The utility of basal serum LH in prediction of central precocious puberty in girls

Reliability of self-reported pubertal development scale for girls in early adolescent: a school population-based study

OBJECTIVES

The study aimed to evaluate the correlation between self-reported pubertal developmental scale (PDS) and physically assessed Tanner staging by an experienced pediatrician among girls.

METHODS

In a school population-based study in Zhongshan, China, we recruited 1,722 girls in grades 1-3 by a multistage stratified cluster random sampling method. Participants completed self-reported PDS questionnaire prior to physical examination. Breast development was evaluated by a female pediatrician combined with ultrasound examination for overweight/obese girls; pubic hair development was evaluated. Otherwise, we tested follicle-stimulating hormone (FSH) and luteinizing hormone (LH) for some participants.

RESULTS

We observed a weak association between Tanner-derived composite stage (TDCS) and puberty category scores (PCS) (τ=0.288, p<0.001) among all girls. There was correlation (τ=0.314, p=0.001) between ultrasound-derived composite stage (UDCS) and PCS among overweight/obese girls. Moreover, among overweight/obese girls, PCS was positively correlated with LH (r=0.265, p=0.008), but not FSH (r=0.155, p=0.123), and when the basal LH value was greater than 0.3 mIU/mL, the proportion of PCS stage ≥2 (9/18) was higher than the proportion of TDCS ≥2 (5/18). As for the determination of pubertal onset, when UDCS was used as the gold standard, the specificity of PCS was 0.86 and positive predictive value was 90.00 %.

CONCLUSIONS

There was a weak correlation between PCS and TDCS among girls early adolescence. Moreover, among overweight/obese girls, combining hormone values, ultrasonographic stage of breast, and the positive predictive value of PCS, we posit that self-reported PDS might be a more reliable method than TDCS to evaluate pubertal development among overweight/obese girls.

"Management of andrological disorders from childhood and adolescence to transition age: guidelines from the Italian Society of Andrology and Sexual Medicine (SIAMS) in collaboration with the Italian Society for Pediatric Endocrinology and Diabetology (SIEDP)-Part-1"

PURPOSE

Andrological pathologies in the adulthood are often the results of conditions that originate during childhood and adolescence and sometimes even during gestation and neonatal period. Unfortunately, the reports in the literature concerning pediatric andrological diseases are scares and mainly concerning single issues. Furthermore, no shared position statement are so far available.

METHODS

The Italian Society of Andrology and Sexual Medicine (SIAMS) commissioned an expert task force involving the Italian Society of Pediatric Endocrinology and Diabetology (SIEDP) to provide an updated guideline on the diagnosis and management of andrological disorders from childhood and adolescence to transition age. Derived recommendations were based on the grading of recommendations, assessment, development, and evaluation (GRADE) system.

RESULTS

A literature search of articles in English for the term "varicoceles", "gynecomastia", "fertility preservation", "macroorchidism", "precocious puberty" and "pubertal delay" has been performed. Three major aspects for each considered disorder were assessed including diagnosis, clinical management, and treatment. Recommendations and suggestions have been provided for each of the mentioned andrological disorders.

CONCLUSIONS

These are the first guidelines based on a multidisciplinary approach that involves important societies related to the field of andrological medicine from pediatric to transition and adult ages. This fruitful discussion allowed for a general agreement on several recommendations and suggestions to be reached, which can support all stakeholders in improving andrological and general health of the transitional age.

Screening for central precocious puberty by single basal Luteinizing Hormone levels

PURPOSE

To identify cut-off for basal LH levels and for pelvic ultrasound uterine and ovarian parameters indicating an Hypotalamic-Pituitary-Gonadal (HPG) axis activation as diagnostic of Central Precocious Puberty (CPP).

METHODS

248 girls referred for suspected precocious/early puberty who had undergone a GnRH stimulation test were enrolled and divided into three groups: Premature Idiopathic Thelarche (PIT), CPP, and Early Puberty (EA). For every patient basal serum Luteinising Hormone (LH) and Follicle Stimulating Hormone (FSH), basal LH/FSH ratio and pelvic ultrasonographic parameters were also collected. Through the use of Receiver Operating Curves (ROCs) the sensitivity (Se) and specificity (Sp) of basal LH, FSH, LH/FSH ratio and ultrasonographic parameters were evaluated at each level and Area Under the Curve (AUC) was measured.

RESULTS

Basal LH model ≥0.14 mIU/mL reached the highest predictability (90.6% and 78.2%, Se and Sp, respectively). Basal LH/FSH ratio ≥0.1 showed a sensitivity of 85.90% and a specificity of 78.14%, while basal FSH cut-off (≥2.36 mIU/mL) had the lowest predictability, with a less favourable sensitivity (71%) and specificity (70.5%). Cut-off point for uterine length as 35 mm, (83.5% and 42.9% of Se and Sp, respectively) was calculated. For ovarian volumes, ROC curves showed very low sensitivity and specificity.

CONCLUSION

A single basal LH measurement under the cut-off limit may be adequate to exclude an HPG axis activation as CPP.

Girls with idiopathic central precocious puberty did not display substatial changes in body mass index after treatment with gonadotropin-releasing hormone analogues

AIM

To evaluate changes in body mass index (BMI) in girls during and after treatment for idiopathic central precocious puberty (iCPP).

METHODS

We studied 123 girls receiving gonadotropin-releasing hormone analogue (GnRHa)treatment for iCPP from 2009 to 2019. Pubertal and anthropometric measurements were monitored at routine clinical visits. BMI standard deviation scores (SDS) were estimated at baseline and followed in two stages from baseline to end of treatment (median 18.9 months) and from end of treatment to end of follow-up (median 18.2 months). The influence of baseline BMI SDS and the frequency and dose of treatment was evaluated using BMI trajectories and latent class mixed models.

RESULTS

The median age at treatment initiation was 8.5 years. The median BMI SDS at baseline was 0.7, corresponding to a median BMI of 17.4 kg/m2. Overall, no changes in BMI SDS were observed during treatment. According to baseline BMI subgroups, an increasing trend in BMI trajectories during treatment was observed for girls in the lowest BMI group. After treatment, most girls maintained stable BMI levels.

CONCLUSION

Our retrospective study did not provide evidence that GnRHa treatment for iCPP had a significant impact on BMI trajectories in girls.

Effectiveness of the triptorelin stimulation test compared with the classic gonadotropin-releasing hormone stimulation test in diagnosing central precocious puberty in girls

PURPOSE

The gonadotropin-releasing hormone (GnRH) stimulation test is the gold standard for diagnosing central precocious puberty (CPP). Gonadorelin (Relefact) is used for the test but is not always readily available; triptorelin is used as an alternative. The purpose of this study was to evaluate the diagnostic validity of the triptorelin test compared with the GnRH test in the diagnosis of CPP in girls.

METHODS

This retrospective study included 100 girls with premature thelarche (PT) who underwent a hypothalamic-pituitary-gonadal axis evaluation. In the overall group, 50 girls were tested with intravenous gonadorelin (Relefact) and 50 girls were tested with subcutaneous triptorelin acetate (Decapeptyl). Luteinizing hormone (LH) and follicle-stimulating hormone levels were measured at baseline and 30, 45, 60, and 90 minutes after gonadorelin injection or 30, 60, 90, and 120 minutes after triptorelin injection.

RESULTS

Clinical characteristics of age, height, weight, body mass index, and bone age were similar between the 2 groups. The highest LH level was reached 60 minutes after stimulation in both groups. Approximately 20% of the gonadorelin group and 24% of the triptorelin group were diagnosed with CPP (P=0.52). Among those diagnosed with CPP, the mean peak LH concentrations were 8.15 mIU/mL and 9.73 mIU/mL in the gonadorelin and triptorelin groups, respectively.

CONCLUSION

The triptorelin test showed similar trends of LH elevation and diagnostic rate compared with the traditional GnRH test for diagnosing CPP. This suggests that the triptorelin test may be a valid alternative to the GnRH test for differentiating CPP from self-limiting PT. Our study also demonstrated that a triptorelin stimulation test for up to 120 minutes was sufficient to diagnose CPP.

Peak serum luteinising hormone cut-off during gonadotropin-releasing hormone analogue test for diagnosing central precocious puberty was lower in girls with obesity as compared with girls with normal weight

OBJECTIVE

Serum luteinising hormone (LH) concentration has been reported to be lower in girls with overweight and obesity (OW/OB) as compared with girls with normal weight (NW). This study aimed to evaluate peak serum LH concentration during gonadotropin-releasing hormone analogue (GnRHa) test in girls with OW/OB and NW who had central precocious puberty (CPP) and to determine peak serum LH cut-off for diagnosing CPP in girls with OW/OB.

DESIGN, PATIENTS AND MEASUREMENTS

Medical records of 971 girls with premature breast development who underwent subcutaneous GnRHa (100 µg of triptorelin acetate) test were reviewed. All girls were classified as either CPP or premature thelarche. All of them were further classified into two groups according to their body mass index as NW and OW/OB groups for each Tanner stage.

RESULTS

There were 634 and 337 girls in NW and OW/OB groups, respectively. CPP was diagnosed in 600 girls (249 had Tanner stage II and 351 had Tanner stage III). There were no differences in peak serum LH concentrations between CPP girls with NW and OW/OB. Peak serum LH cut-off of 5 IU/L (the current widely used cut-off) had a sensitivity and a specificity of 75% and 90%, respectively in NW group. Peak serum LH cut-off for CPP diagnosis was lower at 4 IU/L in the OW/OB group with greater sensitivity and specificity of 86% and 93%, respectively. The results were reproducible for each Tanner stage of breasts.

CONCLUSION

Lower peak serum LH cut-off to 4 IU/L for diagnosing CPP in girls with OW/OB should be considered to avoid underdiagnosis of the condition.

Tall stature and gigantism in transition age: clinical and genetic aspects-a literature review and recommendations

PURPOSE

Tall stature is defined as height greater than the threshold of more than 2 standard deviations above the average population height for age, sex, and ethnicity. Many studies have described the main aspects of this condition during puberty, but an analysis of the characteristics that the physician should consider in the differential diagnosis of gigantism-tall stature secondary to a pituitary tumour-during the transition age (15-25 years) is still lacking.

METHODS

A comprehensive search of English-language original articles was conducted in the MEDLINE database (December 2021-March 2022). We selected all studies regarding epidemiology, genetic aspects, and the diagnosis of tall stature and gigantism during the transition age.

RESULTS

Generally, referrals for tall stature are not as frequent as expected because most cases are familial and are usually unreported by parents and patients to endocrinologists. For this reason, lacking such experience of tall stature, familiarity with many rarer overgrowth syndromes is essential. In the transition age, it is important but challenging to distinguish adolescents with high constitutional stature from those with gigantism. Pituitary gigantism is a rare disease in the transition age, but its systemic complications are very relevant for future health. Endocrine evaluation is crucial for identifying conditions that require hormonal treatment so that they can be treated early to improve the quality of life and prevent comorbidities of individual patient in this age range.

CONCLUSION

The aim of our review is to provide a practical clinical approach to recognise adolescents, potentially affected by gigantism, as early as possible.

Diagnostic model based on multiple factors for girls with central precocious puberty

OBJECTIVES

The GnRH stimulation test has been used as the gold standard for the diagnosis of central precocious puberty (CPP), but it has some practical barriers. This study intends to build a diagnostic model of CPP in girls based on the population in northern China.

METHODS

A total of 163 girls with precocious puberty (PP) were included from December 2018 to December 2019. Multifactor logistic regression analysis was conducted. Based on the results of multivariate logistic regression analysis, a nomogram was established for clinical application.

RESULTS

A multi logistic regression model showed that LH (OR=1.238, 95 % CI: 1.067-1.436, p=0.005), inhibin B (OR=1.066, 95 % CI: 1.032-1.100, p<0.001), bone age (OR=1.563, 95 % CI: 1.037-2.358, p=0.033), and uterine length (OR=1.180, 95 % CI: 1.034-1.348, p=0.014) were diagnostic factors for CPP. The prediction model AUC was 0.906 (95 % CI: 0.852-0.959, p<0.001).

CONCLUSIONS

We successfully developed a nomogram model for CPP patients based on clinical data. The diagnostic prediction model included four indicators: basal LH, inhibin B, bone age, and uterine body length.

Development and Validation of a Combined MRI Radiomics, Imaging and Clinical Parameter-Based Machine Learning Model for Identifying Idiopathic Central Precocious Puberty in Girls

BACKGROUND

Idiopathic central precocious puberty (ICPP) impairs child development, without early intervention. The current reference standard, the gonadotropin-releasing hormone stimulation test, is invasive which may hinder diagnosis and intervention.

PURPOSE

To develop a model for accurate diagnosis of ICPP, by integrating pituitary MRI, carpal bone age, gonadal ultrasound, and basic clinical data.

STUDY TYPE

Retrospective.

POPULATION

A total of 492 girls with PP (185 with ICPP and 307 peripheral precocious puberty [PPP]) were randomly divided by reference standard into training (75%) and internal validation (25%) data. Fifty-one subjects (16 with ICPP, 35 with PPP) provided by another hospital as external validation.

FIELD STRENGTH/SEQUENCE

T1-weighted (spin echo [SE], fast SE, cube) and T2-weighted (fast SE-fat suppression) imaging at 3.0 T or 1.5 T.

ASSESSMENT

Radiomics features were extracted from pituitary MRI after manual segmentation. Carpal bone age, ovarian, follicle and uterine volumes and endometrium presence were assessed from radiographs and gonadal ultrasound. Four machine learning methods were developed: a pituitary MRI radiomics model, an integrated image model (with pituitary MRI, gonadal ultrasound and bone age), a basic clinical model (with age and sex hormone data), and an integrated multimodal model combining all features.

STATISTICAL TESTS

Intraclass correlation coefficients were used to assess consistency of segmentation. Receiver operating characteristic (ROC) curves and the Delong tests were used to assess and compare the diagnostic performance of models. P < 0.05 was considered statistically significant.

RESULTS

The area under of the ROC curve (AUC) of the pituitary MRI radiomics model, integrated image model, basic clinical model, and integrated multimodal model in the training data was 0.668, 0.809, 0.792, and 0.860. The integrated multimodal model had higher diagnostic efficacy (AUC of 0.862 and 0.866 for internal and external validation).

CONCLUSION

The integrated multimodal model may have potential as an alternative clinical approach to diagnose ICPP.

EVIDENCE LEVEL

3.

TECHNICAL EFFICACY

Stage 2.

Central precocious puberty: a review of diagnosis, treatment, and outcomes

Central precocious puberty (CPP) refers to early activation of the hypothalamic-pituitary-gonadal (HPG) axis and is manifested by breast development in girls or testicular enlargement in boys before the normal physiological age ranges. CPP can be precipitated by intracranial pathology, exposure to high levels of sex steroids, or environmental risk factors, but most cases are idiopathic. Monogenic causes have also been identified. In this Review, we summarise pathophysiology, risk factors, diagnosis, and management of CPP. Concern for CPP should prompt referral to paediatric endocrinology where diagnosis is confirmed by clinical, biochemical, radiological, and genetic testing. CPP is treated with a gonadotropin-releasing hormone analogue, the primary aims of which are to increase adult height and postpone development of secondary sexual characteristics to an age that is more commensurate with peers. Although long-term outcomes of treatment with gonadotropin-releasing hormone analogues are reassuring, additional research on the psychological effect of CPP is needed.

Basal gonadotropin levels combine with pelvic ultrasound and pituitary volume: a machine learning diagnostic model of idiopathic central precocious puberty

OBJECTIVE

The current diagnosis of central precocious puberty (CPP) relies on the gonadotropin-releasing hormone analogue (GnRHa) stimulation test, which requires multiple invasive blood sampling procedures. The aim of this study was to construct machine learning models incorporating basal pubertal hormone levels, pituitary magnetic resonance imaging (MRI), and pelvic ultrasound parameters to predict the response of precocious girls to GnRHa stimulation test.

METHODS

This retrospective study included 455 girls diagnosed with precocious puberty who underwent transabdominal pelvic ultrasound, brain MRI examinations and GnRHa stimulation testing were retrospectively reviewed. They were randomly assigned to the training or internal validation set in an 8:2 ratio. Four machine learning classifiers were developed to identify girls with CPP, including logistic regression, random forest, light gradient boosting (LightGBM), and eXtreme gradient boosting (XGBoost). The accuracy, sensitivity, specificity, positive predictive value, negative predictive value, area under receiver operating characteristic (AUC) and F1 score of the models were measured.

RESULTS

The participates were divided into an idiopathic CPP group (n = 263) and a non-CPP group (n = 192). All machine learning classifiers used achieved good performance in distinguishing CPP group and non-CPP group, with the area under the curve (AUC) ranging from 0.72 to 0.81 in validation set. XGBoost had the highest diagnostic efficacy, with sensitivity of 0.81, specificity of 0.72, and F1 score of 0.80. Basal pubertal hormone levels (including luteinizing hormone, follicle-stimulating hormone, and estradiol), averaged ovarian volume, and several uterine parameters were predictors in the model.

CONCLUSION

The machine learning prediction model we developed has good efficacy for predicting response to GnRHa stimulation tests which could help in the diagnosis of CPP.

Precocious Puberty: Types, Pathogenesis and Updated Management

Precocious puberty (PP) means the appearance of secondary sexual characters before the age of eight years in girls and nine years in boys. Puberty is indicated in girls by the enlargement of the breasts (thelarche) in girls and in boys by the enlargement of the testes in either volume or length (testicular volume = 4 mL, testicular length = 25 mm, or both). Two types of PP are recognized - namely central PP (CPP) and peripheral PP (PPP). This paper aims to describe the clinical findings and laboratory workup of PP and to illustrate the new trends in the management of precocious sexual maturation. Gonadotropin-releasing hormone (GnRH)-independent type (PPP) refers to the development of early pubertal maturation not related to the central activation of the hypothalamic-pituitary-gonadal (HPG) axis. It is classified into genetic or acquired disorders. The most common forms of congenital or genetic causes involve McCune-Albright syndrome (MAS), familial male-limited PP, and congenital adrenal hyperplasia. The acquired causes include exogenous exposure to androgens, functioning tumors or cysts, and the pseudo-PP of profound primary hypothyroidism. On the other hand, CPP is the most common and it is a gonadotropin-dependent form. It is due to premature maturation of the HPG axis. CPP may occur as genetic alterations, such as MKRN3, DLK1, or KISS1;as a part of mutations in the epigenetic factors that regulate the HPG axis, such as Lin28b and let-7; or as a part of syndromes, central lesions such as hypothalamic hamartoma, and others. A full, detailed history and physical examination should be taken. Furthermore, several investigations should be conducted for both types of PP, including the estimation of serum gonadotropins such as luteinizing and follicle-stimulating hormones and sex steroids, in addition to a radiographic workup and thyroid function tests. Treatment depends on the type of PP: Long-acting GnRHa, either intramuscularly or implanted, is the norm of care for CPP management, while in PPP, especially in congenital adrenal hyperplasia, the goal of management is to suppress adrenal androgen secretion by glucocorticoids. In addition, anastrozole and letrozole - third-generation aromatase inhibitors - are more potent for MAS.

Clinical significance of serum MBD3 detection in girls with central precocious puberty

Diagnosis of central precocious puberty (CPP) in girls remains a huge challenge. The current study was to measure the serum expression of methyl-DNA bind protein 3 (MBD3) in CPP girls and assess its diagnostic efficacy. To begin with, we enrolled 109 CPP girls and 74 healthy pre-puberty girls. Then, MBD3 expression in their serum samples was measured via reverse transcription-quantitative polymerase chain reaction, and its diagnostic efficacy on CPP was assessed via the receiver operating characteristic (ROC) curve, followed by correlation analysis between serum MBD3 and patient age, gender, bone age, weight, height, body mass index, basal luteinizing hormone (LH), peak LH, basal follicle-stimulating hormone (FSH), peak FSH, and ovarian size using bivariate correlations method. Finally, independent predictors of MBD3 expression were confirmed using multivariate linear regression analysis. MBD3 was highly expressed in sera of CPP patients. The area under the ROC curve of MBD3 diagnosing CCP was 0.9309, with 1.475 cut-off value (92.66% sensitivity and 86.49% specificity). MBD3 expression positively correlated with basal LH, peak LH, basal FSH, and ovarian size, among which basal LH was considered the strongest independent predictor of MBD3, followed by basal FSH and peak LH. In summary, serum MBD3 could act as a biomarker in aiding CPP diagnosis.

Evaluation of Clinical and Laboratory Findings in the Differential Diagnosis of Central Precocious Puberty and Premature Thelarche

Aim

In this study, it was aimed to examine the clinical and laboratory findings that can be used to predict central precocious puberty (CPP) in cases whose breast development started before the age of 8.

Materials and Methods

The chronological age, anthropometric measurements, bone age (BA), hormone test results and pelvic ultrasonography findings of the cases were recorded. Those with a peak luteinizing hormone (LH) level of ≥5 IU/L in the gonadotropin-releasing hormone (GnRH) stimulation test were classified as CPP and those with a peak LH level of <5 IU/L were classified as prepubertal cases. A receiver operating characteristic (ROC) analysis was performed to determine the diagnostic accuracy of laboratory variables.

Findings

A total of 297 female cases were included in the study. The age at the time of admission, height-standard deviation score (SDS), BA, the long axis of the uterus and the volumes of the right and left ovaries of the cases diagnosed with CPP were found to be significantly higher than those of the prepubertal group. The cut-off value providing the best sensitivity (99%) and specificity (99%) for the peak LH was found to be 4.55; the cut-off value providing the best sensitivity (94%) and specificity (85%) for the peak LH/follicle-stimulating hormone (FSH) ratio was found to be 0.32 and the cut-off value providing the best sensitivity (47%) and specificity (93%) for the basal LH was found to be 0.13.

Conclusion

We believe that in female cases with early breast development, a peak LH level of ≥4.55 may possibly indicate CPP and a basal LH level of <0.13 can significantly rule out CPP.

Machine Learning Approach for Prediction of the Test Results of Gonadotropin-Releasing Hormone Stimulation: Model Building and Implementation

Precocious puberty in girls is defined as the onset of pubertal changes before 8 years of age, and gonadotropin-releasing hormone (GnRH) agonist treatment is available for central precocious puberty (CPP). The gold standard for diagnosing CPP is the GnRH stimulation test. However, the GnRH stimulation test is time-consuming, costly, and requires repeated blood sampling. We aimed to develop an artificial intelligence (AI) prediction model to assist pediatric endocrinologists in decision making regarding the optimal timing to perform the GnRH stimulation test. We reviewed the medical charts of 161 girls who received the GnRH stimulation test from 1 August 2010 to 31 August 2021, and we selected 15 clinically relevant features for machine learning modeling. We chose the models with the highest area under the receiver operating characteristic curve (AUC) to integrate into our computerized physician order entry (CPOE) system. The AUC values for the CPP diagnosis prediction model (LH ≥ 5 IU/L) were 0.884 with logistic regression, 0.912 with random forest, 0.942 with LightGBM, and 0.942 with XGBoost. For the Taiwan National Health Insurance treatment coverage prediction model (LH ≥ 10 IU/L), the AUC values were 0.909, 0.941, 0.934, and 0.881, respectively. In conclusion, our AI predictive system can assist pediatric endocrinologists when they are deciding whether a girl with suspected CPP should receive a GnRH stimulation test. With proper use, this prediction model may possibly avoid unnecessary invasive blood sampling for GnRH stimulation tests.

Precocious Puberty

Precocious puberty is a common presentation to pediatricians with a significant overlap between physiology and pathology. While most girls with precocious puberty have no identifiable cause, boys are more likely to have a pathological cause. The trend of earlier onset of thelarche with slow pubertal tempo has led to a significant increase in the number of girls presenting with precocious puberty. Advanced growth, bone age, uterine maturation, and elevated LH suggest rapidly progressive puberty. The critical issues in evaluating a child presenting with precocious puberty include its confirmation, exclusion of physiological variants, identification of the cause, and determining the need for treatment. Step-wise evaluation with emphasis on clinical parameters provides cost-effective assessment. Gonadotropin-releasing hormone (GnRH) analogs remain the mainstay of treatment for central precocious puberty but should be restricted to individuals with rapidly progressive puberty and compromised final height. The management of rarer forms of peripheral precocious puberty (McCune Albright syndrome, congenital adrenal hyperplasia, and testotoxicosis) involves using experimental drugs under the guidance of specialists.

High levels of FSH before puberty are associated with increased risk of metabolic syndrome during pubertal transition

BACKGROUND

During perimenopause, the rise in serum follicle-stimulating hormone (FSH) is associated with increased adiposity, insulin resistance (IR), and metabolic syndrome (MetS). However, data for the pubertal period, which is characterized by increasing FSH levels and changing body composition, are limited.

OBJECTIVES

To investigate the relationships between FSH and anthropometric changes, IR markers, and development of MetS in the peripubertal period.

METHODS

Uppsala Longitudinal Study of Childhood Obesity (ULSCO) is an ongoing study that aims to understand the factors contributing to childhood obesity and the development of obesity-related diseases. We analysed the subset of participants who were prepubertal at the first visit (n = 95, 77 with obesity). Mean follow-up time was 3.0 ± 1.4 years.

RESULTS

Higher serum FSH levels at the first visit were associated with an increased likelihood of elevation in body mass index (BMI SDS) (p = 0.025, OR = 16.10) and having MetS (p = 0.044, OR = 4.67) at the follow-up. We observed nonlinear relationships between varying serum FSH levels and markers of adiposity and IR, especially in girls. At the first visit, when girls were prepubertal, FSH was negatively associated with BMI (β = -0.491, p = 0.005) and positively associated with sex hormone-binding globulin (SHBG) (β = 0.625, p = 0.002). With the progression of puberty, negative associations between BMI and SHBG disappeared while FSH became positively associated with HOMA-IR (β = 0.678, p = 0.025) and fasting insulin (β = 0.668, p = 0.027).

CONCLUSIONS

Higher serum FSH levels in prepubertal children were associated with an increased risk of MetS development during pubertal transition. Along with nonlinear associations between varying serum FSH levels and IR markers, our results might imply a relationship between FSH and IR of puberty.

First morning voided urinary gonadotropins in children: verification of method performance and establishment of reference intervals

OBJECTIVES

Urinary luteinizing hormone (uLH) and urinary follicle-stimulating hormone (uFSH) have been shown to be useful screening and management tools for children with central precocious puberty. However, studies on uLH and uFSH reference intervals are scarce. Therefore, we aimed to establish reference intervals for uLH and uFSH, according to age, sex, and pubertal status in apparently healthy children aged 6-11 years.

METHODS

We performed detection capability, precision, accuracy by recovery, linearity, agreement analysis, and stability testing to analyze the method performance of uLH and uFSH. The Clinical Laboratory Standards Institute's C28-A3 criteria was used to establish the reference intervals.

RESULTS

Both uLH and uFSH were stable at 4 °C for 52.6 h and 64.8 days, respectively. The total imprecision of uFSH is within the manufacturer's claim, while the total imprecision of uLH remained within tolerable bias. Both uLH and uFSH could be measured with acceptable detection capability. The recovery rates of the hormones were 87.6-98.8% and 102.8-103.4%, respectively, and therefore within acceptable limits. There were significant correlations between the serum and urine concentrations (LH: r=0.91, p<0.001; FSH: r=0.90, p<0.001). The reference intervals of uLH and uFSH were established according to age, sex, and pubertal status.

CONCLUSIONS

We established reference intervals for uLH and uFSH based on age, sex and pubertal status to provide a non-invasive clinical screening tool for precocious puberty in children aged 6-11 years.

Incidental pineal gland cyst in girls with early onset of puberty

Background

The causes of an early onset of puberty are still not clearly defined and may vary from subject to subject. In girls, even if 90% of early puberty is idiopathic, magnetic resonance imaging (MRI) of the brain is performed to exclude secondary causes of precocious puberty, in particular pathological lesions as hypothalamic tumours (hamartoma). In some cases, other intracranial lesions are considered as incidental findings. Aim of the study is evaluating the prevalence of abnormal intracranial lesions detected by brain magnetic resonance imaging MRI with particular focus on the prevalence of pineal gland cysts in the diagnostic work-up of girls with central precocious puberty (CPP) as onset before 8 years and central early puberty (CEP) as onset before 10 years.

Material and methods

MRI data of girls referred from January 2010 to December 2015 to the Pediatric Endocrinology Unit of University of Pavia for early onset of breast development were collected.

Results

We collected 123 MRI data of girls referred to the Pediatric Endocrinology Unit of University of Pavia for early onset of breast development in the study period. Out of them, 25 (20.3%) had cerebral abnormalities and 15 (12.2%) had pineal gland cysts. No significant differences were noted in auxological, ultrasound and hormonal parameters at diagnosis among girls with or without pineal cysts. Patients have been observed for at least three years after the discontinuation of therapy. None of our patients had an unfavorable evolution.

Conclusions

Although pineal cysts seem to be not involved in the onset of puberty, the relevance of the finding remains controversial. Our study wants to provide further insight into the incidence of pineal cysts in pubertal advances. Of note, pineal cysts are often asymptomatic and do not evolve over time.

Triptorelin stimulated luteinizing hormone concentrations for diagnosing central precocious puberty: study of diagnostic accuracy

PURPOSE

Gonadotropin-releasing hormone (GnRH) stimulation test is the gold standard for diagnosing central precocious puberty (CPP). However, intravenous GnRH is not always readily available. The aim of the present study was to evaluate the diagnostic accuracy of triptorelin-stimulated luteinizing hormone (LH) concentrations in the diagnosis of CPP among girls presenting with premature thelarche compared to the gold standard GnRH test.

METHODS

A prospective, case-control (CPP vs isolated premature thelarche), clinical study evaluating the diagnostic accuracy of triptorelin-stimulated LH concentrations in 60 girls with premature thelarche was performed. All girls underwent stimulation with subcutaneous triptorelin injection and intravenous GnRH in a randomized order. During the stimulation test with triptorelin, LH and FSH were measured at time 0, 30, 60, 90, 120, and 180 min after the injection. Estradiol was sampled 24 h after the injection. During the GnRH test, LH and FSH were measured at time 0, 30, 45, and 60 min. Girls with peak GnRH-stimulated LH concentrations ≥5.0 IU/L were classified as having CPP. Area under the curve (AUC) for triptorelin-stimulated LH concentrations was assessed using the receiver operating characteristic (ROC) analysis.

RESULTS

Triptorelin-stimulated LH concentrations were significantly higher in girls who had CPP according to the GnRH test (53.3%). LH peaked at 180 min after the triptorelin injection. The highest diagnostic accuracy for CPP (AUC = 0.973, sensitivity 96.9%, specificity 89.3%) at 180 min was at a LH concentration ≥3.4 IU/L. The 24 h estradiol concentration did not improve the predictive model.

CONCLUSIONS

Measuring LH concentrations 180 min after triptorelin injection with a cut-off value of ≥3.4 IU/L demonstrated a high diagnostic accuracy compared to the GnRH test. Thus, stimulation with triptorelin can be used as a reliable alternative for diagnosing CPP in girls with premature thelarche.

Development and Validation of Clinical Diagnostic Model for Girls with Central Precocious Puberty: Machine-learning Approaches

BACKGROUND

A brief gonadotropin-releasing hormone analogues (GnRHa) stimulation test which solely focused on LH 30-minute post-stimulation was considered to identify girls with central precocious puberty (CPP). However, it was tested using traditional statistical methods. With advanced computer science, we aimed to develop a machine learning-based diagnostic model that processed baseline CPP-related variables and a brief GnRHa stimulation test for CPP diagnosis.

METHODS

We recruited girls suspected of precocious puberty and underwent a GnRHa stimulation test at Children Hospital 2, Vietnam, and Cathay General Hospital, Taiwan. Clinical data, bone age measurement, and 30-min post-stimulation blood test were used to build up the predictive model. The candidate model was developed by different machine learning algorithms that were mainly evaluated by sensitivity, specificity, the area under the receiver operator characteristic curve (AUC), and F1-score in internal and external validation data to classify girls as CPP and non-CPP at different time-points (0-min, 30-min, 60-min, and 120-min post-stimulation).

RESULTS

Among the 614 girls diagnosed with PP, 524 (85.3%) had CPP. The random forest algorithm yielded the highest value of F1-score (0.976), specificity (0.893), positive predicted value (0.987), and relatively high value of AUC (0.972) that contributed to high probability to identify CPP. The performance metrics of the 30-min post-stimulation diagnostic model including sensitivity and specificity surpassed those of the 0-minute model (0-min) and were equivalent to those of the model obtained 60-min and 120-min post-stimulation. Hence, our machine learning-based model helps shorten the stimulation test to 30 minutes after GnRHa injection, in general, it requires 120 minutes for a completed GnRHa stimulation test.

CONCLUSIONS

We developed a diagnostic model based on clinical features and a single sample 30-minute post-stimulation to identify CPP in girls that can reduce distress for children caused by multiple blood samplings.

Increased Incidence of Precocious Puberty in Girls During COVID-19 Pandemic: Early Indicator of the Upcoming Childhood Metabolic Syndrome Pandemic?

To evaluate retrospectively the incidence of central precocious puberty (CPP) during the COVID 19 lockdown and comparing the data with the corresponding data from the previous 2 years. The study included 23 girls with CPP and 14 patients with early puberty. Nineteen patients were newly diagnosed with CPP compared to 4 patients diagnosed with CPP during the previous 2 years. The number of new patients diagnosed with CPP was significantly higher than the mean during the previous 2 years ( P < .001). There were more overweight patients with CPP during and after the lockdown ( P < .05). These patients had also increased uterus length ( P < .05) and more advanced bone age ( P < .05). The increase in the incidence of central precocious puberty during and after the lockdown due to COVID 19 can be considered a serious consequence of the increased fat mass and an early indicator of the worsening of childhood obesity.

A Comparison of Patients with Central Precocious Puberty Who Have a Pubertal versus Prepubertal Ultrasensitive LH at Presentation

BACKGROUND

A random ultrasensitive luteinizing hormone (LH) (LH-ICMA) ≥0.3 mIU/L is highly accurate in confirming a diagnosis of central precocious puberty (CPP). However, a prepubertal value does not exclude the diagnosis. The clinical differences between patients with CPP who have a pubertal versus prepubertal LH-ICMA have not been clearly defined. Furthermore, there is minimal information regarding the utility of this test in boys with CPP. The objective of this study was to analyze differences between patients diagnosed with CPP who had a pubertal versus prepubertal LH-ICMA, including a cohort of boys.

METHODS

A retrospective chart review of children diagnosed with CPP within the last 10 years who had a baseline LH-ICMA obtained was performed. Variables analyzed included sex, age, ethnicity, bone age, BMI, etiology, Tanner stage (TS), testicular volume, and menarchal status.

RESULTS

Of 27 boys and 126 girls who qualified for the study, the LH-ICMA was pubertal in 87% and prepubertal in 13%. Girls with a pubertal LH-ICMA had higher baseline estradiol concentrations (p < 0.001) and more advanced breast development (p = 0.015) compared to girls with a prepubertal LH-ICMA. Of girls with a prepubertal LH-ICMA, 74% had at least TS 3 breast development and 1 was post-menarchal. The LH-ICMA was pubertal in 96% of the boys with CPP in this study.

CONCLUSIONS

The LH-ICMA can be prepubertal even in girls with advanced development. To our knowledge, ours is the largest cohort of boys in whom the accuracy of a random LH-ICMA has been reported.

Interpretation of reproductive hormones before, during and after the pubertal transition-Identifying health and disordered puberty

Puberty is a process of transition from childhood to adult reproductive capacity, governed by the reactivation of the hypothalamic-pituitary-gonadal axis after a long period of dormancy in mid-childhood. As such, the reproductive hormones are in a state of flux during the adolescent years, and interpretation of both the onset of healthy, concordant puberty and the differentiation of precocious, delayed or disordered puberty, can be challenging. This review is focused on the description of the endocrine axes in healthy puberty and the markers of disorders of puberty that can aid diagnosis and management for patients with these conditions. It will cover the hypothalamic, pituitary and gonadal hormone systems, the dynamic changes that occur during puberty, conditions leading to precocious, delayed or absent puberty and other syndromes with disordered puberty, and the biochemical diagnosis of these different disorders of puberty.

Role of Body Weight in the Onset and the Progression of Idiopathic Premature Pubarche

BACKGROUND

The term premature pubarche (PP) refers to the appearance of pubic hair before age 8 in girls and before age 9 in boys. Although idiopathic PP (often associated with premature adrenarche) is considered an extreme variation from the norm, it may be an initial sign of persistent hyperandrogenism. Factors contributing to PP onset and progression have not been identified to date.

AIMS

The objectives of this study are to describe a group of Italian children with PP, to identify potential factors for its onset, and to define its clinical and biochemical progression.

METHODS

We retrospectively enrolled all infants born between 2001 and 2014 with PP. Children with advanced bone age (BA) underwent functional tests to determine the cause of PP. Hormonal analysis and BA determination were performed annually during a 4-year follow-up period.

RESULTS

A total of 334 children with PP were identified: idiopathic PP (92.5%, associated with premature adrenarche in some cases); related to precocious puberty (6.6%); late-onset 21-hydroxylase deficiency (0.9%). Low birth weight was associated with premature adrenal activation. Body mass index (BMI) was the only factor that influenced the progression of BA during follow-up.

CONCLUSIONS

Low birth weight is a predisposing factor for premature adrenal activation. The increase in BMI in patients with idiopathic PP during the 4-years of follow-up was responsible for BA acceleration. We recommend prevention of excessive weight gain in children with PP and strict adherence to follow-up in order to prevent serious metabolic consequences.

The utility of serum inhibin B, anti-Müllerian hormone and insulin growth factor-1 in predicting a positive response to GnRH analogs for diagnosing central precocious puberty in girls

OBJECTIVES

The use of inhibin B (INHB), anti-Müllerian hormone (AMH) and insulin-like growth factor-1 (IGF-1) in differentiating central precocious puberty (CPP) from non-CPP was evaluated.

METHODS

In total, 115 Chinese girls were recruited (CPP: 44, non-CPP: 71). The diagnostic performance of INHB, AMH and IGF-1 in differentiating CPP from non-CPP was analyzed using receiver operating characteristic (ROC) curves.

RESULTS

INHB levels were higher in the CPP group than in the non-CPP group (55.56 ± 22.42 vs. 32.97 ± 15.59 pg/mL; p<0.001). AMH levels were similar in the CPP and non-CPP groups (6.63 ± 3.74 vs. 5.70 ± 3.15 pg/mL; p=0.158), and IGF-1 levels were much higher in the CPP group than in the non-CPP group (290.75 ± 79.78 vs. 200.10 ± 54.01 pg/mL; p<0.001). The area under the ROC curve (AUC) was greatest for INHB (0.819, standard error (SE) 0.041), followed by IGF-1 (0.809, SE 0.047) and AMH (0.567, SE 0.057). Among the ROC curves including combinations of these parameters, the AUC for INHB + IGF-1 was 0.849 and that for INHB + AMH was 0.768.

CONCLUSIONS

Serum INHB and IGF-1 measurements could predict positive responses to gonadotropin-releasing hormone (GnRH) analog stimulation in girls with precocious puberty.

The Use of Morning Urinary Gonadotropins and Sex Hormones in the Management of Early Puberty in Chinese Girls

CONTEXT

Although gonadotropin-releasing hormone stimulation test (GnRHST) is the gold standard in diagnosing central precocious puberty (CPP), it is invasive, expensive, and time-consuming, requiring multiple blood samples to measure gonadotropin levels.

OBJECTIVE

We evaluated whether urinary hormones could be potential biomarkers for prepuberty or postpuberty, aiming to simplify the current diagnosis and prognosis procedure.

METHODS

We performed a cross-sectional study of a total of 355 girls with CPP in National Clinical Research Center for Child Health in China, including 258 girls with positive and 97 girls with negative results from GnRHST. Twenty patients received GnRH analogue (GnRHa) treatment and completed a 6-month follow up. We measured luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, prolactin, progesterone, testosterone, and human chorionic gonadotropin in the first morning voided urine samples.

RESULTS

Their urinary LH levels and the ratios of LH to FSH increased significantly with the advancement in Tanner stages. uLH levels were positively associated with basal and peak LH levels in the serum after GnRH stimulation. A cutoff value of 1.74 IU/L for uLH reached a sensitivity of 69.4% and a specificity of 75.3% in predicting a positive GnRHST result. For the combined threshold (uLH ≥ 1.74 + uLH-to-uFSH ratio > 0.4), the specificity reached 86.6%. After 3 months of GnRHa therapy, the uLH and uFSH levels decreased accordingly.

CONCLUSION

uLH could be a reliable biomarker for initial CPP diagnosis and screening; uLH could also be an effective marker for evaluating the efficacy of clinical treatment.

Diagnosis and management of precocious sexual maturation: an updated review

The classic definition of precocious sexual maturation is the development of secondary sexual characteristics before 8 years of age in girls and before 9 years of age in boys. It is classified as central precocious puberty when premature maturation of the hypothalamic-pituitary-gonadal axis occurs, and as peripheral precocious puberty when there is excessive secretion of sex hormones, independent of gonadotropin secretion. Precocious sexual maturation is more common in girls, generally central precocious puberty of idiopathic origin. In boys, it tends to be linked to central nervous system abnormalities. Clinical evaluation should include a detailed history and physical examination, including anthropometric measurements, calculation of growth velocity, and evaluation of secondary sexual characteristics. The main sign to suspect the onset of puberty is breast tissue development (thelarche) in girls and testicular enlargement (≥4 mL) in boys. Hormonal assessment and imaging are required for diagnosis and identification of the etiology. Genetic testing should be considered if there is a family history of precocious puberty or other clinical features suggestive of a genetic syndrome. Long-acting gonadotropin-releasing hormone analogs are the standard of care for central precocious puberty management, while peripheral precocious puberty management depends on the etiology.Conclusion: The aim of this review is to address the epidemiology, etiology, clinical assessment, and management of precocious sexual maturation. What is Known: • The main sign to suspect the onset of puberty is breast tissue development (thelarche) in girls and testicular enlargement (≥4 mL) in boys. The classic definition of precocious sexual maturation is the development of secondary sexual characteristics before 8 years of age in girls and before 9 years of age in boys. • Long-acting gonadotropin-releasing hormone agonist (GnRHa) is the standard of care for CPP management, and adequate hormone suppression results in the stabilization of pubertal progression, a decline in growth velocity, and a decrease in bone age advancement. What is New: • Most cases of precocious sexual maturation are gonadotropin-dependent and currently assumed to be idiopathic, but mutations in genes involved in pubertal development have been identified, such as MKRN3 and DLK1. • A different preparation of long-acting GnRHa is now available: 6-month subcutaneous injection.

[Clinical guidelines «Precocious puberty»]

The precocious puberty is an urgent problem of pediatric endocrinology characterized by clinical and pathogenetic heterogeneity. The appearance of secondary sex characteristics before the age of 8 years in girls and 9 years in boys requires timely diagnosis and the appointment of pathogenetically justified treatment in order to achieve the target indicators of final growth and prevent social deprivation. The developed clinical guidelines are the main working tool of the practitioner. They briefly and structurally present the main information about the epidemiology and modern classification of рrecocious puberty, methods of its diagnosis and treatment based on the principles of evidence-based medicine.

Clinical risk score for central precocious puberty among girls with precocious pubertal development: a cross sectional study

BACKGROUND

The gold standard for the diagnosis of central precocious puberty (CPP) is gonadotropin-releasing hormone (GnRH) or GnRH analogs (GnRHa) stimulation test. But the stimulation test is time-consuming and costly. Our objective was to develop a risk score model readily adoptable by clinicians and patients.

METHODS

A cross-sectional study based on the electronic medical record system was conducted in the Children's Hospital, Fudan University, Shanghai, China from January 2010 to August 2016. Patients with precocious puberty were randomly split into the training (n = 314) and validation (n = 313) sample. In the training sample, variables associated with CPP (P < 0.2) in univariate analyses were introduced in a multivariable logistic regression model. Prediction model was selected using a forward stepwise analysis. A risk score model was built with the scaled coefficients of the model and tested in the validation sample.

RESULTS

CPP was diagnosed in 54.8% (172/314) and 55.0% (172/313) of patients in the training and validation sample, respectively. The CPP risk score model included age at the onset of puberty, basal luteinizing hormone (LH) concentration, largest ovarian volume, and uterine volume. The C-index was 0.85 (95% CI: 0.81-0.89) and 0.86 (95% CI: 0.82-0.90) in the training and the validation sample, respectively. Two cut-off points were selected to delimitate a low- (< 10 points), median- (10-19 points), and high-risk (≥ 20 points) group.

CONCLUSIONS

A risk score model for the risk of CPP had a moderate predictive performance, which offers the advantage of helping evaluate the requirement for further diagnostic tests (GnRH or GnRHa stimulation test).

Central Precocious Puberty in Boys and Girls: Similarities and Differences

Central precocious puberty (CPP) is due to the premature activation of the hypothalamic–pituitary–gonadal axis, which is responsible for the appearance of secondary sexual characteristics. It occurs before the age of 8 and 9 in girls and boys, respectively. CPP shows higher incidence in females than in males. Causes of CPP are similar in both sexes, but the idiopathic form is more frequent in girls, while organic forms are more frequent in males. Recent studies demonstrated a role of some genetic variants in the pathogenesis of CPP. The diagnostic evaluation based on accurate physical examination, assessment of the pituitary–gonadal axis, pelvic sonography in girls, and determination of bone age. Magnetic resonance of the central nervous system should be done in all boys and selected girls. Since the 1980s, pharmacologic treatment involves the use of gonadotropin-releasing hormone (GnRH) analogs. These drugs are characterized by few side effects and long-term safety. Many data are available on the outcome of GnRH analog treated female patients, while poor data are reported in boys. Adult height is improved in both sexes.

Diagnostic evaluation of central precocious puberty in girls

BACKGROUND

The gonadotropin-releasing hormone (GnRH) stimulation test is the gold standard for confirming the activation of the hypothalamic-pituitary-gonadal axis in central precocious puberty (CPP). However, it is time-consuming and costly. Our aim was to search for a simpler diagnostic modality for CPP by 1) evaluating the performance of basal serum luteinizing hormone (LH), 2) constructing a practical scoring system, and 3) determining the optimal single sampling time for serum LH in the GnRH stimulation test.

METHODS

Data of girls aged between 3 and 9 years at the time of the GnRH stimulation test, who attended our endocrine clinic at the MacKay Children's Hospital for signs of puberty between July 2014 and June 2019, were analyzed retrospectively. We recorded patients' age, height, weight, breast Tanner stage (BS), bone age, serum LH, and follicle-stimulating hormone (FSH). Receiver operating characteristic (ROC) curves and the Youden index were used to obtain the optimal basal serum LH level. Binary logistic regression was employed to construct a practical scoring system. Cross-sectional, cumulative frequency, and ROC curves were used to simplify the GnRH stimulation test.

RESULTS

Overall, 381 sets of GnRH stimulation tests were performed in 313 patients. Basal serum LH ≥ 0.2 IU/L demonstrated 70% sensitivity and 70% specificity for predicting positive GnRH stimulation test results. The practical scoring system (3 × BS + 3 × LH + 4 × FSH) showed 76% sensitivity and 72% specificity. The serum LH level at 30 min after intravenous gonadorelin exhibited 99% sensitivity and 100% specificity.

CONCLUSION

Single sampling of serum LH at 30th minute post-injection of GnRH demonstrated a diagnostic performance equivalent to the traditional GnRH stimulation test in diagnosing CPP. Therefore, this approach could become the simplest diagnostic modality.

Clinical data and basal gonadotropins in the diagnosis of central precocious puberty in girls

OBJECTIVE

The objective of this study was to analyze whether some auxological characteristics or a single basal gonadotropin measurement will be sufficient to distinguish the prepubertal from pubertal status.

METHODS

Auxologycal characteristics were recorded and serum LH and FSH were measured by immunochemiluminescence assays before and after GnRH stimulation test in a sample of 241 Caucasian girls with breast budding between 6- and 8-years old. Peak LH levels higher than 5 IU/L were considered a pubertal response. Area under the curve, cut-off points, sensitivity, and specificity for auxologycal variables and basal gonadotropins levels were determined by receiver operating curves.

RESULTS

There were no significant differences in age at onset, weight, height, BMI and height velocity between both groups. Bone age was significantly higher in pubertal girls (P < 0.05), although with limited discriminatory capacity. The sensitivity and specificity for the basal LH levels were 89 and 82%, respectively, for a cut off point of 0.1 IU/L. All girls in the pubertal group had a basal LH higher than 1.0 IU/L (positive predictive value of 100%). There was a wide overlap of basal FSH and LH/FSH ratio between prepubertal and pubertal girls.

CONCLUSIONS

Auxologycal characteristics should not be used only in the differential diagnosis between prepubertal from pubertal status in 6- to 8-year-old girls. We found a high specificity of a single basal LH sample and it would be useful for establishing the diagnosis of puberty in this age group, reducing the need for GnRH stimulation testing.

Effectiveness of basal LH in monitoring central precocious puberty treatment in girls

OBJECTIVES

Treatment of central precocious puberty (CPP) is based on administration of GnRH agonists in order to suppress hypothalamic-pituitary-gonadal axis and thus induce the stabilization or regression of pubertal development. Our aim was to determine whether the single basal serum LH and/or FSH concentration could be an effective tool to assess the efficacy of treatment to suppress activation of hypothalamic-pituitary axis.

PATIENTS AND METHODS

Serum LH and FSH were measured before and after the GnRH injection, as well as E2 basal levels in 60 girls with documented idiopathic CPP at diagnosis and 18 and 30 months after the beginning of therapy.

RESULTS

At diagnosis, peaks of >5 IU/L of LH and of FSH were observed in 100 and 91.6% of girls, respectively, with basal LH values of <1 IU/L in 70% and basal FSH levels of <1 IU/L in 10%. E2 were <20 pg/mL in 36.6%. After 18 months, a suppressed peak (i.e. <3 IU/L) was recorded in 85% of girls (p<0.01) for LH and in 98.3% for FSH (p<0.01). Basal LH <1 IU/L was detected in 85% (p<0.01) and basal FSH ≤1 IU/L in 40% (p<0.01). Serum E2 ≤20 pg/mL was recorded in 61.6% (p<0.01). After 30 months, all patients showed LH suppressed peak (p<0.01) and 98.3% suppressed FSH peak (p<0.01). 100% showed basal LH concentrations <1 IU/L (p<0.01) and 38.3% FSH basal values <1 UI/mL (p<0.01). E2 ≤20 pg/mL was observed in 32.72% (p=NS).

CONCLUSIONS

Basal LH values are a reliable indicator of the efficacy of GnRHa therapy after 30 months of GnRHa therapy.

Multiple Endocrine Deficiencies are Common in Hypoparathyroidism-Retardation-Dysmorphism Syndrome

CONTEXT

The rare hypoparathyroidism-retardation-dysmorphism (HRD) syndrome (OMIM #241410) is caused by the mutated tubulin chaperone E (TBCE) gene. This gene encodes a critical protein in the microtubule assembly pathway.

OBJECTIVE

To evaluate the endocrine profile of patients with HRD.

METHODS

The study used a retrospective analysis of a large cohort of patients in a single university medical center. Sixty-three patients were diagnosed with HRD during 1990 to 2019; 58 of them had an endocrine evaluation.

MAIN OUTCOME MEASURES

We investigated somatic growth parameters, the prevalence of hypoglycemia, growth hormone deficiency, hypothyroidism, hypogonadism, and cortisol deficiency.

RESULTS

All patients were born small for gestational age, and severe growth retardation was found in all patients with mean height standard deviation score (SDS) of -8.8 (range: -5.1 to -15.1) and weight SDS -18 (range: -5.1 to -61.2). Serum insulin-like growth factor-1 concentrations were very low among the 21 studied patients: -2.32 SDS (range: -0.6 to -2.7). Four out of 14 (28%) investigated patients had growth hormone deficiency, and 55% of patients were hospitalized due to symptomatic hypoglycemia. Adrenal glucocorticoid insufficiency was diagnosed in 22% of those tested. Hypothyroidism was found in 36% of patients. Both hypogonadotrophic and hypergonadotrophic hypogonadism were observed. The main magnetic resonance imaging findings were small anterior pituitary gland, small hippocampus, brain atrophy, thin corpus callosum, Chiari type I malformation, and septo-optic dysplasia.

CONCLUSION

Multiple endocrine abnormalities are common in patients with HRD syndrome. Periodic screening of thyroid and adrenal functions is recommended.

Gonadotropin-releasing hormone stimulation test and diagnostic cutoff in precocious puberty: a mini review

The gonadotropin-releasing hormone (GnRH) stimulation test is a valuable tool in diagnosing and differentiating causes of early pubertal occurrences. Utility of the test can be limited in some instances, however, including the early phases of pubertal hypothalamic-pituitary-gonadal axis activation, in girls showing commonly overlapping pictures, and in obese children due to excess circulating estrogen that suppresses luteinizing hormone (LH). A lack of consistent baseline and stimulated gonadotropin cutoffs observed in different studies also contributes to limitations in testing. Nevertheless, early detection of true pathological causes for pubertal disorders is needed to allow prompt treatment and better prognosis. While basal LH can be beneficial as a good screening tool for detecting pubertal disorder, it does not preclude the need for GnRH testing. The aim of this review was to highlight the role of GnRH stimulation tests and varying testing cutoffs in diagnosis of precocious puberty and its classification.

Adequacy of basal luteinizing hormone levels in the diagnosis of central precocious puberty

AIM

To determine the clinical, anthropometric, and laboratory parameters that could be used for differentiating central precocious puberty from premature thelarche in girls who had breast development between the ages of 3 and 8 years.

MATERIAL AND METHODS

The study included 344 girls (196 girls with idiopathic central precocious puberty, 148 girls with premature thelarche) who underwent gonadotropin- releasing hormone stimulation tests for breast development. Age at diagnosis, bone age, anthropometric measurements, basal/stimulated hormone levels were recorded. Univariate regression analysis was performed to determine the parameters that could be used for differentiating precocious puberty from premature thelarche. Significant parameters in univariate analyses were grouped according to the thresholds determined using receiver operating characteristic curves and reevaluated through multivariate analysis.

RESULTS

The bone age, height-standard deviation score, body mass index-standard deviation score, and growth velocity-standard deviation score at diagnosis were found to be higher; pubertal stages were found to be more advanced; uterus and ovary volumes were found to be larger; and the basal/peak luteinizing hormone, follicle-stimulating hormone, luteinizing hormone/follicle-stimulating hormone levels were found to be higher in the subjects with precocious puberty. There was no difference between estradiol levels between the two groups. The best thresholds to differentiate the two groups were found as 0.65 IU/L (78% sensitivity, 100% specificity), 1.9 IU/L (100% sensitivity, 72% specificity), 0.25 (67% sensitivity, 100% specificity) and 1.1 (69% sensitivity, 71% specificity), respectively, for basal luteinizing hormone, follicle-stimulating hormone, luteinizing hormone/follicle-stimulating hormone ratio, and the growth velocity-standard deviation score.

CONCLUSION

In girls presenting with early breast development, a basal luteinizing hormone level of ≥0.65 IU/L and a luteinizing hormone/follicle-stimulating hormone ratio of ≥0.25 are sensitive ways to demonstrate activation of the hypothalamo-pituitary-gonadal axis. Among these, the variable that gives the best sensitivity and specificity is the measurement of basal luteinizing hormone levels (≥0.65 IU/L), which can be used as a screening test in the diagnosis of central precocious puberty.

Utility and duration of leuprolide stimulation testing in children

Objective Basal (unstimulated) LH levels and leuprolide stimulation tests are used to define pubertal status of children presenting with signs of early puberty. The primary aims of this study were to (i) confirm utility of detectable basal LH levels in precluding the need for leuprolide stimulation testing, and, (ii) determine whether duration of testing could be abbreviated from usual 3 h test without compromising sensitivity. Methods We reviewed morning basal and leuprolide-stimulated LH levels in 105 children, aged 1-9 years (mean 6.9 years, SD 1.8) who were seen for concerns of precocious puberty and received a leuprolide stimulation test between June 2006 and March 2017. Results A pubertal basal LH level had high specificity and poor sensitivity for the following outcome measures: (1) peak stimulated LH≥5 mIU/mL (2) treatment with GnRHa; and (3) a composite outcome of (1) and/or (2). Following leuprolide stimulation, LH response was highest at 180 min in most children (n=78, 74.3%). Using a single cutoff of LH≥5 mIU/mL at any timepoint, 25% of children would have been misdiagnosed with an abbreviated 60 min test. A single sample at 180 min would have correctly identified 97% of patients. Conclusions A pubertal basal LH level is sufficient to distinguish children with precocious puberty without stimulation testing. However, prepubertal basal LH had relatively poor negative predictive value to refute CPP, necessitating clinical follow-up and/or a leuprolide stimulation test. For a cutoff of LH≥5 mIU/mL at any timepoint, test duration of 180 min maximizes sensitivity.

An Alport syndrome boy with Van Wyk-Grumbach syndrome induced by prolonged untreated congenital hypothyroidism

Alport syndrome (AS) is a rare genetic disorder that causes progressive nephritis and is more common among males. Studies have reported an association between thyroid antibodies and hypothyroidism in patients with AS, but the relevance of this relationship is under debate. Prolonged untreated hypothyroidism induces short stature, abnormal pubertal development, and various other symptoms. However, children with long-standing hypothyroidism rarely present with signs of precocious puberty, or Van Wyk-Grumbach syndrome (VWGS). We report the case of a boy, 8 years and 4 months old, who had VWGS caused by prolonged untreated congenital hypothyroidism and AS. The boy had repeated gross hematuria and proteinuria and was diagnosed with AS by renal biopsy and genetic testing. He had normal renal function but severe growth retardation and hypothyroidism. Obesity, bone age delay, hyperlipidemia, and abnormal increased testicle size were also present due to prolonged untreated hypothyroidism. His thyroid antibody titer elevation was unclear, although ultrasonography and thyroid scanning showed a decrease in thyroid volume. We diagnosed the patient with congenital hypothyroidism caused by thyroid dysgenesis. VWGS was diagnosed due to hypothyroidism, delayed bone age, and pseudoprecocious puberty. To the best of our knowledge, this is the first report of a prepubertal Korean boy with prolonged untreated congenital hypothyroidism complicated by VWGS in AS.

Rapid progressive central precocious puberty: diagnostic and predictive value of basal sex hormone levels and pelvic ultrasound

Objectives Data on the predictive values of parameters included in the diagnostic work-up for precocious puberty (PP) remain limited. We detected the diagnostic value of basal sex hormone levels, pelvic ultrasound parameters and bone age assessment for activation of the hypothalamic-pituitary-gonadal axis in girls with PP, in order to help in the decision to perform GnRH testing. Patients and methods We retrospectively considered 177 girls with PP. According to puberty evolution, the girls were divided into two groups: rapid progressive central precocious puberty (RP-CPP) and non/slowly progressive/transient forms (SP-PP). In all patients we considered Tanner stage, basal luteinizing hormone (LH) and estradiol (E2) values, bone age, and pelvis examination. We assessed the diagnostic value of each variable and identified the number of pathological parameters that best identify patients with RP-CPP. Results Basal LH ≥ 0.2IU/L, E2 level ≥ 50 pmol/L, uterine longitudinal diameter ≥ 3.5 cm, transverse uterine diameter ≥ 1.5 cm, endometrial echo and ovarian volume ≥ 2 cm3 were significantly associated with RP-CPP (p ≤ 0.01). The ability to diagnose RP-CPP was enhanced with increasing number of pathological hormonal and instrumental parameters (p < 0.001). With more than three parameters detected, sensitivity and specificity reached 58% (95%CI 48-67) and 85% (95%CI 74-92), respectively, with a PPV = 86% (95%CI 76-93) and PPN = 54% (95%CI 43-54); the area under the ROC curve was 0.71 (95%CI 0.65-0.78). Conclusion Despite the availability of different tests, diagnosing RP-CPP remains difficult. A diagnosis model including at least three hormonal and/or ultrasound parameters may serve as a useful preliminary step in selecting patients who require GnRH testing for early detection of RC-PP.

Use of Gonadotropin-Releasing Hormone Analogs in Children: Update by an International Consortium

This update, written by authors designated by multiple pediatric endocrinology societies (see List of Participating Societies) from around the globe, concisely addresses topics related to changes in GnRHa usage in children and adolescents over the last decade. Topics related to the use of GnRHa in precocious puberty include diagnostic criteria, globally available formulations, considerations of benefit of treatment, monitoring of therapy, adverse events, and long-term outcome data. Additional sections review use in transgender individuals and other pediatric endocrine related conditions. Although there have been many significant changes in GnRHa usage, there is a definite paucity of evidence-based publications to support them. Therefore, this paper is explicitly not intended to evaluate what is recommended in terms of the best use of GnRHa, based on evidence and expert opinion, but rather to describe how these drugs are used, irrespective of any qualitative evaluation. Thus, this paper should be considered a narrative review on GnRHa utilization in precocious puberty and other clinical situations. These changes are reviewed not only to point out deficiencies in the literature but also to stimulate future studies and publications in this area.

Basal serum luteinising hormone cut-off, and its utility and cost-effectiveness for aiding the diagnosis of the onset of puberty in girls with early stages of breast development

OBJECTIVE

To determine basal and gonadotrophin-releasing hormone analogue (GnRHa)-stimulated peak luteinising hormone (LH) cut-offs to diagnose onset of early or normal puberty in girls with each Tanner stage of breast (II and III).

DESIGN, PATIENTS AND MEASUREMENTS

A retrospective study of 601 girls with breast onset before 8 years of age who underwent GnRHa test was conducted. Patients were categorized as CPP and premature thelarche. Each group was divided into two subgroups; Tanner II and III. Cost-effectiveness analysis was performed.

RESULTS

In comparison with basal LH cut-off of 0.3 IU/L, basal LH cut-off of 0.2 IU/L had comparable specificity (Tanner II: 98.0% vs 94.8%, Tanner III: 98.8% vs 93.8%), but greater sensitivity (Tanner II: 28.3% vs 41.7%, Tanner III: 45.2% vs 59.3%). Specificity of basal LH cut-off of 0.2 IU/L was not inferior to that of the traditionally used peak LH of 5 IU/L. Using basal LH cut-off of 0.2 IU/L followed by GnRHa test in girls with negative basal LH was more cost-saving when compared with using the cut-off of 0.3 IU/L. Moreover, using basal LH cut-off of 0.2 IU/L followed by GnRHa test provided a cost reduction when compared with performing GnRHa test in all patients.

CONCLUSIONS

Basal serum LH cut-off of 0.2 IU/L could be a simple and cost-saving tool for initial diagnosis of onset of early or normal puberty in girls with Tanner II and III before proceeding to GnRH testing.

Near final adult height, and body mass index in overweight/obese and normal-weight children with idiopathic central precocious puberty and treated with gonadotropin-releasing hormone analogs

Background The standard treatment of central precocious puberty (CPP) is gonadotropin-releasing hormone analogues (GnRHa). It is a concern that children treated with GnRHa are at risk of developing obesity which could impair the treatment outcomes. This study aimed to investigate the effect of GnRHa on body mass index (BMI) standard deviation score (SDS), and the influence of BMI status on treatment outcomes in children with idiopathic CPP (iCPP). Methods A retrospective cohort study in children with iCPP who completed GnRHa treatment and had attained near final adult height (NFAH) was conducted. Children with a history of disease or drug ingestion which could affect their BMI were excluded. BMI, BMI SDS, height (Ht), Ht SDS, predicted adult height (PAH), and NFAH were compared at baseline, 1 and 2 years during treatment, and at NFAH according to the baseline BMI status; normal weight and overweight/obesity. Results Fifty-eight children with iCPP treated with GnRHa were enrolled. The BMI SDS was significantly increased at 1 and 2 years during treatment in the overweight/obese group and at 1 year during treatment in the normal-weight group. However, at NFAH (2 years after treatment discontinuation), the BMI SDS was not statistically different from baseline in both groups. Ht gain, change in Ht SDS and BMI SDS were not statistically different from the baseline in both groups. Conclusions GnRHa results in a transient increase in BMI SDS during treatment and returned to baseline after treatment cessation. The benefit of GnRHa treatment on final Ht improvement is similar between overweight/obese and normal-weight patients.

Dynamic Testing for Evaluation of Adrenal and Gonadal Function in Pediatric and Adult Endocrinology: An Overview

Dynamic tests are often considered as the backbone of endocrinology. These tests involve the use of an exogenous agent to manipulate the body's hormonal milieu for the diagnosis and characterization of an endocrine disorder. They are especially helpful in the evaluation of certain endocrine conditions, such as disorders of growth and pubertal maturation and disorders of sex development. A great deal of heterogeneity exists across clinicians with regard to the usage, methodology, and interpretation of these tests. This review outlines various dynamic tests used to evaluate adrenal and gonadal function in pediatric and adult endocrinology, along with their clinical application and interpretation.

Basal serum luteinizing hormone value as the screening biomarker in female central precocious puberty

PURPOSE

Precocious puberty refers to the development of secondary sex characteristics before ages 8 and 9 years in girls and boys, respectively. Central precocious puberty (CPP) is caused by premature activation of the hypothalamus-pituitary-gonadal (HPG) axis and causes thelarche in girls before the age of 8. A gonadotropin-releasing hormone (GnRH) stimulation test is the standard diagnostic modality for diagnosing CPP. However, the test cannot always be used for screening because it is expensive and time-consuming. This study aimed to find alternative reliable screening parameters to identify HPG axis activation in girls &lt;8 years old (CPP) and for girls 8-9 years old (early puberty, EP).

METHODS

From January 2013 to June 2015, medical records from 196 girls younger than 9 years old with onset of breast development were reviewed, including 126 girls who had a bone age (BA) 1 year above their chronological age. All patients underwent a GnRH stimulation test, and 117 underwent pelvic sonography. The girls were divided into 4 groups based on age and whether the GnRH stimulation test showed evidence of central puberty. Subanalyses were also conducted within each group based on peak luteinizing hormone (LH) level quartiles.

RESULTS

Basal serum LH level was the most sensitive marker for screening CPP and EP. The cutoff values were 0.245 IU/L for CPP under 8 years old (P=0.049, area under the curve [AUC]=0.764, 88% sensitivity, 48% specificity) and 0.275 IU/L for EP between 8-9 years old (P=0.005, AUC=0.813, 79% sensitivity, 77% specificity). Peak LH level decreased as BMI z-score among subgroups increased when there was no difference in BA; however, higher BA eliminated this effect.

CONCLUSION

Basal serum LH level is a useful screening parameter for diagnosing CPP and EP in girls. Peak LH levels were lower with increasing BMI z-score, although older BA eliminated this effect.

Central precocious puberty, functional and tumor-related

Precocious puberty is defined as the appearance of secondary sex characteristics before 8 years of age in girls and before 9 years of age in boys. Central precocious puberty (CPP) is diagnosed when activation of the hypothalamic-pituitary axis is identified. It is a rare disease with a clear female predominance. A background of international adoption increases its risk, with other environmental factors such as endocrine disruptors also being associated with CPP. The causes of CPP are heterogeneous, with alterations of the CNS being of special interest. Physical injuries of the CNS are more frequent in boys, while idiopathic etiology is more prevalent among girls. However, in the last decade the number of idiopathic cases has diminished thanks to the discovery of mutations in different genes, including KISS1, KISS1R, MKRN3, and DLK1 that cause CPP. For the diagnosis of CPP, hormone studies are needed in addition to the clinical data regarding signs of pubertal onset. For this purpose, the GnRH test continues to be the gold standard. Imaging analyses, such as bone age and brain MRI, are also very useful. Furthermore, genetic testing must be incorporated in the diagnosis of CPP, especially in familial cases. Early puberty has been related to various consequences in the medium and long term such as behavioral problems, breast cancer, obesity, and metabolic comorbidities. However, there are few studies that have exclusively analyzed patients with CPP. GnRH analogs are the most frequent treatment election with the main objective being to improve adult height. Currently, there are new formulations that are being investigated.

Morning basal luteinizing hormone, a good screening tool for diagnosing central precocious puberty

PURPOSE

The standard method used to diagnose central precocious puberty (CPP) is the gonadotropin releasing hormone stimulation test (GnRHST). However, this test is inconvenient for children because it is time-consuming and requires multiple samples. This study aimed to determine the reliability of morning unstimulated luteinizing hormone (mLH) level when screening for CPP, with an emphasis on the influence of diurnal variation.

METHODS

This study included 160 girls with signs of early puberty (SMR 2) under 8 years of age. They were classified as CPP or non-CPP based on their standard GnRHST. The auxological, biochemical, and hormonal characteristics of subjects were retrospectively evaluated. The prognostic value of single morning unstimulated gonadotropin level was examined for use in CPP screening.

RESULTS

Of 160 patients, 121 (75.6%) presented with CPP, and 39 (24.4%) were determined to be prepubertal. The mLH/mFSH (morning unstimulated follicular stimulating hormone) ratio showed significant differences between the 2 groups (P&lt;0.001). The mLH was correlated with GnRHST variables (r=0.532, P&lt;0.001). The mLH cutoff point when screening for CPP was 0.22 IU/L, which had sensitivity and specificity of 69.4% and 82.1%, respectively. In regression analysis, bone age (BA) (odds ratio [OR], 1.018; 95% confidence interval [CI], 0.967-1.071; P=0.506) and body mass index (BMI) (OR, 0.874; 95% CI, 0.583-1.310; P=0.515) were not significant predictors. The mLH≥0.22 IU/L group (OR, 9.596; 95% CI, 3.853-23.900; P&lt;0.001) was highly suggestive of CPP.

CONCLUSION

In this study, single morning unstimulated luteinizing hormone had clinical efficacy for CPP screening, but BA advanced over chronological age and BMI was not useful for CPP screening.

Central precocious puberty in girls: Diagnostic study and auxological response to triptorelin treatment

INTRODUCTION

There are several controversies regarding the diagnostic tests and management of central precocious puberty (CPP). The aim of this study is to present the experience acquired in a group of girls with CPP treated with triptorelin, and to analyze the auxological characteristics and diagnostic tests.

MATERIAL AND METHODS

An observational, retrospective study in a group of 60 girls with CPP was conducted between January 2010 and December 2017. Sociodemographic, auxological and hormonal data were recorded at diagnosis, and pelvic ultrasound and magnetic resonance imaging of the head were performed. Girls were treated with triptorelin and monitored after treatment discontinuation until menarche.

RESULTS

At treatment start, chronological age and bone age were 7.7±0.7 and 9.7±0.8 years respectively, and growth velocity was 8.3±1.6cm/year. Target height was 161.1±5.8cm. Peak LH level after stimulation was 16.6±12.1 IU/l. Ovarian volumes were greater than 3mL in 35% of cases. MRI of the head was pathological in seven girls (11.7%). At treatment completion, chronological age and bone age were 10.3±1.1 and 11.2±0.8 years respectively, and growth velocity was 4.7±1.4cm/year. At the age of menarche (11.9±0.9 years), height was 157.5±5.7cm.

CONCLUSIONS

Treatment of CPP with triptorelin appears to be beneficial. The possibility to block pubertal development and slow skeletal maturation allows patients to reach their target height. However, individualized auxological monitoring would be mandatory.

Development of Prediction Models Using Machine Learning Algorithms for Girls with Suspected Central Precocious Puberty: Retrospective Study

Background

Central precocious puberty (CPP) in girls seriously affects their physical and mental development in childhood. The method of diagnosis—gonadotropin-releasing hormone (GnRH)–stimulation test or GnRH analogue (GnRHa)–stimulation test—is expensive and makes patients uncomfortable due to the need for repeated blood sampling.

Objective

We aimed to combine multiple CPP–related features and construct machine learning models to predict response to the GnRHa-stimulation test.

Methods

In this retrospective study, we analyzed clinical and laboratory data of 1757 girls who underwent a GnRHa test in order to develop XGBoost and random forest classifiers for prediction of response to the GnRHa test. The local interpretable model-agnostic explanations (LIME) algorithm was used with the black-box classifiers to increase their interpretability. We measured sensitivity, specificity, and area under receiver operating characteristic (AUC) of the models.

Results

Both the XGBoost and random forest models achieved good performance in distinguishing between positive and negative responses, with the AUC ranging from 0.88 to 0.90, sensitivity ranging from 77.91% to 77.94%, and specificity ranging from 84.32% to 87.66%. Basal serum luteinizing hormone, follicle-stimulating hormone, and insulin-like growth factor-I levels were found to be the three most important factors. In the interpretable models of LIME, the abovementioned variables made high contributions to the prediction probability.

Conclusions

The prediction models we developed can help diagnose CPP and may be used as a prescreening tool before the GnRHa-stimulation test.

Evaluation of basal sex hormone levels for activation of the hypothalamic-pituitary-gonadal axis

BACKGROUND

This study aimed to identify the predictive value of basal sex hormone levels for activation of the hypothalamic-pituitary-gonadal (HPG) axis in girls.

METHODS

Gonadotropin-releasing hormone (GnRH) stimulation tests were performed and evaluated in a total of 1750 girls with development of secondary sex characteristics. Correlation analyses were conducted between basal sex hormones and peak luteinizing hormone (LH) levels ≥5 IU/L during the GnRH stimulation test. Receiver operating characteristic (ROC) curves for basal levels of LH, follicle-stimulating hormone (FSH), LH/FSH, and estradiol (E2) before the GnRH stimulation test were plotted. The area under the curve (AUC) and 95% confidence intervals (CIs) were measured for each curve.

RESULTS

The maximum AUC value was observed for basal LH levels (0.77, 95% CI: 0.74-0.79), followed by basal FSH levels (0.73, 95% CI: 0.70-0.75), the basal LH/FSH ratio (0.68, 95% CI: 0.65-0.71), and basal E2 levels (0.61, 95% CI: 0.59-0.64). The appropriate cutoff value of basal LH levels associated with a positive response of the GnRH stimulation test was 0.35 IU/L, with a sensitivity of 63.96% and specificity of 76.3% from the ROC curves when Youden's index showed the maximum value. When 100% of patients had peak LH levels ≥5 IU/L, basal LH values were >2.72 IU/L, but the specificity was only 5.45%.

CONCLUSIONS

Increased basal LH levels are a significant predictor of a positive response during the GnRH stimulation test for assessing activation of the HPG axis in most girls with early pubertal signs.