Gender-specific reference intervals for serum prolactin concentrations before and after precipitation by polyethylene glycol

Prolactin, a hormone secreted by the anterior pituitary, exists in three major forms in circulation. The macroprolactin form is biologically inactive but contributes to elevated serum prolactin concentrations. Precipitation of macroprolactin by polyethylene glycol (PEG) is widely used in clinical laboratories for the screening of macroprolactin. The aim of this study was two-fold. Firstly, we sought to establish locally relevant reference intervals for serum prolactin and post-PEG precipitation prolactin concentrations in both genders on the Roche Cobas Prolactin II electrochemiluminescence immunoassay. Secondly, the prolactin concentrations after precipitation by PEG dissolved in phosphate-buffered saline (post-PEG(PBS)) were compared with those after precipitation by PEG dissolved in deionised water (PEG(diH2O)). Prolactin concentrations were measured by using the Prolactin Gen II assay on a Roche Cobas e601 analyser. Recoveries of prolactin after precipitation by PEG in PBS and PEG in diH2O were 64.7%–115.8% and 60.9–100.8%, respectively. Post-PEG (PBS) prolactin concentrations were not statistically different from post-PEG (diH2O) prolactin concentrations in either gender.

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Serum prolactin revisited: parametric reference intervals and cross platform evaluation of polyethylene glycol precipitation-based methods for discrimination between hyperprolactinemia and macroprolactinemia

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2016-0902 ◽

2017 ◽

Vol 55 (11) ◽

Cited By ~ 6

Author(s):

Martin Overgaard ◽

Susanne Møller Pedersen

Keyword(s):

Polyethylene Glycol ◽

Elevated Serum ◽

Gel Filtration ◽

Reference Interval ◽

Reference Intervals ◽

Serum Prolactin ◽

Specific Reference ◽

Screening Methods ◽

Discriminative Ability ◽

Discrimination Methods

AbstractBackground:Hyperprolactinemia diagnosis and treatment is often compromised by the presence of biologically inactive and clinically irrelevant higher-molecular-weight complexes of prolactin, macroprolactin. The objective of this study was to evaluate the performance of two macroprolactin screening regimes across commonly used automated immunoassay platforms.Methods:Parametric total and monomeric gender-specific reference intervals were determined for six immunoassay methods using female (n=96) and male sera (n=127) from healthy donors. The reference intervals were validated using 27 hyperprolactinemic and macroprolactinemic sera, whose presence of monomeric and macroforms of prolactin were determined using gel filtration chromatography (GFC).Results:Normative data for six prolactin assays included the range of values (2.5th–97.5th percentiles). Validation sera (hyperprolactinemic and macroprolactinemic; n=27) showed higher discordant classification [mean=2.8; 95% confidence interval (CI) 1.2–4.4] for the monomer reference interval method compared to the post-polyethylene glycol (PEG) recovery cutoff method (mean=1.8; 95% CI 0.8–2.8). The two monomer/macroprolactin discrimination methods did not differ significantly (p=0.089). Among macroprolactinemic sera evaluated by both discrimination methods, the Cobas and Architect/Kryptor prolactin assays showed the lowest and the highest number of misclassifications, respectively.Conclusions:Current automated immunoassays for prolactin testing require macroprolactin screening methods based on PEG precipitation in order to discriminate truly from falsely elevated serum prolactin. While the recovery cutoff and monomeric reference interval macroprolactin screening methods demonstrate similar discriminative ability, the latter method also provides the clinician with an easy interpretable monomeric prolactin concentration along with a monomeric reference interval.

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Age and Gender-Specific Reference Intervals for ProGRP in Healthy Chinese Han Ethnic Adults using the Roche Cobas Immunoassay

Clinical Laboratory ◽

10.7754/clin.lab.2018.171132 ◽

2018 ◽

Vol 64 (06/2018) ◽

Author(s):

Yanhui Zhu ◽

Yulin Yuan ◽

Xiafang Yang ◽

Qiuwei Lu ◽

Xiaoxu Lu ◽

...

Keyword(s):

Reference Intervals ◽

Specific Reference ◽

Chinese Han ◽

Age And Gender ◽

Healthy Chinese ◽

And Gender ◽

Gender Specific ◽

Roche Cobas

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Age- and gender-specific reference intervals for total homocysteine and methylmalonic acid in plasma before and after vitamin supplementation

Clinical Chemistry ◽

10.1093/clinchem/42.4.630 ◽

1996 ◽

Vol 42 (4) ◽

pp. 630-636 ◽

Cited By ~ 155

Author(s):

K Rasmussen ◽

J Møller ◽

M Lyngbak ◽

A M Pedersen ◽

L Dybkjaer

Keyword(s):

Folic Acid ◽

Methylmalonic Acid ◽

Reference Intervals ◽

Vitamin Supplementation ◽

Specific Reference ◽

Age And Gender ◽

Before And After ◽

Total Homocysteine ◽

And Gender ◽

Gender Specific

Abstract We present reference intervals for total homocysteine and methylmalonic acid in plasma based on samples from 126 women (ages 20-85 years, median 49 years) and 109 men (ages 20-84 years, median 50 years). The central 0.95 interval for methylmalonic acid was 0.08-0.28 micromol/L. Supplementation with cyanocobalamin caused a nonsignificant decrease in methylmalonic acid. Supplementation with folic acid caused a decrease in homocysteine concentrations, with data analysis identifying two significantly different clusters: 182 subjects with the lowest initial concentrations (7.76 +/- 1.54 micromol/L, mean +/- SD) and the smallest decrease (1.26 +/- 0.96 micromol/L), and 53 subjects with the highest initial concentrations (12.33 +/- 2.04 micromol/L) and greatest decrease (4.14 +/- 1.32 micromol/L). We argue in favor of the age- and gender-specific central 0.95 intervals obtained for the 182 subjects before being supplemented with folic acid: 4.6-8.1 micromol/L for subjects at <30 years; 4.5-7.9 micromol/L for women, ages 30-59 years; 6.3-11.2 micromol/L for men, ages 30-59 years; and 5.8-11.9 micromol/L for subjects at >60 years.

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Age- and Gender-Specific Reference Intervals for Fasting Blood Glucose and Lipid Levels in School Children Measured With Abbott Architect c8000 Chemistry Analyzer

Indian Journal of Clinical Biochemistry ◽

10.1007/s12291-012-0195-x ◽

2012 ◽

Vol 27 (2) ◽

pp. 141-146 ◽

Cited By ~ 4

Author(s):

Waleed Tamimi ◽

Esam Albanyan ◽

Yasmin Altwaijri ◽

Hani Tamim ◽

Fahad Alhussein

Keyword(s):

Blood Glucose ◽

School Children ◽

Fasting Blood Glucose ◽

Reference Intervals ◽

Specific Reference ◽

Lipid Levels ◽

Age And Gender ◽

And Gender ◽

Gender Specific ◽

Abbott Architect

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Processing-independent proANP measurement for low concentrations in plasma: reference intervals and effect of body mass index and plasma glucose

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2017-0309 ◽

2017 ◽

Vol 56 (1) ◽

Author(s):

Peter D. Mark ◽

Ingrid Hunter ◽

Dijana Terzic ◽

Jens P. Goetze

Keyword(s):

Body Mass Index ◽

Body Mass ◽

Plasma Glucose ◽

Age Groups ◽

Radioactive Tracer ◽

Reference Intervals ◽

Specific Reference ◽

Regression Analyses ◽

Obesity And Diabetes ◽

Gender Specific

AbstractBackground:Decreased concentrations of pro-atrial-derived natriuretic peptides (proABP) in plasma have been associated with obesity and suggested as a predictor of type 2 diabetes. However, assays for measuring proANP are generally aimed to quantitate higher concentrations of proANP associated with cardiac disease. Therefore, we aimed to measure plasma proANP concentrations in a non-obese Scandinavian reference material and evaluate potential associations of plasma proANP with body mass index (BMI) and plasma glucose, respectively.Methods:We report an optimized processing-independent assay (PIA) for proANP in the lower concentration range. The assay was optimized by raising the amount of radioactive tracer and modifying the mixing ratio of resuspended plasma and buffer. Blood samples from a Scandinavian plasma cohort of 693 healthy subjects were then analyzed and age and gender-specific reference intervals were determined.Results:Simple linear regression analyses of proANP and both BMI and plasma glucose in fasting subjects displayed insignificant associations. Multiple regression analyses supported these findings. However, a higher median plasma concentration of proANP was noted among women <50 years compared to men, whereas no gender-specific differences were seen in other age groups.Conclusions:Our results show that in a healthy non-obese population, BMI and plasma glucose in fasting subjects do not affect plasma proANP concentrations. Our method should be considered for future studies on low proANP concentration studies, e.g. in obesity and diabetes.

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Age-specific and sex-specific reference intervals for non-fasting lipids and apolipoproteins in 7260 healthy Chinese children and adolescents measured with an Olympus AU5400 analyser: a cross-sectional study

BMJ Open ◽

10.1136/bmjopen-2019-030201 ◽

2019 ◽

Vol 9 (8) ◽

pp. e030201

Author(s):

Junjie Liu ◽

Yanpeng Dai ◽

Enwu Yuan ◽

Yushan Li ◽

Quanxian Wang ◽

...

Keyword(s):

Children And Adolescents ◽

Density Lipoprotein ◽

Reference Intervals ◽

Chinese Children ◽

Lipoprotein Cholesterol ◽

Specific Reference ◽

Healthy Chinese ◽

And Gender ◽

Gender Specific ◽

Chinese Children And Adolescents

AimsEthnic, demographic, lifestyle, genetic and environmental factors influence lipids and apolipoproteins. The aim of this study was to establish age-specific and gender-specific reference intervals for non-fasting lipids and apolipoproteins in healthy Chinese children and adolescents.MethodsThis study followed the Clinical and Laboratory Standards Institute EP28-A3c guidelines. Non-fasting samples were collected from 7260 healthy Chinese children and adolescents, and they were analysed using the Olympus AU5400 analyser for: triglycerides, total cholesterol (TC), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol (LDL-C), apolipoprotein A1 and apolipoprotein B (ApoB). The age-related and gender-related reference intervals were partitioned using the Harris-Boyd method. The non-parametric method was used to establish the lower limit (2.5th percentile) and the upper limit (97.5th percentile) for the reference intervals. The 90% CIs for the lower and upper limits were also calculated.ResultsBased on the Harris-Boyd method, gender partitions were required for TC, LDL-C and ApoB. Age differences were observed for all analytes. Paediatric reference intervals were established for non-fasting lipids and apolipoproteins based on a large population of healthy children and adolescents.ConclusionsPreviously used reference intervals did not take age and gender into account. These age-specific and gender-specific reference intervals established in this study may contribute to improved management and assessment of paediatric diseases.

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