metabolism, and action. Patients report a lack of well-being, despite reaching euthyroid reference range of TSH, with psychological distress. If we will consider Thyroid related conditions as a syndrome then research perspective at the pathophysiology, interrelation between symptoms and comorbidities will be much broader that can lead researchers to get insights of different pathways in which thyroid gland functioning can be perceived and dealt therapeutically. The deliberation of thyroid disorder as a syndrome can affluence our knowledge of correlating cofounders, action of thyroid hormones on target tissues, underlying cause and thyroid health.

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Establishment of multivariate reference range of P-wave amplitude based on depth function

Academic Journal of Second Military Medical University ◽

10.3724/sp.j.1008.2010.01215 ◽

2010 ◽

Vol 30 (11) ◽

pp. 1215-1217

Author(s):

Jiu WANG ◽

Hong-wei SUN ◽

Yong GAO ◽

Tian-he XU

Keyword(s):

Wave Amplitude ◽

Reference Range ◽

P Wave ◽

Depth Function

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New normal range of fetal cavum septum pellucidum in the second trimester of gestation

10.21516/2413-1458-2020-19-1-21-24 ◽

2020 ◽

Author(s):

M.V. Medvedev, O.I. Kozlova, À.Yu. Romanova

Keyword(s):

Brain Development ◽

Reference Range ◽

Fetal Brain ◽

Septum Pellucidum ◽

Second Trimester ◽

Normal Range ◽

Cavum Septum Pellucidum ◽

New Normal ◽

Biparietal Diameter ◽

Fetal Brain Development

Fetal brain was retrospectively evaluated in 418 normal fetuses at 16–28 weeks of gestation. The multiplanar mode to obtain the axial cerebral plane and measured the width of the cavum septum pellucidum (CSP) and biparietal diameter (BD). All measurements of CSP were done from as the widest diameter across both borders in an inter-to inter fashion. The CSP width is increasing at second trimester of gestation. Normal range plotted on the reference range (mean, 5th and 95th percentiles) of fetal width CSP by measuring of its size may be useful for assessment of fetal brain development in the second trimester of gestation.

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Computerized method for validating laboratory reference ranges for triiodothyronine and thyroxin immunoassays

Clinical Chemistry ◽

10.1093/clinchem/37.3.438 ◽

1991 ◽

Vol 37 (3) ◽

pp. 438-442 ◽

Cited By ~ 1

Author(s):

Brian Luttrell ◽

Sall Watters

Keyword(s):

Reference Range ◽

Normal Values ◽

Reference Group ◽

Normal Population ◽

Normal Subjects ◽

Reference Ranges ◽

Large Samples ◽

Laboratory Reference ◽

Euthyroid Status ◽

Computer Based

Abstract We used a computer-based method to help validate the reference ranges of assays for triiodothyronine (T3) and thyroxin (T4). A retrospective search of a database of laboratory results for the previous six months identified all patients with apparent euthyroid status, as defined by methods independent of the immunoassay under review. A computer-generated reference group (CGR Group) of 2001 records had a gaussian distribution of T4 values and a reference range (mean +/- 2 SD) of 56-161 nmol/L, compared with the supplier's suggested range for euthyroid subjects (58-148 nmol/L) and an in-house range of 60-144 nmol/L for a group of 97 normal subjects. A similar CGR Group of 1902 records gave a reference range for T3 of 0.7-2.1 nmol/L (manufacturer's range 0.8-2.8; normal subjects 0.8-2.2). An attempt to devise a reference range for thyrotropin failed when we found that its concentration in the population of patients with normal values for thyroid hormones was distributed differently from that in the normal population. The method is intended to be used in addition to conventionally derived ranges based on results for healthy subjects. It allows the laboratory to conveniently verify the reference ranges for T3 and T4 assays at regular intervals by using very large samples with appropriate age, sex, and weight distribution, drawn from the population of patients' samples submitted for analysis.

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Association between Blood Pressure and Serum Thyroid-Stimulating Hormone Concentration within the Reference Range: A Population-Based Study

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2006-2208 ◽

2007 ◽

Vol 92 (3) ◽

pp. 841-845 ◽

Cited By ~ 119

Author(s):

Bjørn O. Åsvold ◽

Trine Bjøro ◽

Tom I. L. Nilsen ◽

Lars J. Vatten

Keyword(s):

Blood Pressure ◽

Diastolic Blood Pressure ◽

Outcome Measures ◽

Odds Ratio ◽

Reference Range ◽

Positive Association ◽

Population Based ◽

Thyroid Stimulating Hormone ◽

Cross Sectional ◽

Population Based Study

Abstract Context: The association between thyroid function and blood pressure is insufficiently studied. Objective: The objective of the investigation was to study the association between TSH within the reference range and blood pressure. Design and Setting: This was a cross-sectional, population-based study. Subjects: A total of 30,728 individuals without previously known thyroid disease were studied. Main Outcome Measures: The main outcome measures were mean systolic and diastolic blood pressure and pulse pressure and odds ratio for hypertension (>140/90 mm Hg or current or previous use of antihypertensive medication), according to categories of TSH. Results: Within the reference range of TSH (0.50–3.5 mU/liter), there was a linear increase in blood pressure with increasing TSH. The average increase in systolic blood pressure was 2.0 mm Hg [95% confidence interval (CI) 1.4–2.6 mm Hg] per milliunit per liter increase in TSH among men, and 1.8 mm Hg (95% CI 1.4–2.3 mm Hg) in women. The corresponding increase in diastolic blood pressure was 1.6 mm Hg (95% CI 1.2–2.0 mm Hg) in men and 1.1 mm Hg (95% CI 0.8–1.3 mm Hg) in women. Comparing TSH of 3.0–3.5 mU/liter (upper part of the reference) with TSH of 0.50–0.99 mU/liter (lower part of the reference), the odds ratio for hypertension was 1.98 (95% CI 1.56–2.53) in men and 1.23 (95% CI 1.04–1.46) in women. Conclusion: Within the reference range of TSH, we found a linear positive association between TSH and systolic and diastolic blood pressure that may have long-term implications for cardiovascular health.

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Direct comparison of performance characteristics of two immunoassays for bone isoform of alkaline phosphatase in serum

Clinical Chemistry ◽

10.1093/clinchem/43.11.2052 ◽

1997 ◽

Vol 43 (11) ◽

pp. 2052-2057 ◽

Cited By ~ 25

Author(s):

Christopher P Price ◽

Thomas P Milligan ◽

Claude Darte

Keyword(s):

Alkaline Phosphatase ◽

Reference Range ◽

Cross Reactivity ◽

Performance Characteristics ◽

Paget Disease ◽

Specific Assay ◽

Comparison Of Results ◽

Immunometric Assay ◽

Detailed Evaluation ◽

Electrophoretic Procedure

Abstract A clinical need exists for a sensitive and specific assay for the quantitation of the bone isoform of alkaline phosphatase in serum. The majority of methods do not meet this requirement; however, the recent development of immunoassays for this isoform may provide a solution. In a detailed evaluation of two immunoassays, we found a degree of imprecision that enables the discrimination of changes within the reference range. The cross-reactivity of the liver isoform was found to be between 7.1% and 12.7% when two different methods of assessment were used. The comparison of results with an electrophoretic procedure showed that the immunocapture method recovered less of the bone isoform in samples from children than in samples from patients with Paget disease; no such difference was found with the immunometric method. This suggests that the immunocapture antibody may discriminate between different bone isoforms in children whereas the immunometric assay does not.

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