Prenatal, newborn and childhood factors and the timing of puberty in boys and girls.

BACKGROUND: Our aim was to determine if prenatal factors, gestational age, birth weight and length, and childhood body mass index (BMI) are associated with the timing of puberty. METHODS: Our population-based study comprised 4826 girls and 5112 boys born between 1997 and 2002. Multiple linear regression modeled the relationships between the maternal and child predictors and the age at peak height velocity (PHV). RESULTS: Maternal smoking throughout pregnancy was associated with earlier age at PHV (-1.8 months in girls, 95%CI = -3.2 to -0.3, p = 0.015 and -1.7 months in boys, 95%CI = -3.1 to -0.3, p = 0.016). Older gestational age predicted later age at PHV in boys. One SDS increase in birth weight led to 1.7 months later age at PHV in girls (95%CI = 1.2 to 2.2, p < 0.001) and 0.8 months in boys (95%CI = 0.2 to 1.3, p = 0.005). At the age of 9 years, each increment of BMI by 1 kg/m2 was associated with 1.7 months (95%CI = -1.9 to -1.6, p < 0.001) and 1.3 months (95%CI = -1.4 to -1.1, p < 0.001) earlier age at PHV in girls and boys, respectively. CONCLUSIONS: Fetal exposure to smoking can potentially exert enduring effects on pubertal timing. Birth weight and childhood nutritional status are significant determinants of pubertal timing in both sexes. IMPACT: Maternal smoking was associated with earlier timing of puberty and greater birth weight with later timing of puberty in both girls and boys. Most previous studies have focused on girls and used surveys to assess pubertal development, but we studied both sexes and used the same objective measure (age at peak height velocity) for the timing of puberty. Our study increases knowledge especially regarding factors associated with the timing of puberty among boys.

Quantification of urinary gonadotropins by specific assays may improve the evaluation of sex-specific hormonal changes in early infancy.

OBJECTIVE: The aim of this study was to investigate the feasibility of different gonadotropin assays for determining total and intact luteinizing hormone (LH), and follicle-stimulating hormone (FSH) immunoreactivity in urine (U-LH-ir and U-FSH-ir, respectively) during early infancy. DESIGN, PATIENTS AND MEASUREMENTS: Morning urine samples were obtained from 31 infants, aged between 0 and 6 months, to study the age-related course of urinary gonadotropins. Additionally, we investigated bi-hourly urine samples of a 5-day-old male neonate for 24 h to observe the course of urinary gonadotropins during a daily cycle. We employed different immunofluorometric assays for measuring total and intact U-LH-ir, and U-FSH-ir. RESULTS: In neonates up to 21 days of age, the U-LH-ir levels measured by the regular LH assay (also detecting hCG) were significantly higher than those determined by the total (specific) LH assays (p = .004). U-FSH-ir was higher in girls than boys during both the first and the next 5 months (p = .02 and p < .001, respectively), whereas total U-LH-ir was higher in boys until 6 months of age (p < .001). Total U-LH-ir/U-FSH-ir ratio was significantly higher in boys than girls across the first half-year (p < .001). CONCLUSIONS: The assessment of total U-LH-ir and U-FSH-ir, and their respective ratio constitutes a noninvasive, practical and scalable tool to investigate sex-specific changes during early infancy, with the ratio being significantly higher in boys than girls. Only highly specific LH assays detecting beta-subunit and its core fragment in addition to intact LH should be used for determining U-LH-ir in the neonatal period to avoid potential cross-reactivity with hCG of placental origin.

Central precocious puberty in boys: secular trend and clinical features.

OBJECTIVE: Recent studies suggest that boys enter puberty at a younger age, and the incidence of male central precocious puberty (CPP) is increasing. In this study, we explore the incidence of male CPP and identify key clinical and auxological indicators for organic CPP (OCPP). DESIGN: A retrospective registry-based study. METHODS: The medical records of 43 boys treated with CPP at the Helsinki University Hospital between 1985 and 2014 were reviewed. Clinical, auxological, and endocrine data of the CPP patients were included in the analyses. RESULTS: Based on brain MRI, 26% of patients had OCPP. Between 2010 and 2014, the CPP incidence in boys was 0.34 per 10 000 (95% CI 0.20-0.60). Between 1990 and 2014, the male CPP incidence increased (incidence rate ratio [IRR] 1.10, P = .001). This increase was driven by rising idiopathic CPP (ICPP) incidence (IRR 1.11, 95% CI 1.05-1.19, P < .001), while OCPP incidence remained stable (P = .41). Compared with the patients with ICPP, the patients with OCPP were younger (P = .006), were shorter (P = .003), and had higher basal serum testosterone levels (P = .038). Combining 2 to 4 of these readily available clinical cues resulted in good to excellent (all, area under the curve 0.84-0.97, P < .001) overall performance, differentiating organic etiology from idiopathic. CONCLUSIONS: The estimated incidence of CPP in boys was 0.34 per 10 000, with 26% of cases associated with intracranial pathology. The increase in CPP incidence was driven by rising ICPP rates. Patients with OCPP were characterized by shorter stature, younger age, and higher basal testosterone levels, providing valuable cues for differentiation in addition to brain MRI. Utilizing multiple cues could guide diagnostic decision-making.

During an 18-month course of automated insulin delivery treatment, children aged 2 to 6 years achieve and maintain a higher time in tight range.

AIMS: To investigate whether the positive effects on glycaemic outcomes of 3-month automated insulin delivery (AID) achieved in 2- to 6-year-old children endure over an extended duration and how AID treatment affects time in tight range (TITR), defined as 3.9-7.8 mmol/L. RESEARCH DESIGN AND METHODS: We analysed 18 months of follow-up data from a non-randomized, prospective, single-arm clinical trial (n = 35) conducted between 2021 and 2023. The main outcome measures were changes in time in range (TIR), glycated haemoglobin (HbA1c), time above range (TAR), TITR, and mean sensor glucose (SG) value during follow-up visits (at 0, 6, 12 and 18 months). The MiniMed 780G AID system in SmartGuard Mode was used for 18 months. Parental diabetes distress was evaluated at 3 and 18 months with the validated Problem Areas in Diabetes-Parent, revised (PAID-PR) survey. RESULTS: Between 0 and 6 months, TIR and TITR increased, and HbA1c, mean SG value and TAR decreased significantly (p < 0.001); the favourable effect persisted through 18 months of follow-up. Between 3 and 18 months, PAID-PR score declined significantly (0 months: mean score 37.5; 3 months: mean score 28.6 [p = 0.06]; 18 months: mean score 24.6 [p < 0.001]). CONCLUSIONS: Treatment with AID significantly increased TITR and TIR in young children. The positive effect of AID on glycaemic control observed after 6 months persisted throughout the 18 months of follow-up. Similarly, parental diabetes distress remained reduced during 18 months follow-up. These findings are reassuring and suggest that AID treatment improves glycaemic control and reduces parental diabetes distress in young children over an extended 18-month follow-up.

Quantification of overnight urinary gonadotropin excretion predicts imminent puberty in girls: a semi-longitudinal study.

PURPOSE: We explored the alternative of using overnight fold change in gonadotropin levels by comparing the last-night-voided (LNV) and first-morning-voided (FMV) urine concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) as a conceptual analogy to the invasive gonadotropin-releasing hormone (GnRH) stimulation test setting. METHODS: We investigated the nocturnal changes in the immunoreactivity levels of urinary gonadotropins between early and late prepubertal stages as well as between early and late pubertal stages in FMV and LNV urine samples from 30 girls, of whom those who were prepubertal were further investigated through follow-up visits within the 1-year period from the start of the study. RESULTS: ROC analysis revealed that the FMV total U-LH and FMV U-FSH concentrations at or above 0.3 IU/L and 2.5 IU/L, respectively, were excellent predictors of forthcoming onset of puberty within 1 year (100% sensitivity, 100% specificity, AUC: 1.00, and n = 10, for both). FMV total U-LH concentration at or above 0.8 IU/L represented the cut-off for clinical signs of puberty. FMV/LNV total U-LH and FMV/LNV U-FSH ratios at or below 4.11 and 1.38, respectively, were also good predictors of the onset of clinical puberty within 1 year. An overnight increase (FMV/LNV ratio) in total U-LH concentrations and in the U-LH/U-FSH ratio at or below 1.2-fold in pubertal girls was associated with the postmenarcheal pubertal stage. CONCLUSION: FMV total U-LH and U-FSH above 0.3 IU/L and 2.5 IU/L, respectively, can be used as cut-off values to predict the manifestation of the clinical signs of puberty within 1 year. FMV total U-LH concentrations 0.3-0.8 IU/L and 0.6 IU/L may represent the range and the threshold, respectively, that reflect the loosening of the central brake on the GnRH pulse generator. An overnight increase of 20% or less in total U-LH concentrations and in the U-LH/U-FSH ratio in an early pubertal girl may serve as an indicator of imminent menarche, a presumed timing of which can be unraveled by future longitudinal studies.

Sex-independent timing of the onset of central puberty revealed by nocturnal luteinizing hormone concentrations.

OBJECTIVE: We designed a longitudinal study to investigate the association between the ages of central pubertal activation and the appearance of clinical signs of puberty and determined total luteinizing hormone (LH) immunoreactivity in daytime- and nocturnal sleeptime-excreted urine samples. PATIENTS AND MEASUREMENTS: Thirty healthy volunteers (17 boys and 13 girls, aged 3.4-15.2 years and 4.3-14.3 years, respectively, at the beginning of the study) were included. Male and female subjects were followed for an average of 15 visits during 5.5 and 5.8 years on average, respectively. At each visit, subjects provided 24-h urine samples divided into nocturnal sleeptime and waketime portions according to the participant's sleep-and-wake rhythm. Total urinary LH (U-LH) concentrations were measured in duplicate by Delfia® IFMA (Wallac), which has been designed specifically to detect intact LH as well as the beta subunit and its core fragment, but not the human chorionic gonadotropin. RESULTS: The initial increases in nocturnal sleeptime total U-LH concentrations over the cutoff value of 0.7 IU/L occurred at around the same time (around 9-10 years of age) in both sexes, which could not be detected in waketime urine samples. The mean first age for the nocturnal sleeptime total U-LH concentrations to reach or surpass the cutoff was 10.7 years (range: 10.2-11.6 years) in boys and 11.8 years (range: 10.7-13.4 years) in girls, showing no statistically significant difference between the sexes (p = .15). The mean time span from the age at which sleeptime total U-LH concentration first exceeded the 0.7 IU/L level to observing pubertal stage 2 was 1.5 years in boys and 0.1 years in girls. CONCLUSIONS: Findings in our population with a limited sample size suggest that the timing of central pubertal activation is a sex-independent phenomenon, which can be observed by monitoring the nocturnal sleeptime total LH concentrations in urine. The lag time from central pubertal activation of gonadotropin secretion to the clinical onset of puberty is significantly longer in boys.

MiniMed 780G™ in 2- to 6-Year-Old Children: Safety and Clinical Outcomes After the First 12 Weeks.

Objective: The safety and impact of the advanced hybrid closed-loop (AHCL) system on glycemic outcome in 2- to 6-year-old children with type 1 diabetes and the diabetes distress of caregivers were evaluated. Research Design and Methods: This was an open-label prospective study (n = 35) with historical controls matched by treatment unit, diabetes duration, age, gender, and baseline treatment modality. The inclusion criteria were (1) type 1 diabetes diagnosis >6 months, (2) total daily dose of insulin ≥8 U/day, (3) HbA1c <10% (85 mmol/mol), and (4) capability to use insulin pump and continuous glucose monitoring. The MiniMed 780G™ AHCL in SmartGuard™ Mode was used for 12 weeks. Parental diabetes distress was evaluated with a validated Problem Areas In Diabetes-Parent, revised (PAID-PR) survey. Results: No events of diabetic ketoacidosis or severe hypoglycemia occurred. Between 0 and 12 weeks, HbA1c (mean change = -2.7 mmol/mol [standard deviation 5.7], P = 0.010), mean sensor glucose value (SG) (-0.8 mmol/L [1.0], P < 0.001), and time above range (TAR) (-8.6% [9.5], P < 0.001) decreased and time in range (TIR) (8.3% [9.3], P < 0.001) increased significantly, whereas no significant change in time below range (TBR) was observed. At the same time, PAID-PR score decreased from 37.5 (18.2) to 27.5 (14.8) (P = 0.006). Conclusions: MiniMed 780G™ AHCL is a safe system and 12-week use was associated with improvements in glycemic control in 2- to 6-year-old children with type 1 diabetes. In addition, AHCL is associated with a reduction in parental diabetes distress after 12-week use. ClinicalTrials.gov registration number: NCT04949022.

The negative impact of levothyroxine treatment on urinary luteinizing hormone measurements in pediatric patients with thyroid disease.

Objectives: Previous studies suggest urinary luteinizing hormone (LH) and follicle-stimulating hormone (FSH) measurements by immunofluorometric assays (IFMA) as noninvasive alternatives to serum assays for puberty assessment. However, these studies excluded patients with other endocrine disorders and those taking medications. Besides, the recent discontinuation of IFMA manufacturing is a concern. We explored the utility of luminometric assays (LIA) for urinary gonadotropins and thyroid-stimulating hormone (TSH) determinations in euthyroid patients with thyroid pathologies. Methods: We used LIA and IFMA assays to measure serum and first-morning-voided (FMV) urine LH, FSH, and TSH concentrations in euthyroid patients with various thyroid disorders. Of the 47 euthyroid patients with normal serum TSH (S-TSH) levels, 14 were receiving levothyroxine therapy. Results: FMV total urinary LH (U-LH) concentrations correlated significantly with those measured in serum using either LIA (r=0.67, P<.001) or IFMA (r=0.83, P=.003) in patients not receiving levothyroxine treatment; however, no significant correlation could be detected in patients receiving levothyroxine regardless of the assay method (for LIA: r=0.50, P=.08 and IFMA r=0.44, P=.15). Urinary TSH (U-TSH) concentrations correlated poorly with those in serum in both the untreated and the treated groups (r=-0.13, P=.49, and r=-0.45, P=.11, respectively). Conclusion: FMV total U-LH determinations by LIA can be used to assess pubertal development in patients with thyroid pathology, provided the euthyroid patient is not on levothyroxine treatment. U-TSH measurements by LIA cannot replace invasive S-TSH measurements at least in patients with normal S-TSH levels. Further research may reveal the utility of U-TSH determinations in patients with elevated S-TSH levels.

Health-related quality of life in boys with constitutional delay of growth and puberty.

Introduction: Constitutional delay of growth and puberty (CDGP) is the most common reason for delayed puberty in healthy male adolescents. The main indication for medical treatment for this condition is psychosocial burden. However, to the best of our knowledge, no previous study has addressed the impact of puberty-promoting treatment on health-related quality of life (HRQoL) among boys with CDGP. Methods: We investigated HRQoL in 22 boys with CDGP, who participated in a randomized controlled trial in four Finnish pediatric endocrinology outpatient clinics between 2013 and 2017. The boys were randomized to receive either aromatase inhibitor letrozole (2.5mg/day; n=11) or intramuscular testosterone (1mg/kg/every 4 weeks; n=11) for 6 months and followed up to 12 months. HRQoL was assessed with a generic self-assessment 16D© instrument developed and validated for adolescents aged 12 to 15 years. The 16D includes 16 dimensions (vitality, sight, breathing, distress, hearing, sleeping, eating, discomfort and symptoms, speech, physical appearance, school and hobbies, mobility, friends, mental function, excretion and depression). The results were compared with an age-matched reference population that included 163 boys from the Finnish capital-city area. The study protocol is registered to ClinicalTrials.gov (registration number: NCT01797718). Results: At baseline, the mean 16D score of the CDGP boys was similar to the age-matched reference population (0.95 vs 0.96, p=0.838). However, the physical appearance score (satisfaction with general appearance, height and weight) was significantly lower in the CDGP boys (0.75 vs 0.92, p=0.004) than their peers. Twelve months after treatment, Appearance had improved significantly (0.75 vs 0.87, p=0.004) and no HRQoL dimension was inferior compared to the age-matched reference population. Discussion: In terms of HRQoL, the main impact of delayed puberty was dissatisfaction with physical appearance. Puberty promoting therapy was associated with a positive change in perceived appearance, with no clear difference between low-dose testosterone and letrozole treatments.

Quantification of urinary total luteinizing hormone immunoreactivity may improve the prediction of ovulation time.

Objectives: Most of the currently available ovulation prediction kits provide a relatively rough estimation of ovulation time with a short fertility window. This is due to their focus on the maximum probability of conception occurring one day before ovulation, with no follow-up after LH surge until ovulation nor during the subsequent days thereafter. Earlier studies have shown that urine of reproductive age women contains at least 3 different molecular forms of luteinizing hormone (LH); 1) intact LH, 2) LH beta-subunit (LHß) and a 3) small molecular weight fragment of LHß, LHß core fragment (LHßcf). The proportion of these LH forms in urine varies remarkably during the menstrual cycle, particularly in relation to the mid-cycle LH surge. In this exploratory study, we studied the potential implications of determining the periovulatory course of total LH immunoreactivity in urine (U-LH-ir) and intact LH immunoreactivity in serum (S-LH-ir) in the evaluation of the fertility window from a broader aspect with emphasis on the post-surge segment. Methods: We determined total U-LH-ir in addition to intact S-LH-ir, follicle-stimulating hormone (FSH), progesterone, and estradiol in 32 consecutive samples collected daily from 10 women at reproductive age. Inference to the non-intact U-LH-ir levels was made by calculating the proportion of total U-LH-ir to intact S-LH-ir. Results: Total U-LH-ir increased along with LH surge and remained at statistically significantly higher levels than those in serum for 5 consecutive days after the surge in S-LH-ir. S-LH-ir returned to follicular phase levels immediately on the following day after the LH surge, whereas the same took 7 days for total U-LH-ir. Conclusions: The current exploratory study provides preliminary evidence of the fact that U-LH-ir derived from degradation products of LH remains detectable at peak levels from the LH surge until ovulation and further during the early postovulatory period of fecundability. Thus, non-intact (or total) U-LH-ir appears to be a promising marker in the evaluation of the post-surge segment of the fertility window. Future studies are needed to unravel if this method can improve the prediction of ovulation time and higher rates of fecundability in both natural and assisted conception.

Timing of puberty and school performance: A population-based study.

Objective: To determine whether the timing of puberty associates with school performance. Methods: Growth data on 13,183 children born between 1997 and 2002, were collected from child health clinics and school healthcare and school performance data from school records. Age at peak height velocity (PHV) marked pubertal timing. The relationships between age at PHV and average grades in mathematics, native language, English, and physical education from school years 6 (end of elementary school; age 11-12 years), 7 (start of middle school; 12-13 years), and 9 (end of middle school; 14-15 years) were modeled using generalized estimating equations and linear mixed models, adjusted for the month of birth and annual income and education levels in school catchment areas. Results: The mean (SD) age at PHV was 13.54 (1.17) years in boys and 11.43 (1.18) years in girls. In girls, age at PHV was associated with grades in mathematics (ß=0.041-0.062, p<0.005) and physical education (ß=0.077-0.107, p<0.001) across the study years, and in school year 9, also with grades in English (ß=-0.047, 95%CI -0.072 to -0.021, p<0.001). Among boys, only the grades in physical education were related to age at PHV across the study years (ß=0.026-0.073, p<0.01) and in middle school the grades in mathematics decreased dramatically. Conclusions: In both sexes, the timing of puberty was associated with the grades in physical education, and in girls, with academic achievement. The decrease in boys' mathematics grades and sex difference in academic achievement were unexplained by the timing of puberty.

Presentation and diagnosis of childhood-onset combined pituitary hormone deficiency: A single center experience from over 30 years.

Background: Childhood-onset combined pituitary hormone deficiency (CPHD) has a wide spectrum of etiologies and genetic causes for congenital disease. We aimed to describe the clinical spectrum and genetic etiologies of CPHD in a single tertiary center and estimate the population-level incidence of congenital CPHD. Methods: The retrospective clinical cohort comprised 124 CPHD patients (48 with congenital CPHD) treated at the Helsinki University Hospital (HUH) Children's Hospital between 1985 and 2018. Clinical data were collected from the patient charts. Whole exome sequencing was performed in 21 patients with congenital CPHD of unknown etiology. Findings: The majority (61%;76/124) of the patients had acquired CPHD, most frequently due to craniopharyngiomas and gliomas. The estimated incidence of congenital CPHD was 1/16 000 (95%CI, 1/11 000-1/24 000). The clinical presentation of congenital CPHD in infancy included prolonged/severe neonatal hypoglycaemia, prolonged jaundice, and/or micropenis/bilateral cryptorchidism in 23 (66%) patients; despite these clinical cues, only 76% of them were referred to endocrine investigations during the first year of life. The median delay between the first violation of the growth screening rules and the initiation of GH Rx treatment among all congenital CPHD patients was 2·2 years, interquartile range 1·2-3·7 years. Seven patients harbored pathogenic variants in PROP1, SOX3, TBC1D32, OTX2, and SOX2, and one patient carried a likely pathogenic variant in SHH (c.676G>A, p.(Ala226Thr)). Interpretation: Our study suggests that congenital CPHD can occur in 1/16 000 children, and that patients frequently exhibit neonatal cues of hypopituitarism and early height growth deflection. These results need to be corroborated in future studies and might inform clinical practice. Funding: Päivikki and Sakari Sohlberg Foundation, Biomedicum Helsinki Foundation, and Emil Aaltonen Foundation research grants.

Identification of the LH surge by measuring intact and total immunoreactivity in urine for prediction of ovulation time.

OBJECTIVES: In our earlier study, we separated three different molecular forms of urinary LH-ir (U-LH-ir) by gel filtration and identified them by immunoassay in urine from regularly menstruating women on periovulatory days. U-LH-ir is composed of intact luteinizing hormone (LH), its free beta-subunit (LHß), and the core fragment of LHß (LHßcf), the latter two establishing the non-intact portion of LH-ir. The aim was to determine whether timing of ovulation can be improved by detecting different molecular forms of U-LH-ir in women of reproductive age. METHODS: We determined intact and total U-LH-ir in 14 regularly menstruating women on consecutive periovulatory days during the menstrual cycle. Non-intact LH-ir was calculated as the arithmetic difference between total and intact LH-ir. In addition, LH-ir was determined in both serum and urine from four of the women throughout the menstrual cycle. RESULTS: During the LH surge, U-LH-ir consisted mainly of intact LH and presented with an abrupt increase. Intact U-LH-ir dropped rapidly within 1 day after the surge, reaching baseline levels at the end of the luteal phase. In contrast, LHßcf in urine increased further 1 day after the surge. After this, most of the U-LH-ir consisted of LHßcf and it remained strongly elevated (over fivefold compared to intact LH) for the first 3 days after the LH surge, moderately elevated (over threefold) thereafter until day + 5, and mildly elevated until day + 7. CONCLUSIONS: Total and non-intact LH-ir are potential add-on characteristics which can be utilized in ovulation predictor kits to measure LH-ir in urine beyond the LH surge during a broader time frame, thereby paving the way for more precise prediction of the timing of ovulation than that obtained with currently available products.

Intact luteinizing hormone (LH), LHß, and LHß core fragment in urine of menstruating women.

OBJECTIVES: We examined different molecular forms of luteinizing hormone (LH) in urine samples taken during periovulatory days with the aim of revealing different forms of LH immunoreactivity (LH-ir) in normally menstruating women. METHODS: Serum and first-morning-voided urine serum samples were obtained from six healthy, 22 to 38 years old, regularly menstruating women during their periovulatory days based on their previous menstrual cycles. The day of the LH surge was determined on the basis of serum LH concentrations and confirmed by an at least two-fold increase in urinary concentrations of intact LH on consecutive days. Different molecular forms of LH-ir were identified by gel filtration of first-morning-voided urine samples obtained from regularly menstruating women on periovulatory days. RESULTS: Different forms of LH immunoreactivity (LH-ir) were distinguished as intact LH, its free beta-subunit (LHß), and the core fragment of LHß (LHßcf) according to their molecular sizes. The latter two are also called non-intact LH. Intact LH was the dominating form on the day before and on the day of LH surge while LHßcf was the major form of LH immunoreactivity after the LH surge for the following 5-7 days. LHß was detected on the day of the LH surge as well as on the following day. CONCLUSIONS: These results indicate that LH is degraded in the kidneys and excreted as LHß, and mainly as LHßcf for 7 days following the LH peak.

Circulating Liver-enriched Antimicrobial Peptide-2 Decreases During Male Puberty.

CONTEXT: Circulating levels of liver-enriched antimicrobial peptide 2 (LEAP2), a ghrelin receptor antagonist, decrease under caloric restriction and increase in obesity. The role of LEAP2 in male puberty, a phase with accelerated energy demand, is unclear. OBJECTIVE: This work aimed to investigate whether circulating LEAP2 levels are downregulated in boys following the onset of puberty to respond to the energy need required for growth. METHODS: We determined circulating LEAP2 levels in 28 boys with constitutional delay of growth and puberty (CDGP) who participated in a randomized controlled trial (NCT01797718), and were treated with letrozole (n = 15) or intramuscular low-dose testosterone (T) (n = 13) for 6 months. Blood sampling and dual-energy x-ray absorptiometry-measured body composition were performed at 0-, 6-, and 12-month visits. RESULTS: Serum LEAP2 levels decreased statistically significantly during pubertal progression (0-6 months: mean decrease -4.3 [10.3] ng/mL, P = .036 and 0-12 months: -3.9 [9.3] ng/mL, P = .033). Between 0 and 6 months, the changes in serum LEAP2 levels correlated positively with changes in percentage of body fat (rs = 0.48, P = .011), and negatively with growth velocity and estradiol levels (rs = -0.43, P = .022, rs = -0.55, P = .003, respectively). In the T group only, the changes in serum LEAP2 correlated negatively with changes in T and estradiol levels. Between 0 and 12 months, the change in LEAP2 levels correlated negatively with the change in high-density lipoprotein levels (rs = -0.44, P = .022) and positively with the change in insulin (rs = 0.50, P = .009) and HOMA-IR (rs = 0.51, P = .007) levels. CONCLUSION: Circulating LEAP2 levels decreased after induction of puberty reciprocally with increased growth rate and energy demand, reflecting the metabolic state of the adolescent. Further, the results suggest that estradiol levels may have a permissive role in downregulating circulating LEAP2 levels.

Serum testosterone and oestradiol predict the growth response during puberty promoting treatment.

OBJECTIVE: The influence of androgens and oestrogens on growth is complex, and understanding their relative roles is important for optimising the treatment of children with various disorders of growth and puberty. DESIGN: We examined the proportional roles of androgens and oestrogens in the regulation of pubertal growth in boys with constitutional delay of growth and puberty (CDGP). The study compared 6-month low-dose intramuscular testosterone treatment (1 mg/kg/month; n = 14) with per oral letrozole treatment (2.5 mg/day; n = 14) which inhibits conversion of androgens to oestrogen. PATIENTS: Boys with CDGP were recruited to a randomized, controlled, open-label trial between 2013 and 2017 (NCT01797718). MEASUREMENTS: The patients were evaluated at 0-, 3- and 6-month visits, and morning blood samples were drawn. Linear regression models were used for data analyses. RESULTS: In the testosterone group (T-group), serum testosterone concentration correlated with serum oestradiol concentration at the beginning of the study and at 3 months, whereas in the letrozole group (Lz-group) these sex steroids correlated only at baseline. Association between serum testosterone level and growth velocity differed between the T and Lz groups, as each nmol/L increase in serum testosterone increased growth velocity 2.7 times more in the former group. Serum testosterone was the best predictor of growth velocity in both treatment groups. In the Lz-group, adding serum oestradiol to the model significantly improved the growth estimate. Only the boys with serum oestradiol above 10 pmol/L had a growth velocity above 8 cm/year. CONCLUSIONS: During puberty promoting treatment with testosterone or aromatase inhibitor letrozole, growth response is tightly correlated with serum testosterone level. A threshold level of oestrogen appears to be needed for an optimal growth rate that corresponds to normal male peak height velocity of puberty. Serum testosterone 1 week after the injection and serum testosterone and oestradiol 3 months after the onset of aromatase inhibitor treatment can be used as biomarkers for treatment response in terms of growth.

Onset and progression of puberty in Klinefelter syndrome.

OBJECTIVE: Klinefelter syndrome (KS) (47,XXY and variants, KS) is the most common sex chromosome disorder in humans. However, little is known about the onset and progression of puberty in patients with KS. In this study, we describe the onset and progression of puberty in a large series of boys with KS in a single tertiary centre. DESIGN AND PATIENTS: Retrospective data (Tanner stages, testicular length, testosterone supplementation, levels of luteinizing hormone [LH] and testosterone) before possible testosterone treatment on 72 KS patients with 47,XXY karyotype were reviewed, and G (n = 59 patients) and P (n = 56 patients) stages were plotted on puberty nomograms. MEASUREMENTS AND RESULTS: One boy had a delayed onset of puberty, as he was at the G1 stage at the age of 13.8 years (-2.2 SDs). No observations of delay were made of boys at Stage G2. The progression of G stages was within normal limits in the majority of patients; only few boys were late at G3 (4.1%; 1 out of 24) and G4 (7.4%; 2 out of 27). Testosterone supplementation was started at the average age of 15.5 years to 35 boys (47%), 2 of whom were over 18 years old. LH level was on average 18.2 IU/L (SD: 6.3 IU/L) and testosterone 9.1 nmol/L (SD: 3.1 nmol/L) when testosterone supplementation was started. CONCLUSIONS: Our results suggest that puberty starts within the normal age limits in boys with KS, and testosterone supplementation is not needed for the initial pubertal progression in the majority of patients.

The aetiology of extreme tall stature in a screened Finnish paediatric population.

BACKGROUND: Extremely tall children (defined as height SDS (HSDS) ≥+3) are frequently referred to specialized healthcare for diagnostic work-up. However, no systematic studies focusing on such children currently exist. We investigated the aetiology, clinical features, and auxological clues indicative of syndromic tall stature in extremely tall children subject to population-wide growth monitoring and screening rules. METHODS: Subjects with HSDS ≥+3 after three years of age born between 1990 and 2010 were identified from the Helsinki University Hospital district growth database. We comprehensively reviewed their medical records up to December 2020 and recorded underlying diagnoses, auxological data, and clinical features. FINDINGS: We identified 424 subjects (214 girls and 210 boys) who fulfilled the inclusion criteria. Underlying growth disorder was diagnosed in 61 (14%) patients, in 36 (17%) girls and 25 (12%) boys, respectively (P=0•15). Secondary causes were diagnosed in 42 (10%) patients and the two most frequent secondary diagnoses, premature adrenarche, and central precocious puberty were more frequent in girls. Primary disorder, mainly Marfan or Sotos syndrome, was diagnosed in 19 (4%) patients. Molecular genetic studies were used as a part of diagnostic work-up in 120 subjects. However, array CGH or next-generation sequencing studies were seldom used. Idiopathic tall stature (ITS) was diagnosed in 363 (86%) subjects, and it was considered familial in two-thirds. Dysmorphic features or a neurodevelopmental disorder were recorded in 104 (29%) children with ITS. The probability of a monogenic primary growth disorder increased with the degree of tall stature and deviation from target height. INTERPRETATION: A considerable proportion of extremely tall children have an underlying primary or secondary growth disorder, and their risk is associated with auxological parameters. Clinical features related to syndromic tall stature were surprisingly frequent in subjects with ITS, supporting the view that syndromic growth disorders with mild phenotypes may be underdiagnosed in extremely tall children. Our results lend support to comprehensive diagnostic work-up of extremely tall children. FUNDING: Päivikki and Sakari Sohlberg Foundation, Foundation for Pediatric Research, and Helsinki University Hospital research grants.