FSH-stimulated Inhibin B (FSH-iB): A Novel Marker for the Accurate Prediction of Pubertal Outcome in Delayed Puberty.

BACKGROUND: Clinicians have long been struggling to find an effective tool to predict onset of puberty. OBJECTIVE: To explore stimulability of inhibin B after exogenous FSH and its potential role for prediction of onset of puberty. DESIGN AND PARTICIPANTS: Study subjects were enrolled into "exploratory cohort" (n = 42) and "validation cohort" (n = 19). The exploratory cohort was further divided into group 1 (healthy children with spontaneous puberty [SP], n = 26) and group 2 (patients with hypogonadotropic hypogonadism [HH], n = 16). The validation cohort included children who presented with complaints of delayed puberty. INTERVENTION AND OUTCOME: Participants were subjected to FSH stimulation test and GnRH analogue stimulation test. Cutoffs derived from the exploratory cohort for basal and FSH stimulated inhibin B (FSH-iB) were applied on the validation cohort. Basal LH, GnRH analogue-stimulated LH, basal inhibin B, and FSH-iB were compared with clinical outcomes on a prospective follow-up for prediction of onset of puberty. RESULTS: There was statistically significant increment in inhibin B after exogenous FSH in group 1 (SP) in both male (188.8 pg/mL; P = 0.002) and female (1065 pg/mL; P = 0.023) subjects. The increment was not statistically significant in group 2 (HH) in both sexes. FSH-iB at a cutoff of 116.14 pg/mL in males and 116.50 pg/mL in females had 100% sensitivity and specificity for labelling entry into puberty. On application of these cutoffs on the validation cohort, FSH-iB had 100% positive predictive value, negative predictive value, and diagnostic accuracy for prediction of pubertal onset. CONCLUSION: Inhibin B was stimulable in both male and female subjects. FSH-iB can be considered a novel and promising investigation for prediction of onset of puberty. Future studies are required for further validation.

Circulating miR-30b levels increase during male puberty.

OBJECTIVE: The role of miRNA as endocrine regulators is emerging, and microRNA mir-30b has been reported to repress Mkrn3. However, the expression of miR-30b during male puberty has not been studied. DESIGN AND METHODS: Circulating relative miR-30b expression was assessed in sera of 26 boys with constitutional delay of growth and puberty (CDGP), treated with low-dose testosterone (T) (n =11) or aromatase inhibitor letrozole (Lz) (n =15) for 6 months and followed up to 12 months (NCT01797718). The associations between the relative expression of miR-30b and hormonal markers of puberty were evaluated. RESULTS: During the 12 months of the study, circulating miR-30b expression increased 2.4 ± 2.5 (s.d.) fold (P = 0.008) in all boys, but this change did not correlate with corresponding changes in LH, testosterone, inhibin B, FSH, or testicular volume (P = 0.25-0.96). Lz-induced activation of the hypothalamic-pituitary-gonadal (HPG) axis was associated with more variable miR-30b responses at 3 months (P < 0.05), whereas those treated with T exhibited significant changes in relative miR-30b levels in the course the study (P < 0.01-0.05). CONCLUSIONS: Circulating miR-30b expression in boys with CDGP increases in the course of puberty, and appears to be related to the activity of the HPG axis.

Using Kisspeptin to Predict Pubertal Outcomes for Youth With Pubertal Delay.

CONTEXT: The management of youth with delayed puberty is hampered by difficulty in predicting who will eventually progress through puberty and who will fail to attain adult reproductive endocrine function. The neuropeptide kisspeptin, which stimulates gonadotropin-releasing hormone (GnRH) release, can be used to probe the integrity of the reproductive endocrine axis. OBJECTIVE: We sought to determine whether responses to kisspeptin can predict outcomes for individuals with pubertal delay. DESIGN, SETTING, AND PARTICIPANTS: We conducted a longitudinal cohort study in an academic medical center of 16 children (3 girls and 13 boys) with delayed or stalled puberty. INTERVENTION AND OUTCOME MEASURES: Children who had undergone kisspeptin- and GnRH-stimulation tests were followed every 6 months for clinical evidence of progression through puberty. Inhibin B was measured in boys. A subset of participants underwent exome sequencing. RESULTS: All participants who had responded to kisspeptin with a rise in luteinizing hormone (LH) of 0.8 mIU/mL or greater subsequently progressed through puberty (n = 8). In contrast, all participants who had exhibited LH responses to kisspeptin ≤ 0.4 mIU/mL reached age 18 years without developing physical signs of puberty (n = 8). Thus, responses to kisspeptin accurately predicted later pubertal outcomes (P = .0002). Moreover, the kisspeptin-stimulation test outperformed GnRH-stimulated LH, inhibin B, and genetic testing in predicting pubertal outcomes. CONCLUSION: The kisspeptin-stimulation can assess future reproductive endocrine potential in prepubertal children and is a promising novel tool for predicting pubertal outcomes for children with delayed puberty.

Plasma kisspeptin levels in boys with hypogonadotropic delayed puberty.

BACKGROUND: In hypogonadotropic forms of delayed puberty (DP), hypophyseal follicle-stimulating (FSH) and luteinizing (LH) hormones, normally released with GnRH stimulation, are detected low. Since kisspeptin (KP) is a strong stimulant of GnRH neurons, it is considered to have a role in DP etiology. It may be hypothesized that abnormal plasma levels of KP are indicative of DP. The study aimed at evaluation and comparison of plasma KP levels in boys of pre-pubertal age, with normal puberty and diagnosed primary hypogonadotropic forms of DP. METHODS: The study comprised 22 boys with verified hypogonadotropic DP (age 14-17 years), 25 boys with normal puberty (age 14-17 years), and 28 pre-pubertal boys (age 6-9 years). Triprorelin stimulation test was performed in DP patients. Plasma KP values were compared between three groups. RESULTS: Statistically significant difference was found for the overall distribution of the plasma KP values across different groups (Kruskal-Wallis H=21.95, P<0.001). The highest values were found in the DP group (median: 45.0 pg/mL). Median values in the pre-pubertal boys and in the normal pubertal adolescents were equal to 13.8 pg/mL. No statistically significant difference was found for plasma KP levels in the DP boys who had either positive or negative response to Triptorelin stimulation test. Plasma KP level exceeding 16.9 pg/mL was a reliable predictor of hypoganadotropic DP (sensitivity 72.7%, specificity 92.0%). CONCLUSIONS: Plasma KP levels are elevated in hypogonadotropic DP cases and may serve as a useful diagnostic tool in evaluating boys with DP.

Anti-Müllerian hormone and letrozole levels in boys with constitutional delay of growth and puberty treated with letrozole or testosterone.

STUDY QUESTION: Does treatment of constitutional delay of growth and puberty (CDGP) in boys with aromatase inhibitor letrozole (Lz) or conventional low-dose testosterone (T) have differing effects on developing seminiferous epithelium? SUMMARY ANSWER: Anti-Müllerian hormone (AMH) declined similarly in both treatment groups, and the two Sertoli cell-derived markers (AMH and inhibin B (iB)) exhibited differing responses to changes in gonadotrophin milieu. WHAT IS KNOWN ALREADY: Boys with CDGP may benefit from puberty-inducing medication. Peroral Lz activates gonadotrophin secretion, whereas intramuscular low-dose T may transiently suppress gonadotrophins and iB. STUDY DESIGN, SIZE, DURATION: Sera of 28 boys with CDGP who participated in a randomised, controlled, open-label trial at four paediatric centres in Finland between August 2013 and January 2017 were analysed. The patients were randomly assigned to receive either Lz (2.5 mg/day) (n = 15) or T (1 mg/kg/month) (n = 13) for 6 months. PARTICIPANTS/MATERIALS, SETTING, METHODS: The 28 patients were at least 14 years of age, showed first signs of puberty, wanted medical attention for CDGP and were evaluated at 0, 3, 6 and 12 months of visits. AMH levels were measured with an electrochemiluminescence immunoassay and Lz levels with liquid chromatography coupled with tandem mass spectrometry. MAIN RESULTS AND THE ROLE OF CHANCE: AMH levels decreased in both treatment groups during the 12-month follow-up (P < 0.0001). Between 0 and 3 months, the changes in gonadotrophin levels (increase in the Lz group, decrease in the T group) correlated strongly with the changes in levels of iB (FSH vs iB, r = 0.55, P = 0.002; LH vs iB, r = 0.72, P < 0.0001), but not with the changes in AMH (P = NS). At 12 months, AMH levels did not differ between the groups (P = NS). Serum Lz levels (range, 124-1262 nmol/L) were largely explained by the Lz dose per weight (at 3 months r = 0.62, P = 0.01; at 6 months r = 0.52, P = 0.05). Lz levels did not associate with changes in indices of hypothalamic-pituitary-gonadal axis activity or Sertoli cell markers (in all, P = NS). LIMITATIONS, REASONS FOR CAUTION: The original trial was not blinded for practical reasons and included a limited number of participants. WIDER IMPLICATIONS OF THE FINDINGS: In early puberty, treatment-induced gonadotrophin stimulus was unable to counteract the androgen-mediated decrease in AMH, while changes in iB levels were associated with changes in gonadotrophin levels. AMH decreased similarly in both groups during the treatment, reassuring safety of developing seminiferous epithelium in both treatment approaches. Since a fixed dose of Lz induced variable serum Lz levels with a desired puberty-promoting effect in all boys, more research is needed to aim at a minimal efficient dose per weight. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the Academy of Finland, the Foundation for Pediatric Research, the Emil Aaltonen Foundation, Sigrid Juselius Foundation and Helsinki University Hospital Research Funds. The authors have nothing to disclose. TRIAL REGISTRATION NUMBER: NCT01797718.

Letrozole versus testosterone for promotion of endogenous puberty in boys with constitutional delay of growth and puberty: a randomised controlled phase 3 trial.

BACKGROUND: The treatment of constitutional delay of growth and puberty (CDGP) is an underinvestigated area in adolescent medicine. We tested the hypothesis that peroral aromatase inhibition with letrozole is more efficacious than intramuscular injection of low-dose testosterone in inducing puberty in boys with CDGP. METHODS: We did a randomised, controlled, open-label trial at four paediatric centres in Finland. Boys aged at least 14 years with CDGP who wanted medical intervention and exhibited the first signs of puberty were randomly assigned in blocks of ten to receive either six intramuscular injections of low-dose testosterone (about 1 mg/kg bodyweight) every 4 weeks for 6 months or peroral letrozole 2·5 mg once daily for 6 months. All boys were followed up for 6 months after the end of treatment. The primary outcomes were changes in testicular volume and hormonal markers of puberty at 6 months after treatment initiation, which were assessed in all participants who received the assigned treatment. All patients were included in the safety analysis. This study is registered with ClinicalTrials.gov, number NCT01797718. FINDINGS: Between Aug 1, 2013, and Jan 30, 2017, 30 boys were randomly assigned to receive testosterone (n=15) or letrozole (n=15). One boy in the testosterone group was excluded from the primary analyses because of a protocol deviation. During treatment, boys in the letrozole group had higher serum concentrations of luteinising hormone, follicle-stimulating hormone, testosterone, and inhibin B than did boys in the testosterone group. Testicular growth from baseline to 6 months was greater in the letrozole group than in the testosterone group (7·2 mL [95% CI 5·2-9·3] vs 2·2 mL [1·4-2·9]; between-group difference per month 0·9 mL [95% CI 0·6-1·2], p<0·0001). Most adverse events were mild. One boy in the testosterone group had aggressive behaviour for 1 week after each injection, and one boy in the letrozole group had increased irritability at 6 months. INTERPRETATION: Letrozole might be a feasible alternative treatment to low-dose testosterone for boys with CDGP who opt for medical intervention. However, the risks and benefits of manipulating the reproductive axis during early puberty should be weighed carefully. FUNDING: Helsinki University Hospital, Academy of Finland, and Finnish Foundation for Pediatric Research.

Ultrasonographic assessment of pubertal breast development in obese children: compliance with the clinic.

BACKGROUND: The aim of the study was to determine the compliance with the clinical and ultrasonographic staging of pubertal breast development in obese children. METHODS: Fifty-two obese children with Tanner stage 2 and stage 3 breast development accompanied by at least one pubertal clinical finding were included in the study. The staging of breast development was also performed according to the ultrasonographic morphostructural appearance. The subjects were then divided into subgroups according to their clinical and ultrasonographic breast stages. The stages given by both methods were compared for consistency with the hormonal values and other radiological (uterus long diameter, ovary sizes) findings. RESULTS: The correlation between the clinical and ultrasonographic staging of pubertal breast development was determined to be weak (r=0.19). Estradiol levels, uterus long diameter and ovary sizes were significantly increased when the ultrasonographic stage increased among the subjects with clinically similar breast development stage. However, no statistical difference was determined in these parameters among the subjects with ultrasonographically similar but clinically different breast development. CONCLUSIONS: It was shown that the ultrasonographic staging of breast development could provide more accurate and objective data due to the possible mistakes caused in the breast development staging of obese children by their adipose tissue.

Serum relaxin-3 hormone relationship to male delayed puberty.

Puberty is the transitional period between childhood and adulthood, a process encompassing morphological, physiological and behavioural development to attain full reproductive capability. This study aimed to assess serum relaxin-3 hormone relationship with male delayed puberty. Sixty males were investigated as two equal groups: males with delayed puberty and healthy matched males as controls. They were subjected to history taking, clinical examination and estimation of serum FSH, LH, testosterone, relaxin-3 hormonal levels. The results showed that the secondary sexual characters in the patients group were at Tanner stages 1-2 and in the healthy controls at Tanner stages 3-5. The mean BMI in the patients group was significantly increased, whereas the mean levels of the span, testicular volume, serum LH, FSH, testosterone as well as relaxin-3 hormonal levels were significantly decreased compared with the healthy controls. Serum relaxin-3 levels showed significant positive correlation with the age, testis volume, span, Tanner stages, serum testosterone, FSH, LH hormones. In addition, serum relaxin-3 levels showed significant negative correlation with BMI. It is concluded that serum level of relaxin-3 hormone is an important mediator in the pathophysiological process of normal puberty being significantly decreased in males with delayed puberty.

Loss of PI3K p110α in the Adipose Tissue Results in Infertility and Delayed Puberty Onset in Male Mice.

Deletion of PI3K catalytic subunit p110α in adipose tissue (aP2-Cre/p110αflx/flx, α-/- hereafter) results in increased adiposity, glucose intolerance, and liver steatosis. Because this endocrine organ releases hormones like leptin, which are important in reproductive physiology, we investigated the reproductive phenotype of α-/- males. Compared to controls, α-/- males displayed delayed onset of puberty accompanied by a reduction in plasma LH levels and testicular weight. At postnatal day 30, α-/- mice exhibited normal body weight but elevated fasted plasma leptin levels. Testicular leptin gene expression was increased, whereas expression of the cholesterol transporter StAR and of P450 cholesterol side chain cleavage enzyme was decreased. Adult α-/- males were infertile and exhibited hyperandrogenemia with normal basal LH, FSH, and estradiol levels. However, neither sperm counts nor sperm motility was different between genotypes. The mRNA levels of leptin and of 17-beta-dehydrogenase 3, and enzyme important for testosterone production, were significantly higher in the testis of adult α-/- males. The mRNA levels of ERα, an important regulator of intratesticular steroidogenesis, were lower in the testis of adult and peripubertal α-/- males. We propose that chronic hyperleptinemia contributes to the negative impact that disrupting PI3K signaling in adipocytes has on puberty onset, steroidogenesis, and fertility in males.

Diagnostic utility of testosterone priming prior to dynamic tests to differentiate constitutional delay in puberty from isolated hypogonadotropic hypogonadism.

CONTEXT: Differentiation between constitutional delay in puberty (CDP) and isolated hypogonadotropic hypogonadism (IHH) during adolescence is a great clinical challenge, and the available diagnostic tests are of limited value. OBJECTIVE: To study the effect of withdrawal of short-term, low-dose testosterone therapy (testosterone priming) on the discriminatory power of dynamic tests for hypothalamo-pituitary-testicular axis to differentiate CDP from IHH. DESIGN: A prospective study (n = 30) consisting of 20 boys with delayed puberty (group A) and 10 patients with IHH (group B). INTERVENTION: Patients in groups A and B underwent Triptorelin and hCG stimulation tests, prior to and 2 months after withdrawal of 'testosterone priming' (100 mg intramuscularly 4 weekly for 3 months) and were followed up until the onset of puberty or 18 years of age, whichever was earlier. RESULTS: At baseline, Triptorelin-stimulated 4 h LH, with a cut-off of 2·8 IU/l, and hCG-stimulated day 7 testosterone with a cut-off of 3·8 nmol/l had sensitivities of 80% each, and specificities of 93% and 87%, respectively, to diagnose CDP. After withdrawal of testosterone, a 4 h LH cut-off of 14·7 IU/l and day 7 testosterone cut-off of 10·3 nmol/l had sensitivities of 93% and 88% respectively, and specificity and positive predictive value of 100% each. A basal inhibin B > 94·7 ng/l was discriminatory for diagnosing CDP after withdrawal of testosterone priming. CONCLUSIONS: Inhibin B levels or 4 h LH after Triptorelin stimulation are the best discriminatory tests to differentiate CDP from IHH, when performed after withdrawal of 'testosterone priming'.

Congenital hypogonadotropic hypogonadism, functional hypogonadotropism or constitutional delay of growth and puberty? An analysis of a large patient series from a single tertiary center.

STUDY QUESTION: What diagnoses underlie delayed puberty (DP) and predict its outcome? SUMMARY ANSWER: A multitude of different diagnoses underlie DP, and in boys a history of cryptorchidism, small testicular size and slow growth velocity (GV) predict its clinical course. WHAT IS KNOWN ALREADY: DP is caused by a variety of underlying etiologies. Hormonal markers can be used in the differential diagnosis of DP but none of them have shown complete diagnostic accuracy. STUDY DESIGN, SIZE, DURATION: Medical records of 589 patients evaluated for DP in a single tertiary care center between 2004 and 2014 were retrospectively reviewed. PARTICIPANTS/MATERIALS, SETTING, METHODS: Clinical and biochemical data of 174 boys and 70 girls who fulfilled the criteria of DP were included in the analyses. We characterized the frequencies of underlying conditions and evaluated the predictive efficacy of selected clinical and hormonal markers. MAIN RESULTS AND THE ROLE OF CHANCE: Thirty etiologies that underlie DP were identified. No markers of clinical value could be identified in the girls, whereas a history of cryptorchidism in the boys was associated with an increase in the risk of permanent hypogonadism (odds ratio 17.2 (95% CI; 3.4-85.4, P < 0.001)). The conditions that cause functional hypogonadotropic hypogonadism were more frequent in boys with a GV below 3 cm/yr than in those growing faster (19% vs 4%, P < 0.05). In this series, the most effective markers to discriminate the prepubertal boys with constitutional delay of growth and puberty (CDGP) from those with congenital hypogonadotropic hypogonadism (CHH) were testicular volume (cut-off 1.1 ml with a sensitivity of 100% and a specificity of 91%), GnRH-induced maximal LH (cut-off 4.3 IU/L; 100%, 75%) and basal inhibin B (INHB) level (cut-off 61 ng/L; 90%, 83%). LIMITATIONS, REASONS FOR CAUTION: The main limitation of the study is the retrospective design. WIDER IMPLICATIONS OF THE FINDINGS: Prior cryptorchidism and slow GV are two important clinical cues that may help clinicians to predict the clinical course of DP in boys, whereas markers of similar value could not be identified in girls. In prepubertal boys, testicular size appeared as effective as INHB and GnRH-induced LH levels in the differential diagnosis between CHH and CDGP. STUDY FUNDING/COMPETING INTERESTS: This study was supported by the Academy of Finland (268356), Foundation for Pediatric Research (7495), Sigrid Juselius Foundation (2613) and the Finnish Medical Foundation (011115). The authors have no competing interests to report. TRIAL REGISTRATION NUMBER: Not applicable.

Comparing effect levels of regulatory studies with endpoints derived in targeted anti-androgenic studies: example prochloraz.

Prochloraz is an imidazole fungicide, and its regulatory toxicological data package has been primarily generated in the 1990s. More recently, studies have been published demonstrating an interaction with hormone receptors/steroidogenesis and effects with an endocrine mode of action. In the present study, prochloraz has been investigated in a comprehensive in vivo study including relevant elements of current regulatory reproduction toxicity studies and additional mechanistic parameters. Prochloraz was administered per gavage in oil from GD 6 to PND 83 to pregnant and lactating Wistar rats and their respective offspring, at doses of 0.01 mg/kg bw/day (acceptable daily intake of prochloraz), 5 mg/kg bw/day [expected no-observed-effect-level (NOEL)] and 30 mg/kg bw/day. At 30 mg/kg bw/day maternal and offspring effects (decreased viability, lower number of live offspring) were seen including a delayed entry into male puberty (+1 day) accompanied by lower male offspring body weights, increased anogenital distance/index in females and transiently retained nipples in males at PND 12 (not seen at PND 20). The only finding at the "expected NOEL" was increased incidences of transiently retained nipples in males which are not considered adverse. No effects were seen in the low-dose group. There was no evidence for a non-monotonic dose-response curve or effects at low levels.

The investigation of children and adolescents with abnormalities of pubertal timing.

Concerns with pubertal development are common and can cause considerable distress to patients and their carers. Many presentations reflect normal variations of pubertal timing and primarily require reassurance, although patients may opt for interventions. Other presentations need active management to avoid significant adverse effects on growth and psychosocial development. All should undergo careful assessment, particularly as some children or adolescents presenting with abnormalities in pubertal timing may have serious pathology which requires urgent investigations and treatment. This review describes the appropriate investigations and their interpretation for young people presenting with disorders in pubertal timing.

Genetic variations altering FSH action affect circulating hormone levels as well as follicle growth in healthy peripubertal girls.

STUDY QUESTION: Do variants of the genes encoding follicle stimulating hormone (FSH) beta subunit (B) and FSH receptor (R) impact circulating reproductive hormone levels and ovarian follicle maturation in healthy peripubertal girls? SUMMARY ANSWER: FSHB and FSHR genetic variants exert, alone or their combination, distinct effects on reproductive hormone levels as well as ovarian follicle maturation in healthy peripubertal girls. WHAT IS KNOWN ALREADY: FSHB and FSHR genetic variants impact reproductive hormone levels as well as associated pathologies in women. While FSHR c. 2039A>G is known to alter gonadotrophin levels in women, FSHR c.-29G>A has not yet been shown to exert effect and there are conflicting results concerning FSHB c.-211G>T. STUDY DESIGN, SIZE, DURATION: This population-based study included 633 girls recruited as part of two cohorts, the COPENHAGEN Puberty Study (2006-2014, a cross-sectional and ongoing longitudinal study) and the Copenhagen Mother-Child Cohort (1997-2002, including transabdominal ultrasound (TAUS) of the ovaries in a subset of 91 peripubertal girls). PARTICIPANTS/MATERIALS, SETTING, METHODS: Clinical examinations, including pubertal breast stage (Tanner's classification B1-B5) were performed. Circulating levels of FSH, luteinizing hormone (LH), estradiol, anti-Mullerian hormone (AMH) and inhibin-B were assessed by immunoassays. In a subset of the girls (n = 91), ovarian volume and the number/size of antral follicles were assessed by TAUS. Genotypes were determined by competitive PCR. MAIN RESULTS AND THE ROLE OF CHANCE: FSHR c.2039A>G minor alleles were positively associated with serum FSH (ß = 0.08, P = 0.004), LH (ß = 0.06, P = 0.012) and estradiol (ß = 0.06, P = 0.017) (adjusted for Tanner stages). In a combined model, FSHR c.-29G>A and FSHR c.2039A>G alleles were positively associated with FSH levels in early-pubertal girls (B2 + B3, n = 327, r = 0.1, P = 0.02) and in young adolescents (B4 + B5, n = 149, r = 0.2, P = 0.01). Serum AMH and inhibin B levels were not significantly influenced by the single nucleotide polymorphisms (SNPs). Single SNPs were not associated with follicles counts, however, a cumulative minor allele count (FSHB c.-211 G>T and FSHR c.-29G>A) was negatively associated with the number of large follicles (≥5 mm) (n = 91, P = 0.04) (adjusted for Tanner stages). LIMITATIONS, REASONS FOR CAUTION: Since we studied girls and young adolescents during pubertal transition, our study may not be fully comparable with previous studies on FSHB and FSHR variants in adult women. The group of young adolescents (Tanner B4 + B5) reflects the endocrine situation in adult women best, however, the group is not large enough to contribute substantially to the conflicting results concerning the influence of FSHB c.-211G>T in adult women. Furthermore, we have no information about the exact day of the menstrual cycle in the subgroup of girls with menarche. WIDER IMPLICATIONS OF THE FINDINGS: The sex-specific interaction of FSHB and FSHR genetic variants and physiological as well as pathological conditions is being increasingly elucidated. The variant triplet set might serve as diagnostic and pharmacogenetic marker. For the first time, we show an additional effect of FSHR c.-29G>A on serum FSH levels in healthy girls. Moreover, morphological data suggest impaired FSH-induced maturation of ovarian follicles in minor allele carriers of FSHB c.-211G>T and FSHR c.-29G>A. This may explain previous findings of delayed pubertal onset in these girls. STUDY FUNDING/COMPETING INTERESTS: Funding was provided by the Danish Agency for Science, Technology and Innovation (09-067180), Danish Ministry of the Environment, CeHoS (MST-621-00065), Capital Region of Denmark (December 2011), Ministry of Higher Education and Science (DFF-1331-00113) and EDMaRC (Danish Ministry of Health). A.S.B. was funded from December 2015 by ReproUnion (EU Interreg Öresund-Kattegat-Skagerrak). The authors declare no conflict of interest.

Role of Gonadotropin-releasing Hormone Stimulation Test in Diagnosing Gonadotropin Deficiency in Both Males and Females with Delayed Puberty.

BACKGROUND: Delayed puberty can result either from constitutional delay of growth and puberty (CDP) or idiopathic hypogonadotropic hypogonadism (IHH). Gonadotropin-releasing hormone (GnRH) stimulation test has been generally accepted as a current method for diagnosing delayed puberty. The objective of this research was to assess the cut-off values and the efficacy of GnRH stimulation test in the diagnosis of delayed puberty in both males and females. METHODS: A study of 91 IHH, 27 CDP patients, 6 prepubertal children, and 20 pubertal adults was undertaken. Blood samples were obtained at 0, 30, 60, and 120 min after GnRH administration and the levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured. For each parameter, the sensitivities and specificities were estimated, and the receiver operating characteristic (ROC) curves were constructed. RESULTS: The ROC curves indicated that a serum basal LH <0.6 IU/L or peak LH <9.74 IU/L resulted in moderate sensitivity (73.8% or 80.0%) and specificity (90.9% or 86.4%) in the diagnosis of HH in males. Serum basal LH <0.85 IU/L or basal FSH <2.43 IU/L resulted in moderate sensitivity (80.0% or 100.0%) and specificity (75.0% or 50.0%) in the diagnosis of HH in females. CONCLUSIONS: Our data suggest that isolated use of the gonadorelin stimulation test is almost sufficient to discriminate between HH and CDP in males, but unnecessary in females. The most useful predictor is serum basal or peak LH to differentiate these two disorders in males, but serum basal LH or FSH in females.

Inhibin B, AMH, but not INSL3, IGF1 or DHEAS support differentiation between constitutional delay of growth and puberty and hypogonadotropic hypogonadism.

In pre-pubertal boys ≥ 14 years, the differentiation between constitutional delay of growth and puberty (CDGP) and hypogonadotropic hypogonadism (HH) is challenging, as current diagnostic tools have limitations in sensitivity and specificity. The aim of this study was to assess the usefulness of markers of gonadal activity, growth axis activation and adrenarche in differentiation between pre-pubertal CDGP and HH. This retrospective study was carried out between 2006 and 2015 in an academic out-patient referral centre. The clinical data of 94 boys, aged 13.9-23.2 years and referred for "pubertal delay" were reviewed. Definite diagnoses were established on initial work-up and clinical follow-up: 24 boys were diagnosed with HH, 22 boys with CDGP, pre-pubertal (PP CDGP) at referral and 28 boys with CDGP, early pubertal at referral (EP CDGP), the latter serving as control group. Twenty patients were excluded from evaluation because of previous sex steroid treatment or associated chronic disease. Inhibin B and AMH were measured in all (n = 74); INSL3, IGF1, IGFBP3 and DHEAS in a subset of patients (n = 45) in serum of first presentation. Inhibin B and AMH were higher in boys with PP CDGP than in boys with HH: inhibin B: 87.6 ± 42.5 vs. 19.8 ± 13.9 pg/mL; p < 0.001; AMH: 44.9 ± 27.1 vs. 15.4 ± 8.3 ng/mL; p < 0.001. Receiver operating characteristics (ROC) for the diagnosis of PPCDGP vs. HH (inhibin B ≥ 28.5 pg/mL): sensitivity: 95%, specificity: 75%; AUC: 0.955. In combination with an AMH cut-off ≥20 ng/mL the specificity increased to 83%. INSL3, IGF1, IGFBP3 and DHEAS levels were not different. In boys with EP CDGP, inhibin B and IGF1 levels were highest (138.7 ± 59.9 pg/mL/289.7 ± 117 ng/mL), whereas AMH levels were lowest (11.7 ± 9.1 ng/mL). Sertoli cell markers are helpful for establishing a prognosis, whether a boy with pubertal delay will enter puberty spontaneously, whereas Leydig cell, growth and adrenal markers are not.

Assessment of bone turnover markers and bone mineral density in normal short boys.

AIM: To investigate whether there is a change in bone turnover-related biochemical markers and bone mineral density of children with constitutional delay of growth and puberty (CDGP) in the prepubertal period. METHODS: We measured serum calcium, phosphorus, alkaline phosphatase, parathormone, 25-OH vitamin D, osteocalcin, osteoprotogerin and urinary deoxypyridinoline levels (D-pyd), and bone mineral density (BMD) in 31 prepubertal boys with CDGP. These children were compared with 22 prepubertal boys with familial short stature (FSS) and 27 normal prepubertal boys. RESULTS: Urinary D-pyd was significantly high in CDGP group as compared to control group (p=0.010). Volumetric BMD did not significantly differ between CDGP, FSS, and control groups (p=0.450). Volumetric BMD and urinary D-pyd levels of FSS and control groups were similar. Mean or median levels of calcium, phosphorus, alkaline phosphatase, parathormone, and osteoprotegerin did not significantly differ between CDGP, FSS, and control groups. CONCLUSIONS: Our data suggest that prepubertal boys with CDPG have normal bone turnover. However, their significantly higher urinary D-pyd levels relative to those of FSS and control groups might be an indicator of later development of osteoporosis. Therefore, long-term follow-up studies monitoring bone mineral status of prepubertal boys with CDPG from prepuberty to adulthood are needed to better understand bone metabolism of these patients.