The effect of overweight on the luteinizing hormone level after gonadorelin stimulation test in girls with idiopathic central precocious puberty

Diagnostic Value of Single LH and LH/FSH Ratio at 60-minute after GnRHa Stimulation Test for Central Precocious Puberty

OBJECTIVES

To evaluate the diagnostic value of luteinizing hormone (LH) and LH/follicle stimulating hormone (FSH) ratio at 60 min after gonadotropin-releasing hormone analogs (GnRHa) stimulation test for central precocious puberty (CPP) in girls.

METHODS

Two hundred and fifty-seven girls, aged 3 to 7.5 y, suspected of precocious puberty at authors' hospital from April 2020 through November 2023 were enrolled in the study. The blood was taken at 0, 30, 60 min after GnRHa stimulation test, and LH and LH/FSH were detected by chemiluminescence assay. The diagnostic efficacy was analysed by Mann-Whitney U test, spearman's correlation analysis and receiver operating characteristic (ROC) analysis. The proportion of obesity was analysed by Chi-square test.

RESULTS

LH and LH/FSH at different times were statistically significantly different (P <0.05) between the CPP and non-CPP groups. Spearman's correlation analysis showed that the level of LH and LH/FSH at 60 min had the strongest consistency with the peak of LH (r = 0.9988, P <0.001) and LH/FSH (r = 0.9981, P <0.001). ROC curve analysis showed that the area under the ROC curves at 60 min of LH and LH/FSH were 0.975 and 0.997 with a cut-off value of 5.70 IU/L and 0.609, respectively.

CONCLUSIONS

The peak of LH and LH/FSH in the diagnosis of CPP can be determined by LH and LH/FSH at 60 min after the triptorelin acetate is injected. This will reduce the number of blood draws required compared with the traditional stimulation test, which is more effective and acceptable for children.

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.

The clinical value of serum-related indexes in differentiating simple premature thelarche from idiopathic central precocious puberty

Objective

To explore the changes of serum-related indexes at different time points, so as to identify the critical time of converting from simple premature thelarche (PT) to idiopathic central precocious puberty (ICPP).

Methods

This is a retrospective study. The subjects of the study were 50 girls with PT who were admitted to the Children's Hospital of Hebei Province from January 2019 to September 2020. The enrolled 50 children were divided into the conversion group(n=12) and the non-conversion group(n=38) according to whether PT was converted into ICPP during follow-up. Furthermore, the levels of serum-related indexes and uterine and ovarian volumes were compared after the diagnosis of PT.

Results

The IGF-1 and IGFBP-3 levels of children in the conversion group began to change significantly from six months after the diagnosis, with statistically significant differences when compared with the levels of children at the initial diagnosis, three months and those of the non-conversion group at the same time points (p<0.05). The levels of vitamin-D, DHEA and leptin began to change significantly at nine months after the diagnosis (p<0.05). Besides, uterine and ovarian volumes in the conversion group began to increase significantly six months after the diagnosis, with statistically significant differences when compared with those in the non-conversion group (p<0.05).

Conclusion

Findings in our study suggest that regular monitoring of vitamin-D, IGF-1, IGFBP-3, DHEA and leptin levels, and uterine and ovarian volumes can predict the conversion from PT to ICPP at an early stage.

2022 Clinical practice guidelines for central precocious puberty of Korean children and adolescents

The Committee of Central Precocious Puberty of Korean Pediatrics and Adolescents of the Korean Society of Pediatric Endocrinology has newly developed evidence-based 2022 clinical practice guidelines for central precocious puberty in Korean children and adolescents. These guidelines provide the grade of recommendations, which includes both the strength of recommendations and the level of evidence. In the absence of sufficient evidence, recommendations are based on expert opinion. These guidelines have been revised and supplement the previous guidelines "Clinical Guidelines for Precocious Puberty 2011," and are drawn from a comprehensive review of the latest domestic and international research and the grade of recommendation appropriate to the domestic situation. This review summarizes the newly revised guidelines into 8 key questions and 27 recommendations and consists of 4 sections: screening, diagnosis, treatment, and long-term outcome of central precocious puberty.

An Approach to the Evaluation and Management of the Obese Child With Early Puberty

With the declining age at onset of puberty and increasing prevalence of childhood obesity, early breast development in young obese girls has become a more frequent occurrence. Here, we examine available literature to answer a series of questions regarding how obesity impacts the evaluation and management of precocious puberty. We focus on girls as the literature is more robust, but include boys where literature permits. Suggestions include: (1) Age cutoffs for evaluation of precocious puberty should not differ substantially from those used for nonobese children. Obese girls with confirmed thelarche should be evaluated for gonadotropin-dependent, central precocious puberty (CPP) to determine if further investigation or treatment is warranted. (2) Basal luteinizing hormone (LH) levels remain a recommended first-line test. However, if stimulation testing is utilized, there is a theoretical possibility that the lower peak LH responses seen in obesity could lead to a false negative result. (3) Advanced bone age (BA) is common among obese girls even without early puberty; hence its diagnostic utility is limited. (4) Obesity does not eliminate the need for magnetic resonance imaging in girls with true CPP. Age and clinical features should determine who warrants neuroimaging. (5) BA can be used to predict adult height in obese girls with CPP to inform counseling around treatment. (6) Use of gonadotropin-releasing hormone analogues (GnRHa) leads to increased adult height in obese girls. (7) Obesity should not limit GnRHa use as these agents do not worsen weight status in obese girls with CPP.

MiR-664-2 impacts pubertal development in a precocious-puberty rat model through targeting the NMDA receptor-1†

Precocious puberty (PP) commonly results from premature activation of the hypothalamic-pituitary-gonadal axis (HPGA). Gonadotropin-releasing hormone (GnRH) is the initial trigger for HPGA activation and plays an important role in puberty onset. N-methyl-D-aspartate (NMDA) can promote pulsatile GnRH secretion and accelerates puberty onset. However, the mechanism of N-methyl-D-aspartate receptors (NMDARs) in PP pathogenesis remains obscure. We found that serum GnRH, luteinizing hormone (LH), follicle-stimulating hormone (FSH), estrogen (E2) levels, hypothalamic NMDAR1, and GnRH mRNA expression peaked at the vaginal opening (VO) day. Next, the hypothalamic NMDAR1 mRNA and protein levels in rats treated with danazol, a chemical commonly effecting on the reproductive system, were significantly increased at the VO day (postnatal day 24) compared to controls, accompanied by enhanced serum GnRH, LH, FSH, and E2 levels. Further, microRNA-664-2 (miR-664-2) was selected after bioinformatics analysis and approved in primary hypothalamic neurons, which binds to the 3'-untranslated regions of NMDAR1. Consistently, the miR-664-2 expression in hypothalamus of the Danazol group was decreased compared to Vehicle. Our results suggested that attenuated miR-664-2 might participate in PP pathogenesis through enhancing the NMDAR1 signaling.