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Quantitation of endogenous steroids and their precursors is essential for diagnosis of a wide range of endocrine disorders. Usually, these analyses have been carried out using immunoassays. However, immunoassays often overestimate concentrations due to assay interference by other endogenous steroids, especially for low concentrations. Mass spectrometry based methods offer superior specificity, accuracy, and sensitivity. We therefore present a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method with automated sample preparation for determination of 17α-hydroxyprogesterone (17OHP), cortisol, cortisone, dehydroepiandrosterone sulfate (DHEAS), androstenedione (A4), testosterone (T), and estrone sulfate (E1S). Samples were prepared using protein precipitation and 96-well filter plates, fully automated in a pipetting robot and analyzed by LC-MS/MS. Serum samples from 187 healthy children and adolescents aged 5-18 years were used to study hormone changes in relation to sex and pubertal stage. Lower limit of quantification for 17OHP was 0.7 nmol/L, for cortisol 11 nmol/L, for cortisone 2 nmol/L, for DHEAS 0.1 µmol/L, and for A4, T, and E1S, 0.2 nmol/L. This study showed a general increase in 17OHP, DHEAS, A4, T and E1S in both genders during puberty. In boys, A4 and T increased significantly throughout pubertal development. Girls had significantly higher A4 and E1S concentrations, while boys had higher T concentrations. No sex- or puberty-specific differences were seen in cortisol or cortisone concentrations. To the best of our knowledge, this is the first presentation of changes in serum E1S concentrations during pubertal development in healthy children. [ABSTRACT FROM AUTHOR]

Highlights • A GC–MS/MS based method for quantification of sex steroids in children is presented. • Adrostenedione, dihydrotestosterone, testosterone, estrone, estradiol were analyzed. • The GC–MS/MS- based method was sensitive enough for use in pediatric applications. • Reference intervals were established in relation to sex and pubertal maturation. Abstract Background Androgen and estrogen determinations serve as important diagnostic markers in a variety of clinical conditions. However, one challenge is to enhance assay sensitivity for determination in the lowest range, such as in prepubertal children. We here present a recently developed gas chromatography–tandem mass spectrometry (GC–MS/MS) method for determination of androstenedione (A 4), dihydrotestosterone (DHT), testosterone (T), estrone (E 1), and estradiol (E 2) in children, which we have compared with the sensitive radioimmunoassays; E 2 extraction-RIA and T-RIA. Methods Steroids were extracted in ethyl acetate n-hexane solution from serum spiked with isotopically labeled internal standard and derivatized sequentially with pentafluorobenzyl bromide, pentafluorobenzyl hydroxylamine and pentafluoropropionic acid anhydride and analyzed by GC–MS/MS using a triple quadrupole mass spectrometer operated in negative chemical ionization mode. Leftover routine samples (n = 414) were used to evaluate the concordance between GC–MS/MS and RIAs and the validity of GC–MS/MS for pediatrics; of these samples, 101 were from seemingly healthy children. Pubertal stage was recorded for reference interval evaluation. Results Lower limit of detection for A 4 , T, DHT, E 1 , and E 2 were 0.1 nmol/L, 0.1 nmol/L, 27 pmol/L, 9 pmol/L, and 2 pmol/L, respectively. Good agreement was found between GC–MS/MS and T-RIA (r = 0.98) as well as between GC–MS/MS and E 2 extraction-RIA (r = 0.98, for E 2 concentrations above 14 pmol/L). In boys, T and DHT increased significantly from prepuberty throughout pubertal development, and in girls the same increase was observed for E 1 and E 2. The greatest increase in A 4 for both genders, as well as E 1 and E 2 in boys and T and DHT in girls, occurred in mid to late puberty. Conclusions We report the development of a GC–MS/MS method sensitive enough to accurately determine serum levels of androgens and estrogens in children. [ABSTRACT FROM AUTHOR]

Aim: We aimed to evaluate aspects of pubertal development to identify the most reliable clinical sign of pubertal onset in males. Methods: We performed a mini review of the literature. Results: In 1951 Reynolds and Wines categorised pubic hair growth and genital development in five stages by visual inspection. Today the Tanner scale is used to assess the five stages of pubertal development, The second genital stage, characterised by enlargement of the scrotum defines pubertal onset in males. Testicular volume may be evaluated by using a calliper or by ultrasound scan. The Prader orchidometer, described in 1966, offers a method for evaluating testicular growth by palpation. Pubertal onset is commonly defined as testicular volume >3 or ≥4 mL. The development of sensitive laboratory methods has enabled studies analysing hormonal activity in the hypothalamus‐pituitary‐gonadal axis. We review the relationships between physical and hormonal signs of puberty. We also discuss the results of studies assessing different aspects of pubertal development with a focus on identifying the most reliable clinical sign of pubertal onset in males. Conclusion: A substantial amount of evidence supports testicular volume of 3 mL as the most reliable clinical sign of male pubertal onset. [ABSTRACT FROM AUTHOR]

Background. Immunoassays have been criticized for poor accuracy at low testosterone concentrations. Mass spectrometry (MS) has been proposed as the only reliable method for testosterone determination. The aim of this study was to compare a sensitive testosterone radioimmunoassay (RIA) with results from different MS. Methods. We compared testosterone concentrations determined by a sensitive testosterone RIA, lower limit of detection 0.03 nmol/L and limit of quantitation 0.1 nmol/L, with four tandem MS that were included in an international external quality assessment program for laboratory medicine. We also compared the morning concentrations of testosterone in girls and boys at different pubertal stages, using results from the RIA, with reported values determined by LC-MS/MS, developed for androgen determination in children. Results. The mean (SD), concentrations were similar between RIA and MS: 1.5 (0.3) and 1.4 (0.4) in the child/women range (0.8-2.6 nmol/L) and 16.0 (3.7) and 17.8 (4.5) nmol/L for the adult male range (10.1-30.0 nmol/L), respectively. The ratio between RIA and MS versus results from mean values of the four MS methods was 1.0 (0.18); 1.1 (0.18) for child/women concentrations and 0.9 (0.13) for male testosterone concentrations. Furthermore, compared to the pediatric reference values determined by LC-MS/MS, the sensitive testosterone RIA delivered similar testosterone values across the different pubertal stages. Conclusions. The comparison between different tandem MS methods and a sensitive testosterone RIA illustrates that there are immunoassays that deliver clinically useful information in prepubertal and pubertal children. [ABSTRACT FROM AUTHOR]

Aim: We investigated longitudinal adrenal androgen concentrations and any relationship between gestational age, birth size, anthropometric parameters and adrenal androgen concentrations during childhood in boys born moderate to late preterm.Methods: This longitudinal, prospective study included 58 boys born at 32+0 to 36+6 weeks of gestation. Dehydroepiandrosterone sulphate and androstenedione were analysed by liquid chromatography-tandem mass spectrometry, and anthropometric data were recorded from 5 to 10 years of age.Results: Dehydroepiandrosterone sulphate concentrations correlated with weight standard deviations scores (SDS) from 7 to 10 years of age and waist-to-height ratios at seven and 10 years of age. Androstenedione correlated with weight SDS from 7 to 10 years of age and waist-to-height ratios at 10 years of age. Longitudinal analysis showed a relationship between weight SDS and waist-to-height SDS and dehydroepiandrosterone sulphate (p < 0.001 and p < 0.001, respectively) and androstenedione (p = 0.002 and p = 0.003, respectively), independently of age.Conclusion: The trajectories of anthropometric parameters and adrenal androgen secretion were consistent from 5 to 10 years of age in this cohort. The body composition reflected by current weight and the waist-to-height ratio, rather than gestational age and birth size, was associated with adrenal androgen secretion. [ABSTRACT FROM AUTHOR]

Objective: The relationship between sex hormone concentrations during childhood and birth weight (BW) is poorly understood. We aimed to investigate this relationship and the associations with anthropometric data at 5, 6, 7, 8, and 10 years of age in preterm boys. Design: A prospective longitudinal single‐centre study, including 58 boys with a BW of 1325–3320 g and gestational age (GA) of 32 + 2 to 36 + 6 weeks. Patients and Measurements: Data on GA, BW and anthropometric data between 5 and 10 years of age were recorded. Testicular development was assessed at 8 and 10 years of age. Serum concentrations of sex steroids were analysed with gas chromatography‐tandem mass spectrometry at 5–10 years and luteinizing hormone (LH) and follicle‐stimulating hormone (FSH) with immunoassays at 10 years of age. Results: At 8 years of age, testosterone and estrone correlated negatively with BW, (ρ = −0.35, p =.021) and (ρ = −0.34, p =.024), respectively. At 10 years of age, testosterone, dihydrotestosterone, estrone and estradiol correlated negatively with BW (ρ = −0.39, p =.010), (ρ = −0.38, p =.013), (ρ = −0.44, p =.003) and (ρ = −0.36, p =.019), respectively. Weight gain from birth correlated with testosterone at 5 years (ρ = 0.40, p =.002), 7 years (ρ = 0.30, p =.040), 8 years (ρ = 0.44, p =.003) and 10 years (ρ = 0.40, p =.008) of age. At 10 years of age, testosterone correlated with LH (ρ = 0.42, p =.006) and FSH (ρ = 0.33, p =.033) but not with testicular volume. Conclusions: Lower BW was associated with increased sex steroid concentrations from 8 years of age, independently of clinical signs of puberty. [ABSTRACT FROM AUTHOR]