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Hamostaseologie Dec 2022Blood coagulation analysis is characterized by the application of a variety of materials, reagents, and analyzers for the determination of the same parameter, or... (Review)
Review
Blood coagulation analysis is characterized by the application of a variety of materials, reagents, and analyzers for the determination of the same parameter, or analyte, by different laboratories worldwide. Accordingly, the application of common reference intervals, that, by definition, would represent a "range of values (of a certain analyte) that is deemed normal for a physiological measurement in healthy persons," is difficult to implement without harmonization of procedures. In fact, assay-specific reference intervals are usually established to allow for the discrimination of normal and abnormal values during evaluation of patient results. While such assay-specific reference intervals are often determined by assay manufacturers and subsequently adopted by customer laboratories, verification of transferred values is still mandatory to confirm applicability on site. The same is true for reference intervals that have been adopted from other laboratories, published information, or determined by indirect data mining approaches. In case transferable reference intervals are not available for a specific assay, a direct recruiting approach may or needs to be applied. In comparison to transferred reference interval verification, however, the direct recruiting approach requires a significantly higher number of well-defined samples to be collected and analyzed. In the present review, we aim to give an overview on the above-mentioned aspects and procedures, also with respect to relevant standards, regulations, guidelines, but also challenges for both, assay manufacturers and coagulation laboratories.
Topics: Humans; Reference Values; Blood Coagulation; Laboratories
PubMed: 36549290
DOI: 10.1055/a-1945-9490 -
Pediatric Research Sep 2023Erythroferrone (ERFE) has been identified as a hepcidin-regulating hormone synthetized by erythroblasts correlating to the erythropoietic activity and the needs for iron...
BACKGROUND
Erythroferrone (ERFE) has been identified as a hepcidin-regulating hormone synthetized by erythroblasts correlating to the erythropoietic activity and the needs for iron substrate in bone marrow of adults. The present study aimed to assess the ERFE serum concentrations and its predictors in infants.
METHODS
ERFE was explored at 4 time points during the first year of life in 45 healthy, breastfed, normal birth weight (NBW) infants, and 136 marginally low birth weight infants (LBW, 2000-2500 g) receiving iron (N = 58) or placebo (N = 78) between 6 weeks and 6 months of age.
RESULTS
ERFE concentrations were low at birth, increasing gradually during the first year of life. In NBW infants, reference ranges (5th to 95th percentile) were at 6 weeks <0.005-0.99 ng/mL and at 12 months <0.005-33.7 ng/mL. ERFE was higher in LBW infants at 6 weeks but lower at 12 months compared to NBW and minimally affected by iron supplementation among LBW infants. Correlations of ERFE with erythropoietic and iron status markers were weak and inconsistent.
CONCLUSIONS
The role of ERFE in the crosstalk of erythropoiesis and iron homeostasis remains unclear in infants and further studies on ERFE in infants and older children are warranted within the framework of the erythropoietin-ERFE-hepcidin axis.
IMPACT
Normal range of erythroferrone in healthy infants is described for the first time. Erythroferrone in infants lacks correlation to iron status and markers of erythropoiesis. The findings indicate differences in infant regulation of iron homeostasis as compared to adults. The findings point to a need to study infant erythropoiesis separately from its adult counterpart. The findings may have clinical impact on management strategies of iron-loading anemia in infancy.
Topics: Adolescent; Adult; Child; Humans; Infant; Infant, Newborn; Erythropoiesis; Hepcidins; Iron; Reference Values; Peptide Hormones
PubMed: 37069224
DOI: 10.1038/s41390-023-02594-2 -
Deutsches Arzteblatt International Jun 2017The prevalence of latent/subclinical hypothyroidism is between 3% and 10%, according to epidemiologic studies that have been carried out in the USA, the United Kingdom,... (Review)
Review
BACKGROUND
The prevalence of latent/subclinical hypothyroidism is between 3% and 10%, according to epidemiologic studies that have been carried out in the USA, the United Kingdom, and Denmark. As persons with latent hypo - thyroidism are often asymptomatic, the diagnosis is often made incidentally in routine laboratory testing.
METHODS
This review is based on a selective search in PubMed for publications on the diagnosis and treatment of latent hypothyroidism. All pertinent articles and guidelines published from 1 January 2000 to 31 July 2016 were included.
RESULTS
The diagnosis of latent hypothyroidism is generally assigned after repeated measurement of a TSH concentration above 4.0 mU/L in a person whose fT4 concentration is in the normal range. The most common cause is autoimmune thyroiditis, which can be detected by a test for autoantibodies. L-thyroxin supplementation is a controversial matter: its purpose is to prevent the development of overt hypothyroidism, but there is a danger of overtreatment, which increases the risk of fracture. To date, no benefit of L-thyroxin supplementation has been demonstrated with respect to morbidity and mortality, health-related quality of life, mental health, cognitive function, or reduction of overweight. There is, however, evidence of a beneficial effect on cardiac function in women, and on the vascular system. At present, treatment is generally considered indicated only if the TSH level exceeds 10.0 mU/L.
CONCLUSION
Limited data are available on the relevant clinical endpoints and undesired side effects of supplementation therapy. Physicians should advise patients about the indications for such treatment on an individual basis after due consideration of the risks and benefits.
Topics: Adult; Female; Humans; Hypothyroidism; Pregnancy; Prevalence; Quality of Life; Reference Values; Thyrotropin; Young Adult
PubMed: 28683860
DOI: 10.3238/arztebl.2017.430 -
The Journal of Allergy and Clinical... Oct 2023Physiological levels of basal serum tryptase vary among healthy individuals, depending on the numbers of mast cells, basal secretion rate, copy numbers of the TPSAB1... (Review)
Review
Physiological levels of basal serum tryptase vary among healthy individuals, depending on the numbers of mast cells, basal secretion rate, copy numbers of the TPSAB1 gene encoding alpha tryptase, and renal function. Recently, there has been a growing debate about the normal range of tryptase because individuals with the hereditary alpha tryptasemia (HαT) trait may or may not be symptomatic, and if symptomatic, uncertainty exists as to whether this trait directly causes clinical phenotypes or aggravates certain conditions. In fact, most HαT-positive cases are regarded as asymptomatic concerning mast cell activation. To address this point, experts of the European Competence Network on Mastocytosis (ECNM) and the American Initiative in Mast Cell Diseases met at the 2022 Annual ECNM meeting and discussed the physiological tryptase range. Based on this discussion, our faculty concluded that the normal serum tryptase range should be defined in asymptomatic controls, inclusive of individuals with HαT, and based on 2 SDs covering the 95% confidence interval. By applying this definition in a literature screen, the normal basal tryptase in asymptomatic controls (HαT-positive persons included) ranges between 1 and 15 ng/mL. This definition should avoid overinterpretation, unnecessary referrals, and unnecessary anxiety or anticipatory fear of illness in healthy individuals.
Topics: Humans; Tryptases; Reference Values; Mast Cells; Mastocytosis
PubMed: 37572755
DOI: 10.1016/j.jaip.2023.08.008 -
The Journal of Hand Surgery, European... Dec 2022
Topics: Humans; Reference Values
PubMed: 36324237
DOI: 10.1177/17531934221132666 -
Iranian Journal of Kidney Diseases May 2012Glomerular filtration rate is low in fetal and neonatal life. It increases after birth and reaches approximately 20 mL/min/1.73 m2 at 1 month of age in term and preterm... (Review)
Review
Glomerular filtration rate is low in fetal and neonatal life. It increases after birth and reaches approximately 20 mL/min/1.73 m2 at 1 month of age in term and preterm neonates. Various methods have been used to measure glomerular filtration rate in neonates such as inulin clearance, creatinine clearance, and serum cystatin C. Serum creatinine concentrations are influenced by many factors. It is suggested to use other markers which are stable over time and are not affected by muscle mass or tubular reabsorption and secretion. Cystatin C incorporates these characteristics; however, there are some other limitations in the use of cystatin C as a marker of kidney function in neonates. Additionally, the numbers of studies focused on the use of cystatin C in neonates is limited. There is a need for further studies to determine cystatin C's normal range levels and investigate whether cystatin C can replace other tests such as serum creatinine as marker of kidney function in newborn babies. Assessment of newer kidney function tests is also warranted in newborn infants.
Topics: Biomarkers; Creatinine; Cystatin C; Gestational Age; Glomerular Filtration Rate; Humans; Infant, Newborn; Infant, Premature; Inulin; Kidney Function Tests; Reference Values; Renal Agents
PubMed: 22555478
DOI: No ID Found -
American Journal of Physiology. Renal... Jul 2020Albuminuria in the pathological range is a significant predictor of preeclampsia. In healthy persons, high normal urinary albumin predicts a later incidence of...
Albuminuria in the pathological range is a significant predictor of preeclampsia. In healthy persons, high normal urinary albumin predicts a later incidence of hypertension and is associated with salt sensitivity of blood pressure. We hypothesized that in pregnancy urinary albumin in the normal range associates with blood pressure through activation of distal Na reabsorption and renal salt retention by plasma factors cofiltered with albumin. We analyzed 24-h urine collections and plasma samples from of 560 pregnant women from the Odense Child Cohort, a Danish population-based cohort. Plasma and urinary aldosterone were measured by ELISA. Plasma and urinary Na, K, Cl, and creatinine were also determined. Predictive values of urinary albumin were assessed by linear mixed, multiple, and Cox regression analyses. Primary outcomes were blood pressure and renal electrolyte handling. Twenty-four-hour urinary albumin excretion at associated with gestational blood pressure trajectory, with adjusted β coefficients (95% confidence intervals) for each 10-fold increase in urinary albumin as follows: 5.71 (1.60 to 9.81) mmHg for systolic blood pressure and 4.39 (1.41 to 7.38) mmHg for diastolic blood pressure. Urinary albumin was inversely associated with fractional excretion rates of Na, K, and Cl, with adjusted β coefficients (95% confidence intervals) for each 10-fold increase in urine albumin as follows: -0.25 (-0.35 to -0.14), -5.06 (-6.81 to -3.30), and -0.28 (-0.41 to -0.15), respectively. In conclusion, at , urinary albumin excretion in the normal range associated with blood pressure and renal electrolyte handling independent of potential confounders.
Topics: Adult; Albuminuria; Blood Pressure; Female; Humans; Kidney; Pregnancy; Reference Values; Young Adult
PubMed: 32463729
DOI: 10.1152/ajprenal.00044.2020 -
The Journal of Allergy and Clinical... Nov 2022During the first year of life, B-cell level is a valuable indicator of whether external factors, such as exposure to B-cell-depleting therapies, have an adverse impact... (Meta-Analysis)
Meta-Analysis
BACKGROUND
During the first year of life, B-cell level is a valuable indicator of whether external factors, such as exposure to B-cell-depleting therapies, have an adverse impact on immune system development. However, there are no standard reference ranges of B-cell levels in healthy infants by age.
OBJECTIVE
Our aim was to estimate the normal range of B-cell levels in infants, by age, during the first year of life by pooling data from published studies.
METHODS
Studies reporting B-cell levels measured by using flow cytometry and CD19 markers in healthy infants were identified via a systematic literature review. Quality and feasibility assessments determined suitability for inclusion in meta-analyses by age group and/or continuous age. Means and normal ranges (2.5th-97.5th percentile) were estimated for absolute and percentage B-cell levels. Sensitivity analyses assessed the impact of various assumptions.
RESULTS
Of the 37 relevant studies identified, 28 were included in at least 1 meta-analysis. The means and normal ranges of B-cell levels were found to be 707 cells/μL in cord blood (range 123-2324 cells/μL), 508 cells/μL in infants aged 0 to 1 month (range 132-1369 cells/μL), 1493 cells/μL in infants aged 1 to 6 months (range 416-3877 cells/μL), and 1474 cells/μL in infants older than 6 months (range 416-3805 cells/μL). The continuous age model showed that B-cell levels peaked at week 26. Trends were similar for the percentage B-cell estimates and in sensitivity analyses.
CONCLUSION
These meta-analyses provide the first normal reference ranges for B-cell levels in infants, by week of age, during the first year of life.
Topics: Infant; Humans; Reference Values; Flow Cytometry; B-Lymphocytes; Antigens, CD19
PubMed: 35728653
DOI: 10.1016/j.jaci.2022.06.006 -
BMC Endocrine Disorders Feb 2021Hemoglobin A1c (HbA1c) is the product of a non-enzymatic chemical reaction between hemoglobin (Hb) and glucose. However, the association between Hb and HbA1c remains to...
BACKGROUND
Hemoglobin A1c (HbA1c) is the product of a non-enzymatic chemical reaction between hemoglobin (Hb) and glucose. However, the association between Hb and HbA1c remains to be fully elucidated in view of the controversial findings reported to date. Therefore, our aim in this study was to evaluate the association between Hb levels within the normal range and HbA1c levels among Chinese non-diabetes adults using cross-sectional data from the China Health and Nutrition Survey 2009.
METHODS
Our analysis was based on the data of 1659 non-diabete adults 20-49 years of age. Multivariable linear models were applied to examine the association between Hb and HbA1c levels. Subgroup analyses stratified by age and sex were also performed.
RESULTS
The association between Hb and HbA1c levels was positive in the unadjusted model (β =0.020, 95% CI: 0.008, 0.032). However, this association did not remain significant when the regression model was minimally adjusted for age and sex (β =0.006, 95% CI: - 0.014, 0.024); this association became negative when the model was further adjusted for covariates whose effect estimates of HbA1c levels more than 10% (β = - 0.042, 95% CI: - 0.064, - 0.020). The association remained negative on subgroup analyses stratified by age (20-34 years: β = - 0.052, 95% CI: - 0.091, - 0.013; 35-49 years: β = - 0.041, 95% CI: - 0.068, - 0.014) and sex (men: β = - 0.042, 95% CI: - 0.074, - 0.010; women: β = - 0.042, 95% CI: - 0.073, - 0.012) when controlling for covariates.
CONCLUSIONS
Our findings revealed that Hb levels within the normal range were negatively associated with HbA1c levels among Chinese non-diabetes adults. Confounding factors, such as red blood cell counts can affect the association between Hb and HbA1c levels.
Topics: Adult; Asian People; Blood Glucose; Cross-Sectional Studies; Female; Glycated Hemoglobin; Hemoglobins; Humans; Male; Middle Aged; Population Surveillance; Reference Values; Surveys and Questionnaires; Young Adult
PubMed: 33639896
DOI: 10.1186/s12902-021-00704-x -
The Neuroradiology Journal Aug 2021An abnormally decreased clivoaxial angle (CXA) is used during the clinical evaluation for corrective skull base surgery. Published normal ranges of CXA using x-ray,...
OBJECTIVE
An abnormally decreased clivoaxial angle (CXA) is used during the clinical evaluation for corrective skull base surgery. Published normal ranges of CXA using x-ray, computed tomography, or magnetic resonance imaging (MRI) vary dramatically, especially with neck flexion or extension. The aim of this study was to use high-resolution MRI to determine the normal range of CXA in various neck positions using a reproducible measurement technique.
METHODS
The CXA was measured in 10 healthy volunteers on sagittal T2 SPACE c-spine MRI in supine and prone positions and with the neck both neck and extended. CXA is strictly defined as the angle between a line along the inferior third of the dorsal clival cortex and a line from the superior/posterior cortex of the dens to the posterior/inferior corner of the C2 body. Statistical analysis was performed in all positions and included mean CXA, range, standard deviation (), inter-reader agreement, and group comparisons.
RESULTS
The mean CXA overall was 156.92° (=4.23°; range 134-179°). The mean value for extension CXA was 169.20° (=5.81°), and the mean value for flexion CXA was 144.73° (=5.71°), the difference being statistically significant (<0.0001) regardless of supine or prone position. Concordant correlations of reader measurements showed substantial agreement in the supine position at 0.96, with lower agreement in the prone position at 0.87.
CONCLUSIONS
We report normal ranges for CXA in various neck positions based on 3D T2-weighted MRI, using a reproducible measurement method. There was a significant difference in the CXA values between neck extended and neck flexed positions but not between supine and prone positions.
Topics: Adult; Cervical Vertebrae; Humans; Magnetic Resonance Imaging; Neck; Range of Motion, Articular; Reference Values; Tomography, X-Ray Computed
PubMed: 33678065
DOI: 10.1177/1971400921998982