Breed‐specific reference ranges for standard echocardiographic measurements in salukis

Ethnic differences in the level of thyroid hormones exist among individuals. The American Thyroid Association (ATA) recommends that an institution or region should establish a specific thyroid hormone reference value for each stage of pregnancy. To date, a limited number of studies have reported the level of thyroid hormones in Chinese minorities, and the exact relationship between BMI and thyroid function in pregnant women is ill. This study was performed to establish trimester-specific reference ranges of thyroid hormones in Zhuang ethnic pregnant women and explore the role of body mass index (BMI) on thyroid function. A total of 3324 Zhuang ethnic health pregnant women were recruited in this Zhuang population-based retrospective cross-sectional study. The values of thyroid stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were determined by automatic chemiluminescence immunoassay analyzer. Multivariate linear regression and binary logistic regression were constructed to evaluate the influence of BMI on the thyroid function. The established reference intervals for the serum thyroid hormones in three trimesters were as follows: TSH, 0.02–3.28, 0.03–3.22, and 0.08-3.71 mIU/L; FT4, 10.57–19.76, 10.05–19.23, and 8.96–17.75 pmol/L; FT3, 3.51–5.64, 3.42–5.42, and 2.93–5.03 pmol/L. These values were markedly lower than those provided by the manufacturers for nonpregnant adults which can potentially result in 6.10% to 19.73% misclassification in Zhuang pregnant women. Moreover, BMI was positively correlated with isolated hypothyroxinemia (OR=1.081, 95% CI=1.007–1.161), while the correlation between the BMI and subclinical hypothyroidism was not statistically significant (OR=0.991, 95% CI=0.917–1.072). This is the first study focusing on the reference ranges of thyroid hormones in Guangxi Zhuang ethnic pregnant women, which will improve the care of them in the diagnosis and treatment. We also found that high BMI was positively associated with the risk of isolated hypothyroxinemia.

Download Full-text

Results of an international round robin for serum and whole-blood folate

Clinical Chemistry ◽

10.1093/clinchem/42.10.1689 ◽

1996 ◽

Vol 42 (10) ◽

pp. 1689-1694 ◽

Cited By ~ 117

Author(s):

E W Gunter ◽

B A Bowman ◽

S P Caudill ◽

D B Twite ◽

M J Adams ◽

...

Keyword(s):

Public Health ◽

Clinical Data ◽

Reference Materials ◽

Whole Blood ◽

Interlaboratory Comparison ◽

Round Robin ◽

Specific Reference ◽

Reference Ranges ◽

Comparison Study ◽

International Round

Abstract Because of the increasing significance of folate nutriture to public health, a "round robin" interlaboratory comparison study was conducted to assess differences among methods. Twenty research laboratories participated in a 3-day analysis of six serum and six whole-blood pools. Overall means, SDs, and CVs derived from these results were compared within and across method types. Results reported for serum and whole-blood folate demonstrated overall CVs of 27.6% and 35.7%, respectively, across pools and two- to ninefold differences in concentrations between methods, with the greatest variation occurring at critical low folate concentrations. Although results for serum pools were less variable than those for whole-blood pools, substantial intermethod variation still occurred. The overall results underscore the urgent need for developing and validating reference methods for serum and whole-blood folate and for properly characterized reference materials. For evaluating study or clinical data, method-specific reference ranges (established with clinical confirmation of values for truly folate-deficient individuals) must be used.

Download Full-text

Are age-specific reference ranges for CYFRA 21-1 appropriate?

Scandinavian Journal of Clinical and Laboratory Investigation ◽

10.1080/00365513.2018.1449243 ◽

2018 ◽

Vol 78 (4) ◽

pp. 335-336

Author(s):

Gustav Mikkelsen ◽

Arne Åsberg ◽

Gunhild Garmo Hov

Keyword(s):

Specific Reference ◽

Reference Ranges

Download Full-text

Abstract 1601: Comprehensive Evaluation of the Left Ventricular Systolic and Diastolic Synchronicity in 160 “Completely” Healthy Normal Volunteers Using Tissue Doppler Echocardiography

Circulation ◽

10.1161/circ.116.suppl_16.ii_334-b ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Hyung-Kwan Kim ◽

Keun-Ho Park ◽

Suna-A Chang ◽

Jin-Shik Park ◽

Hyun-Jae Kang ◽

...

Keyword(s):

Age Groups ◽

Mitral Annulus ◽

Tissue Doppler ◽

Left Ventricular ◽

Doppler Imaging ◽

Cardiac Resynchronization ◽

Specific Reference ◽

Reference Ranges ◽

Normal Ranges ◽

Mitral Annulus Velocity

Background Growing use of the left ventricular(LV) systolic(LVSIsys) and diastolic synchronicity indexes(LVSIdia) in selecting potential responders to cardiac resynchronization therapy(CRT) has created a need for normative reference values. This study was performed to determine reference ranges for tissue Doppler imaging-derived LVSIsys and LVSIdia, and to assess their relationships to age and conventional parameters reflecting LV systolic and diastolic functions. Methods and Results We recruited 160 completely healthy volunteers (45±13yrs, 104 men) free of any systemic or cardiovascular disease. Maximal difference and SD of time to peak systolic and early diastolic velocities for LVSIsys and LVSIdia were measured using 6- and 12-segment models. Table and Figure represent normal ranges. Aging was not found to significantly change LVSIsys, whereas LVSIdia progressively and consistently increased with age. Significant correlations were observed between LVSIdia and parameters representing LV diastolic function, i.e. early mitral inflow velocity and its deceleration time, and early mitral annulus velocity. A physiologic rise in LV mass/Ht 2.7 showed a weak, but significant correlation with LVSIdia( r = 0.15 to 0.22), but not with LVSIsys. On multivariate analysis, age-dependent increase in LVSIdia was confirmed. Conclusions Age-specific reference ranges for LVSIsys and LVSIdia are presented here. LVSIsys remain stable throughout age groups, whereas LVSIdia progressively increases with age. These data given here will be useful for defining abnormal LV synchronous contraction and relaxation, and help better select patients likely to respond favorably to CRT.

Download Full-text

Trimester-specific reference ranges for thyroid function tests in South Indian women

Thyroid Research and Practice ◽

10.4103/trp.trp_52_18 ◽

2019 ◽

Vol 16 (1) ◽

pp. 51

Author(s):

MahmoodDhahir Al-Mendalawi

Keyword(s):

Thyroid Function ◽

Specific Reference ◽

Reference Ranges ◽

Thyroid Function Tests ◽

Indian Women ◽

Function Tests ◽

South Indian

Download Full-text

Study of thyroid volume by ultrasonography in clinically euthyroid patients

Journal of Institute of Medicine ◽

10.3126/jiom.v32i2.4944 ◽

1970 ◽

Vol 32 (2) ◽

pp. 36-43 ◽

Cited By ~ 1

Author(s):

P Kayastha ◽

S Paudel ◽

DM Shrestha ◽

RJ Ghimire ◽

S Pradhan

Keyword(s):

Surface Area ◽

Body Surface Area ◽

Reference Values ◽

Body Surface ◽

Pearson Correlation ◽

Thyroid Volume ◽

Specific Reference ◽

Reference Ranges ◽

Hilly Region ◽

Significant Difference

Introduction: The purpose of this study was to establish reference ranges of total thyroid volume among clinically euthyroid Nepalese population using Ultrasonography and correlate this volume with age, sex, individual’s built and geographic location. Methods: This was a prospective cross sectional study involving 485 clinically euthyroid individuals. B - mode Ultrasonography was used to measure the total thyroid volume by combining the volume of both the lobes obtained by using formula for prolate ellipsoid. Age specific reference values for thyroid volume were obtained and Pearson correlation test was used to see the relationship with various factors. Results: Among 485 individuals between 1 to 83 years of age, 221(45.57%) were males and 264(54.43%) were females. Maximum [354 individuals (72.99%)] were from hilly region and minimum [16 individual (3.30%)] were from Himalayan region. Mean thyroid volume was 6.629 ± 2.5025 ml. In general, thyroid volume was found to be more in older individuals than in young age group. There was no significant difference of thyroid volume between males and females. Thyroid volume best correlated with body surface area (r=0.444, p<0.0001). The volume had a positive correlation with weight (r=0.443, p<0.0001), body mass index (r=0.371, p<0.0001) and height (r=0.320, p<0.0001) of the individual. Conclusions: This study estimated the reference range of total thyroid volume for Nepalese population. These ranges are significantly lower than the WHO/ICCIDD thyroid volume references and reference values obtained in various other countries. Total thyroid volume best correlated with Body surface area. Keywords: Body surface area; clinically euthyroid; total thyroid volume; ultrasonography DOI: http://dx.doi.org/10.3126/joim.v32i2.4944 Journal of Institute of Medicine, August, 2010; 32: 36-43

Download Full-text

Direct determination of selenium in serum by graphite-furnace atomic absorption spectrometry with deuterium background correction and a reduced palladium modifier: age-specific reference ranges.

Clinical Chemistry ◽

10.1093/clinchem/34.4.709 ◽

1988 ◽

Vol 34 (4) ◽

pp. 709-714 ◽

Cited By ~ 93

Author(s):

B E Jacobson ◽

G Lockitch

Keyword(s):

Atomic Absorption ◽

Direct Method ◽

Graphite Furnace ◽

Direct Determination ◽

Background Correction ◽

Specific Reference ◽

Reference Ranges ◽

Term Infants ◽

Graphite Furnace Atomic Absorption

Abstract We describe the development of a direct method for determination of selenium in serum by graphite-furnace atomic absorption spectrophotometry with deuterium background correction. We include palladium modifier to stabilize selenium in the presence of a strong reducing agent. Spectral interferences from iron are not evident in this system. Because an analysis requires only 20 microL of serum or plasma, the method is applicable to neonatal populations. At a selenium concentration of 0.75 mumol/L (approximately the mean found in our pre-term infants), the within-run CV is 5.3%. For a concentration of 1.83 mumol/L, which approximates our normal adult mean, within-run and between-run CVs are 2.7% and 3.4%. Accuracy is demonstrated by analytical recoveries ranging from 96% to 102%. We present reference values for pre-term and term infants, and age-specific ranges for infants to adults.

Download Full-text

Age- and sex-specific pediatric reference intervals for biochemistry analytes as measured with the Ektachem-700 analyzer.

Clinical Chemistry ◽

10.1093/clinchem/34.8.1622 ◽

1988 ◽

Vol 34 (8) ◽

pp. 1622-1625 ◽

Cited By ~ 76

Author(s):

G Lockitch ◽

A C Halstead ◽

S Albersheim ◽

C MacCallum ◽

G Quigley

Keyword(s):

Calcium Phosphate ◽

Total Protein ◽

Reference Intervals ◽

Specific Reference ◽

Healthy Population ◽

Reference Ranges ◽

Older Children ◽

Related Difference ◽

Film Analyzer ◽

Age And Sex

Abstract Using the Ektachem-700 multilayer film analyzer, we defined age- and sex-specific reference intervals for 20 analytes in sera from a healthy population of neonates and children ages one to 19 years. Upper and lower normal reference intervals for each analyte were determined by nonparametric methods as the 0.975 and 0.025 fractiles, respectively. Newborns have lower concentrations of total protein and albumin, and higher concentrations of phosphate, bilirubin, and enzymes in serum than older children do. Concentrations of urea, glucose, calcium, phosphate, and bilirubin change rapidly postnatally. Outside the neonatal period, no significant age- or sex-related difference was found for plasma glucose, serum amylase, conjugated or unconjugated bilirubin, or lipase. There was no sex-related difference in reference intervals for albumin, total protein, calcium, phosphate, or urea. However, concentrations of uric acid and creatine kinase are much higher in postpubertal boys than in girls. Alkaline phosphatase values peak later in boys. Except for lactate dehydrogenase and gamma-glutamyltransferase, the reference intervals defined here do not differ strikingly from data derived with use of other analyzers. The age- and sex-related trends are independent of method. However, each laboratory should determine the degree to which these reference ranges can be directly applied to analyses performed with another analyzer.

Download Full-text

Ramifications of variability in sex hormone-binding globulin measurement by different immunoassays on the calculation of free testosterone

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/0004563219888549 ◽

2019 ◽

Vol 57 (1) ◽

pp. 88-94

Author(s):

Joanne Adaway ◽

Brian Keevil ◽

Annmarie Miller ◽

Phillip J Monaghan ◽

Nicola Merrett ◽

...

Keyword(s):

Free Testosterone ◽

Sex Hormone ◽

Sex Hormone Binding Globulin ◽

Specific Reference ◽

Reference Ranges ◽

Hormone Binding ◽

Serum Samples ◽

Appropriate Treatment ◽

Result Interpretation ◽

Abbott Architect

Objective Sex hormone-binding globulin (SHBG) is a glycoprotein which binds hormones such as testosterone. Around 97% of circulating testosterone is bound to SHBG or albumin and is therefore biologically unavailable; 2–3% of testosterone is free. Free testosterone is very technically challenging to quantify; in order to circumvent this problem, equations using testosterone and SHBG are used to estimate free testosterone. We decided to determine the effect of using different SHBG immunoassays on calculated free testosterone results. Design Anonymized surplus serum samples were analysed for SHBG on four different immunoassay platforms (Abbott Architect, Roche, Beckman and Siemens). The SHBG results were used to generate a Vermeulen calculated free testosterone. Results Beckman Access and Siemens Centaur both gave results close to the overall mean. Roche gave the highest SHBG concentrations with Abbott Architect producing the lowest results. Abbott Architect gave the highest calculated free testosterone results, followed by Beckman. Roche gave the lowest results. Sixty-five per cent of male samples had low calculated free testosterone and 27.5% of the females had high calculated free testosterone using the SHBG from the Abbott assay compared with 69% low male calculated free testosterone and 20% high female calculated free testosterone with the Roche assay. Conclusion Our results have shown significant differences in SHBG results produced by different analysers and subsequently the calculated free testosterone, which may affect result interpretation if method-specific reference ranges for calculated free testosterone are not used. Care should be taken to ensure reference ranges are appropriate for the analyser used to avoid misdiagnosis of hypo or hyperandrogenism, and ensure patients get the most appropriate treatment.

Download Full-text