Requirement for specific gravity and creatinine adjustments for urinary steroids and luteinizing hormone concentrations in adolescents

Urinary gonadotropin assay on 24-h collections as a tool to detect early central puberty onset in girls: determination of predictive thresholds

STUDY QUESTION

Is the 24-h urinary gonadotropin assay an effective diagnostic tool in central precocious puberty (CPP) in girls?

SUMMARY ANSWER

This study is the first to provide 24-h urinary gonadotropin assay data, using an electrochemiluminescent immunoassay (CMIA), and to report its usefulness as a tool for the diagnosis of CPP.

WHAT IS KNOWN ALREADY

Data about the GnRH test in the diagnosis of CPP are variable and there is no consensus regarding its interpretation. The measurement of FSH and LH in urines was previously reported to be an alternative biological tool.

STUDY DESIGN, SIZE, DURATION

This is a retrospective two-cohort study, involving a setting and a validation cohort. A total of 516 girls, included between October 2012 and July 2015, and 632 urinary collections were analyzed in the setting cohort. In the validation cohort, 39 girls were included between January 2021 and May 2023, and 49 urinary collections were analyzed.

PARTICIPANTS/MATERIALS, SETTING, METHODS

This study included girls who consulted for an investigation of disturbed growth rate or a clinical suspicion of puberty onset in different medical centres across France (setting cohort). Girls with a suspicion of precocious puberty onset were addressed at the expert centre of paediatric endocrinology of the Groupement Hospitalier Lyon Est (validation cohort). Pelvic ultrasonography was performed and enabled their classification according to clinical and morphologic changes criteria (prepubertal or pubertal groups). The parents collected 24-h urine samples (u24) according to standardized instructions. FSH and LH (urinary or plasmatic) were measured using a current and automated CMIA.

MAIN RESULTS AND THE ROLE OF CHANCE

The area under the ROC curves for CPP prediction was 0.709 for u24FSH (P < 0.001), 0.767 for u24LH (P < 0.001), and 0.753 for the u24LH/u24FSH ratio (P < 0.001). We retained all possible combinations of the four thresholds in the validation cohort (u24FSH = 1.1 or 2.0 IU/24 h; u24LH = 0.035 or 0.08 IU/24 h). The combination of u24FSH > 1.1 IU/24 h and u24LH > 0.08 IU/24 h had a positive PV of 85.7% and a negative PV of 94.3%, a sensitivity of 85.7% and a specificity of 94.3%, for classifying prepubertal and pubertal girls in this cohort.

LIMITATIONS, REASONS FOR CAUTION

This is a retrospective study, in which a margin of error remains due to the inherent uncertainty regarding the clinical assessment of pubertal onset. It must be considered that the thresholds can only apply to the used reagents; measurements without extractions using other reagents are likely to show important heterogeneity.

WIDER IMPLICATIONS OF THE FINDINGS

The assay performed herein is a simple, non-invasive, and analytically robust technique meeting the criteria for an alternative to the GnRH test which could be used to supplement its lack of sensitivity.

STUDY FUNDING/COMPETING INTEREST(S)

No specific funding was used. All authors declared no conflict of interest.

TRIAL REGISTRATION NUMBER

In-house #23-5214 registered study.

Enantiomer-specific burden of metalaxyl and myclobutanil in non-occupationally exposed population with evidence from dietary intake and urinary excretion

Metalaxyl (MET) and myclobutanil (MYC) are two widely used chiral fungicides that may pose health risks to non-occupationally exposed populations. Here, the two fungicides were enantiomer-specific quantified in the dietary food and urine of residents in an Eastern China city, to determine the exposure and excretion of these contaminants in different populations. Results indicate that residues of MET and MYC varied with different food items at 0.42-0.86 ng/g fresh weight (FW) and 0.18-0.33 ng/g FW, respectively. In urine samples, the residual levels after creatinine adjusting (CR) ranged from 10.2 to 1715.4 ng/g CR for MET and were below the detection limit up to 320.7 ng/g CR for MYC. Significant age- and gender-related differences were separately found in urinary MET and MYC of different populations. Monte-Carlo simulations suggested that children had higher daily dietary intake (DDI) but lower urinary excretion (DUE) rates than youths, and thus may suffer higher body burdens. The residues of antifungally ineffective enantiomers (S-MET and R-MYC) were slightly higher than their antipodes in foods. Moreover, the enantiomer-selective urinary excretion resulted in higher retention of S-MET and R-MYC in the human body. Our results suggest that both dietary intake and urinary excretion should be enantiomer-specifically considered when assessing the exposure risk and body burden of chiral fungicides in the non-occupationally exposed population. Furthermore, substitutive application of enantiomer-enriched fungicide formulations can not only benefit the antifungal efficacy but also be safer for human health.

Association of urinary sex hormones with mood and behavior changes in a community adolescent cohort

OBJECTIVE

To examine the contribution of variation in sex hormone excretion to mood and behavioral changes in adolescent females and males.

DESIGN

Prospective, longitudinal observational cohort study.

METHODS

Participants were 342 volunteers aged 10-12 years living in rural Australia. Urinary estradiol and testosterone levels measured by liquid chromatography-mass spectrometry were obtained at three-month intervals for three years. Integrated measures (area-under-curve) of urinary steroid excretion summarised as absolute and variability during each 12-month period of the study. Psychosocial data were gathered annually with the primary outcome of depressive symptomatology. Secondary outcomes were the other subscales of the Youth Self-Report, impulsive-aggression, sleep habits, and self-harm.

RESULTS

277 (158 male) participants contributed data over the full duration of the study and could be included in the analyses. In females, analyses of absolute urine hormone levels found no relationship between estradiol and any outcome, but higher testosterone was significantly associated with depression and poorer sleep. Greater variability of both urine estradiol and testosterone was associated with lower total psychopathology, anxious/depressed and social problems scores. Greater variability in urine estradiol was associated with lower attention problems and impulsive aggression in females. In males, higher testosterone and estradiol levels were associated with rule-breaking, and poorer sleep, and no associations were found for gonadal hormone variability for males.

CONCLUSIONS

Longitudinal measurement of both iso-sexual and contra-sexual gonadal hormones contributes to a more nuanced view of the impact of sex steroids on mood and behavior in adolescents. These findings may enlighten the understanding of the impact of sex steroids during normal male and female puberty with implications for hormone replacement therapies as well as management of common mood and behavioral problems.

Exposure to phthalates and DiNCH among preschool children in Sweden: Urinary metabolite concentrations and predictors of exposure

Several plasticizing chemicals induce endocrine disrupting effects in humans, and the indoor environment is suggested to be a source of exposure. As children are particularly vulnerable to the effects from exposure to endocrine disrupting chemicals (EDCs), it is essential to monitor exposure to EDCs such as phthalates and non-phthalate plasticizers in indoor environments intended for use by children. The aim of this study was to assess everyday plasticizer exposure among preschool-aged children in Sweden by measuring urinary plasticizer metabolite concentrations. In addition, it was investigated whether the concentrations would be altered as a result of the children spending part of the day at preschool, in comparison with weekend exposure, when they may spend more time in home environments or engage in various weekend and leisure activities. For this purpose, fourteen metabolites from eight phthalates (di-ethylhexyl phthalate, DEHP; di-n-butyl phthalate, DnBP; di-isobutyl phthalate, DiBP; butyl-benzyl phthalate, BBzP; di-iso-nonyl phthalate, DiNP; di-propylheptyl phthalate, DPHP; di-iso-decyl phthalate, DiDP; and di-ethyl phthalate, DEP) and one non-phthalate plasticizer (di-isononyl cyclohexane 1,2-dicarboxylate, DiNCH) were measured in 206 urine samples collected at four occasions, i.e. twice during the winter and twice during the spring from 54 children (mean 5.1 years, SD 0.94) enrolled at eight preschools in Sweden. A detection frequency (DF) of 99.9% for the 14 metabolites indicates a widespread exposure to plasticizers among children in Sweden. Compared to previous Swedish and international studies performed during approximately the same time period, high urinary concentrations of monobenzyl phthalate (MBzP), a metabolite from the strictly regulated BBzP, were measured in this study (median 17 ng/mL). Overall, high urinary phthalate metabolite concentrations were observed in this study compared to the US CDC-NHANES from the same time period and similar age-group. Compared to European studies, however, similar concentrations were observed for most metabolites and the urinary concentrations from few participating children exceeded the human biomonitoring guidance values (HBM-GV) for children. After days with preschool attendance, lower urinary concentrations of metabolites originating from DEP and phthalates that are strictly regulated within the EU REACH legislation (DEHP, DnBP, and DiBP) and higher concentrations of metabolites originating from DiNP, DPHP, and DiDP, i.e. less or non-regulated phthalates were found compared the urinary concentrations of these metabolites in weekends. This may indicate that factors in the indoor environment itself are important for the extent of the plasticizer exposure. All the analyzed metabolites were measured in lower concentrations in urine collected from children attending preschools built or renovated after the year 2000, while no seasonal differences were observed in this study.

Associations of benzotriazoles and benzothiazoles with estrogens and androgens among pregnant women: A cohort study with repeated measurements

People are extensively exposed to benzotriazoles (BTRs) and benzothiazoles (BTHs) derivatives, which are environmental pollutants that may possess endocrine-disrupting potential; however, no epidemiological evidence is available on the associations of BTRs and BTHs with estrogens and androgens. This study aimed at investigating the associations of BTRs and BTHs with estrogens and androgens among pregnant women. Based on a prospective cohort study, we included 459 pregnant women who donated a complete serial of urine samples at each trimester and had repeated measurements of four BTRs, four BTHs, three estrogens (estrone, 17β-estradiol, and estrio), and two androgens (dehydroepiandrosterone and testosterone) in the urine samples. Associations of repeatedly measured BTRs and BTHs with maternal urinary estrogens and androgens were analyzed, and the cross-sectional associations were also analyzed. Tolyltriazole (TTR) (≥59.3%) and benzothiazole (BTH) (≥93.5%) had the highest detection rate among the BTRs and BTHs, respectively. Repeated measurement analysis and cross-sectional analysis consistently found the target BTRs and BTHs were positively associated with 17β-estradiol, estriol, and testosterone, while the trend of the associations with estrone and dehydroepiandrosterone was inconsistent. Among the positive associations with 17β-estradiol, estriol, and testosterone, the percent of change in estriol associated with TTR was the most prominent [28.5% (95% confidential interval: 24.2%, 32.9%) for each doubling in TTR]. The significant associations with estrone, estriol, testosterone, and dehydroepiandrosterone were stronger among pregnant women who gave birth to a boy than those who gave birth to a girl. These findings add epidemiological evidence on the endocrine-disrupting potential of BTRs and BTHs and highlight the importance of focusing on the health outcomes of BTRs and BTHs related to disturbed estrogens and androgens. Future studies are needed to validate these findings and explore the underlying mechanisms.

Ritalinic acid in urine: Impact of age and dose

Objectives

The objective of this work was to study the results of urine drug testing for ritalinic acid (RA), the major urinary metabolite of methylphenidate (MP) (e.g., Ritalin®). The impact of age from 4 to 65 years old and older on median levels of RA was investigated as well as potential variations in pH, specific gravity and creatinine content of the patient urine samples.

Design and Methods

Samples from patients who were 1) prescribed MP and found to be positive for RA, 2) prescribed MP but found to be negative for RA and 3) not prescribed MP but tested positive for RA were examined by liquid chromatography – mass spectrometry/mass spectrometry (LC-MS/MS) for RA concentration. The levels of RA were examined for median and average levels and further normalized and transformed to reveal a near gaussian distribution.

Results

Over 20,000 samples from patients who were prescribed MP were examined for this work. Analysis of these data for a subset of patients prescribed MP and testing positive for RA revealed statistically different median values of RA for school age patients of 6 years old through 17 years old from adult patients 18 through 64 years old. Another 6751 samples were positive for RA without a prescription but were not included in the overall assessment of these data.

Conclusions

While not clear as to the reason, these data indicate that school age children under the age of 18 have much higher levels of RA than adult patients. These results can be used to estimate “normal” levels of RA in these chronically dosed populations.

Single random measurement of urinary gonadotropin concentration for screening and monitoring girls with central precocious puberty

PURPOSE

The gold standard for assessing pubertal activation is the gonadotropinreleasing hormone (GnRH) stimulation test (GnRHST), which is invasive, timeconsuming, and inconvenient. This study evaluated whether a single random measurement of urinary luteinizing hormone (LH) concentration could substitute for the GnRHST in diagnosing and monitoring central precocious puberty (CPP) in girls.

METHODS

Fifty-five girls with breast buds before 8 years of age were assessed by both the GnRHST and urinary gonadotropin assays. Based on the GnRHST results, 29 girls were assigned to the CPP group (peak LH≥5 IU/L), and 26 were placed in the premature thelarche (PT) group (peak LH&lt;5 IU/L). Auxological data and urine and serum samples were collected at baseline and after treatment with a GnRH agonist for 12 and 24 weeks.

RESULTS

Although the auxological data did not differ between the 2 groups, the serum levels of insulin-like growth factor-1, basal LH, follicle-stimulating hormone (FSH), estradiol, and peak LH; urinary LH; and peak serum LH/FSH and urinary LH/FSH ratios were higher in the CPP group than in the PT group. Pearson correlation analysis showed a positive correlation between the urinary and serum LH concentrations (r=0.660, P&lt;0.001). Receiver-operating characteristic curve analyses showed that a urinary LH concentration of 0.725 IU/L was a cutoff that significantly predicted positivity on the GnRHST. Urinary LH and FSH concentrations declined significantly during GnRH agonist treatment.

CONCLUSION

A single, random measurement of urinary gonadotropin concentration could be a reliable tool for initial screening and therapeutic monitoring of CPP in girls.

Urinary Isoflavones Levels in Relation to Serum Thyroid Hormone Concentrations in Female and Male Adults in the U.S. General Population

Isoflavones are phytoestrogens found in plant-based foods and nutritional supplements. Experimental studies show a positive association between isoflavones and hypothyroidism, but epidemiological findings are conflicting. We used multivariable linear regression to examine the association between urinary isoflavone concentrations and serum thyroid hormone concentrations in the National Health and Nutrition Examination Survey (2007-2010). In this study, we found that Daidzein and O-DMA associations with free T4 were stronger among women: a 10-fold increase in daidzein was associated with a 3.2% (95% CI: 1.9%, 4.5%) increase in women and a 0.6% (95% CI: -1.7%, 0.6%) decrease in men and a 10-fold increase in O-DMA was related to a 2.0% (95% CI: 1.1%, 2.9%) increase in women and a 0.3% (95% CI: -1.2%, 0.5%) decrease in men. In this study, selected urinary isoflavone concentrations were associated with serum thyroid hormone concentration in a sex-dependent fashion.

Alternative Splicing Dynamics of the Hypothalamus-Pituitary-Ovary Axis During Pubertal Transition in Gilts

The timing of puberty in mammals marks the point at which reproduction becomes possible. Abnormalities in the timing of puberty may exert a series of negative effects on subsequent health outcomes. Alternative splicing (AS) has not only emerged as a significant factor in the transcription of genes but it is also reported to play a role in the timing of puberty. However, to date, the changes and dynamics of AS during the onset of puberty is extremely seldom explored. In the present study, we used gilts as a research model to investigated the dynamics of AS and differentially expressed AS (DEAS) events within the hypothalamus-pituitary-ovary (HPO) axis across pre-, in-, and post-puberty. We detected 3,390, 6,098, and 9,085 DEAS events in the hypothalamus, pituitary, and ovary when compared across pre-, in-, and post-pubertal stages, respectively. Within the entire HPO axis, we also identified 22,889, 22,857, and 21,055 DEAS events in the pre-, in-, and post-pubertal stages, respectively. Further analysis revealed that the differentially spliced genes (DSGs) associated with staged DEAS events were likely to be enriched in the oxytocin signaling pathway, thyroid hormone signaling pathway, GnRH signaling pathway, and oocyte meiosis signaling pathway. The DSGs associated with DEAS events across the entire HPO axis were enriched in endocytosis signaling pathway, the MAPK signaling pathway, and the Rap1 signaling pathway. Moreover. the ASs of TAC1, TACR3, CYP19A1, ESR1, ESRRA, and FSHR were likely to regulate the functions of the certain HPO tissues during the onset of puberty. Collectively, the AS dynamics and DEAS events were comprehensively profiled in hypothalamus, pituitary, and ovary across the pre-, in-, and post-pubertal stages in pigs. These findings may enhance our knowledge of how puberty is regulated by AS and shed new light on the molecular mechanisms underlying the timing of puberty in mammals.

Environmental doses of arsenic exposure are associated with increased reproductive-age male urinary hormone excretion and in vitro Leydig cell steroidogenesis

Humans are ubiquitously exposed to arsenic from multiple sources, and chronic arsenic exposure may be associated with male reproductive health. Although association regarding arsenic exposure and sex hormone secretion in blood has been reported, sex hormone excretion in urine studies is lacking. Urinary sex hormone excretion has emerged as a complementary strategy to evaluate gonadal function. Herein, we determined the associations between environmental exposure to arsenic and urinary sex hormone elimination and in vitro Leydig cell steroidogenesis. Concentrations of arsenic and testosterone (T), estradiol (E₂) and progesterone (P) in repeated urine samples were determined among 451 reproductive-age males. Moreover, an in vitro Leydig cell MLTC-1 steroidogenesis experiment was designed to simulate real-world scenarios of low human exposure. Multivariable linear regression models were used to assess the associations of urinary arsenic levels with urinary hormones. Urinary arsenic concentrations were positively associated with urinary sex hormone (T, E₂, and P) levels. An in vitro test further demonstrated that a population-based environmental exposure range (0.01-5 μM) of arsenic induced Leydig cell steroidogenesis potency. Our results indicate that low-dose arsenic exposure exhibits an endocrine disrupting effect by stimulating Leydig cell steroidogenesis and accelerating urinary steroid excretion, which extends previous knowledge of the inverse association of high-dose arsenic exposure with sexual steroid production that is assumed to be anti-androgen.

Comparison of Pteridine Normalization Methods in Urine for Detection of Bladder Cancer

Pterin compounds belong to the group of biomarkers for which an increase in interest has been observed in recent years. Available literature data point to this group of compounds as potential biomarkers for cancer detection, although the biochemical justification for this claim is not yet fully understood. The aim of this study was to evaluate the usefulness of pterin compounds in the diagnosis of bladder cancer, with particular emphasis on the role of creatinine and the specific gravity of urine as factors for normalizing the concentration of pterin compounds in urine. The standardization of the concentration of pterin compounds to urine specific gravity allows the building of better classification models for screening patients with potential cancer of the bladder. Of the compounds that make up the pterin profile, isoxanthopterin appears to be a compound that can potentially be described as a biomarker of bladder cancer.

Bumpy and Smoother Pathways of Puberty Hormone Change: A Novel Way to Define Gonadal Hormone Trajectories in Adolescents

CONTEXT

The study of gonadal hormone effects on adolescent wellbeing has been limited by logistical challenges. Urine hormone profiling offers new opportunities to understand the health and behavioral implications of puberty hormones.

OBJECTIVE

To characterize pubertal change in urinary testosterone and estradiol among male and female adolescents, respectively.

DESIGN

Three-year prospective cohort study.

SETTING

Australian regional community.

PARTICIPANTS

282 (163 male) normally developing adolescents aged 11.8 ± 1.0 years at baseline.

MAIN OUTCOME MEASURE

Quarterly urine measurements of testosterone and estradiol (mass spectrometry); annual anthropometric assessment and Tanner stage (TS) self-report.

RESULTS

Two-class sigmoidal and quadratic growth mixture models (centered on age at TS3) were identified as best-fit for describing testosterone (male) and estradiol (female) change. Classes 1 (male: 63%; female: 82%) and 2 (male: 37%; female: 18%) were respectively named the "stable" and "unstable" trajectories, characterized by different standard deviation of quarterly hormone change and magnitude of hormone peaks and troughs (all P < 0.001). Compared with class 1 (stable), class 2 males were taller at baseline (154 vs 151 cm), reported earlier and faster TS progression (P < 0.01), and showed higher serum testosterone levels at baseline and 3 years (P ≤ 0.01). Class 2 females exhibited smaller height and weight gains over the 3 years and had higher baseline serum estradiol (249 vs 98 pmol/L; P = 0.002) than class 1.

CONCLUSIONS

Adolescents showed 2 distinct urinary gonadal hormone trajectories, characterized by stability of change over time, which were not associated with consistent anthropometric differences. Results provide a methodology for studying gonadal hormone impacts on other aspects of biopsychosocial wellbeing. Identification of potential "at-risk" hormone groups would be important for planning supportive interventions.

Foot Length Growth as a Novel Marker of Early Puberty

Foot growth is part of overall pubertal growth but its relation to other anthropometric and hormonal changes is unclear. Our objective was to determine how foot length changes relate to changes in other growth parameters (height and weight), Tanner stage, and serum hormones. Adolescents (n = 342) were recruited to a 3-year longitudinal cohort study, underwent annual anthropometric assessments (height, weight, and foot length), and provided self-rated Tanner staging. They also provided blood samples that were analyzed using liquid chromatography-tandem mass spectrometry for serum testosterone and estradiol and classified as pre-pubertal or pubertal based on circulating hormone levels. Average annual percent increase in foot length was greater for pre-pubertal adolescents compared with pubertal. Increased foot length was associated with increases in height, weight, Tanner stage, and serum hormones in males and pre-menarcheal females but not post-menarcheal females. Foot length offers a novel, noninvasive, cost-effective, and easily demonstrable marker of early pubertal changes.

Quantitative metabolic profiling of urinary eicosanoids for clinical phenotyping

The eicosanoids are a family of lipid mediators of pain and inflammation involved in multiple pathologies, including asthma, hypertension, cancer, atherosclerosis, and neurodegenerative diseases. These signaling mediators act locally, but are rapidly metabolized and transported to the systemic circulation as a mixture of primary and secondary metabolites. Accordingly, urine has become a useful readily accessible biofluid for monitoring the endogenous synthesis of these molecules. Herein, we present the validation of a rapid, repeatable, and precise method for the extraction and quantification of 32 eicosanoid urinary metabolites by LC-MS/MS. For 12 out of 17 deconjugated glucuronide eicosanoids, there was no improvement in recovered signal. These metabolites cover the major synthetic pathways, including prostaglandins, leukotrienes, and isoprostanes. The method linearity was >0.99 for all metabolites analyzed, the limit of detection ranged from 0.05-5 ng/ml, and the average extraction recoveries were >90%. All analytes were stable for at least three freeze/thaw cycles. The method was formatted for large-scale analysis of clinical cohorts, and the long-term repeatability was demonstrated over 15 months of acquisition, evidencing high precision (CV <15%, except for tetranorPGEM and 2,3-dinor-11β-PGF_2α, which were <30%). The presented method is suitable for focused mechanistic studies as well as large-scale clinical and epidemiological studies that require repeatable methods capable of producing data that can be concatenated across multiple cohorts.

Urinary Sex Steroids and Anthropometric Markers of Puberty - A Novel Approach to Characterising Within-Person Changes of Puberty Hormones

Background/Aims

The longitudinal relationships of within-individual hormone and anthropometric changes during puberty have not ever been fully described. The objectives of this study were to demonstrate that 3 monthly urine collection was feasible in young adolescents and to utilise liquid chromatography-tandem mass spectrometry assay methods for serum and urine testosterone (T), estradiol (E₂) and luteinizing hormone (LH) in adolescents by relating temporal changes in urine and serum hormones over 12 months to standard measures of pubertal development.

Methods

A community sample of 104 adolescents (57 female) was studied over 12 months with annual anthropometric assessment, blood sampling and self-rated Tanner staging and urine collected every 3 months. Serum and urine sex steroids (T, E₂) were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and LH by immunoassay.

Results

A high proportion (92%) of scheduled samples were obtained with low attrition rate of 6.7% over the 12 months. Urine hormone measurements correlated cross-sectionally and longitudinally with age, anthropometry and Tanner stage.

Conclusion

We have developed a feasible and valid sampling methodology and measurements for puberty hormones in urine, which allows a sampling frequency by which individual pubertal progression in adolescents can be described in depth.