Evaluation of GnRH analogue testing in diagnosis and management of children with pubertal disorders

A Short-Duration Gonadotropin-Releasing Hormone Stimulation Test for the Diagnosis of Central Precocious Puberty

Background and Objectives: The gonadotropin-releasing hormone (GnRH) stimulation test is the gold standard method for diagnosing central precocious puberty (CPP), although it requires multiple blood samplings over 120 min. This study aimed to evaluate if a shorter test may have an equivalent diagnostic accuracy. Materials and Methods: We retrospectively reviewed the GnRH tests of 188 consecutive pediatric patients (169 females) referred for signs of early pubertal development. The diagnostic accuracy of the hormonal levels was evaluated at different time points (15, 0, 60, 90, and 120 min after the GnRH stimulus). Results: A diagnosis of CPP was made in 130 cases (69%), with 111 (85%) being female. Sensitivity and specificity ratings higher than 99% for the diagnosis of CPP were achieved for LH levels ≥4.7 mU/mL at 30 and 60 min after the stimulus (area under the ROC curve (AUC) = 1), with no further increase in the diagnostic accuracy in the remaining time points. No sex differences in diagnostic accuracy were found. The LH/FSH ratio at 30 min showed a sensitivity of 94.9%, with an AUC of 0.997 and a value ≥0.76. Conclusions: A short-duration GnRH test of 60 min provided optimal results for the diagnosis of CPP. Extending the test for an extra hour is therefore unnecessary and inadvisable.

Delayed Puberty

Testicular volume ≥4 ml and appearance of breast budding are the first signs of puberty. Delayed puberty is diagnosed in the absence of thelarche by 13 y or menarche by 15 y in girls and absence of testicular enlargement by 14 y in boys. Delayed puberty can be due to hypogonadotrophic hypogonadism, hypergonadotrophic hypogonadism or eugonadotrophic eugonadism characterised by low, elevated and normal gonadotrophin levels, respectively. Constitutional Delay of Growth and Puberty (CDGP) and systemic illness should be considered before pathological causes. Assessment of sexual maturity by Tanner's staging and anthropometric assessment on growth chart is pivotal. Lack of menarche in girls with thelarche suggests structural abnormalities of reproductive tract or disorders of sexual development. Measurement of bone age helps to interpret hormone measurements and decide on timing of pubertal induction. Ultrasound assessment of abdomen gives valuable clues to pubertal onset (in girls) and possible underlying etiology. Karyotyping is mandatory in all girls with delayed puberty and short stature, and delayed menarche and boys with hypergonadotrophic hypogonadism. Gonadotrophin releasing hormone analogue stimulation test may help distinguish hypogonadotrophic hypogonadism from CDGP. Pubertal induction is done with intramuscular testosterone and oral estradiol in boys and girls, respectively. Hormone replacement is begun at low doses and slowly escalated over 2 y to mimic a physiological puberty process. Short course of testosterone for 3 to 6 mo is helpful in adolescent boys with CDGP and psychological distress. Attainment of adult sexual maturity by 18 y is mandatory to rule out disorders of hypothalamic pituitary gonadal axis.

Assessment of Gonadotropin Concentrations Stimulated by Gonadotropin-Releasing Hormone Analog by Electrochemiluminescence in Girls with Precocious Puberty and Premature Thelarche

OBJECTIVE

The aim of this study is to determine the cutoff values of gonadotropin response to gonadotropin-releasing hormone analogs (GnRHas) corresponding to the activation of the hypothalamic-pituitary-gonadal axis that could differentiate central precocious puberty (CPP) from premature thelarche (PT) and using the electrochemiluminescence assay method.

METHODS

A total of 49 girls underwent the stimulation test with an intramuscular injection of 3.75 mg leuprolide acetate. Based on the clinical and laboratory characteristics, they were divided into two groups: CPP (n = 22) and PT (n = 27). Baseline estradiol, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were collected before GnRHa administration and LH and FSH at 60 and 120 min, respectively, after GnRHa administration.

RESULTS

The girls with CPP presented an increased height Z-score, advanced bone age, and higher baseline LH, FSH, estradiol, and LH/FSH ratio in relation to PT (p < 0.001). Stimulated LH differed significantly between the two groups, and the LH cutoff values were ≥4.29 IU/L (p < 0.001) and ≥3.95 IU/L at 60 and 120 min, respectively (p < 0.001). The LH peak was found at 60 min after stimulation.

CONCLUSIONS

The GnRHa test is effective in distinguishing CPP from PT, and a single sampling, at 60 min, with LH concentrations above 4.29 may be the parameter of choice with the advantage of greater convenience and practicality.

Transformation of Peripheral Sexual Precocity to Central Sexual Precocity Following Treatment of Granulosa Cell Tumor of the Ovary

Juvenile granulosa cell tumor leading to isosexual peripheral precocious puberty is a well-known association. Here, we report a rare case of central precocious puberty secondary to granulosa cell tumor of the ovary. A five-year and five-month-old girl presented with a history of progressive enlargement of bilateral breasts and intermittent vaginal spotting, associated with growth acceleration. Elevated estradiol and suppressed serum follicle-stimulating hormone were found on investigation. Additionally, abdominal and pelvic ultrasonography was suggestive of a right ovarian mass, which proved to be a juvenile granulosa cell tumor on histopathology and immunohistochemistry, leading to a diagnosis of peripheral precocious puberty secondary to granulosa cell tumor of the ovary. One and a half years after resection of the tumor, secondary sexual characteristics progressed with regression of tumor markers, and no mass was noted on ultrasonography, leading to the suspicion of central precocious puberty. Pubertal basal luteinizing hormone (LH) and elevated triptorelin-stimulated LH confirmed the diagnosis of central precocious puberty secondary to granulosa cell tumor of the ovary.

[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.

Hypogonadism in Patients with Prader Willi Syndrome: A Narrative Review

Prader-Willi syndrome (PWS) is a multisystemic complex genetic disorder related to the lack of a functional paternal copy of chromosome 15q11-q13. Several clinical manifestations are reported, such as short stature, cognitive and behavioral disability, temperature instability, hypotonia, hypersomnia, hyperphagia, and multiple endocrine abnormalities, including growth hormone deficiency and hypogonadism. The hypogonadism in PWS is due to central and peripheral mechanisms involving the hypothalamus-pituitary-gonadal axis. The early diagnosis and management of hypogonadism in PWS are both important for physicians in order to reach a better quality of life for these patients. The aim of this study is to summarize and investigate causes and possible therapies for hypogonadism in PWS. Additional studies are further needed to clarify the role of different genes related to hypogonadism and to establish a common and evidence-based therapy.

Response of South Indian girls with central precocious puberty to gonadotrophin analogue (GnRHa) therapy - a single center experience

AIM OF THE STUDY

To describe the clinical, auxological, biochemical and radiological response to GnRH analogue in female children with central precocious puberty (CPP).

MATERIAL AND METHODS

The data on 22 female children presenting with the larche < 8 years, pubarche < 8 years or menarche < 9 years diagnosed as CPP was collected from the records over a four year period. Assessment included growth parameters, Tanners staging; bone age (BA) by Greulich and Pyle method, ultrasonography of abdomen to assess uterine length and ovarian size and z score derived; biochemical evaluation included serum luteinising hormone (LH), follicle stimulating hormone (FSH) and estradiol (E2); and MRI brain. The children were initiated on injection Leupride 0.9 mg/kg 3 monthly (body weight   30 kg received 22.5 mg). The predicted adult height (PAH) was calculated with Bayley Pinneau method.

RESULTS

Treatment was started at the mean chronological age (CA) of 6.09 ±2.1 years and continued till 8.3 ±2.4 years. MRI brain was abnormal in 4 children. Duration of treatment was 2.1 ±0.4 years. The height z scores reduced from 0.5 ±2.4 to 0.18 ±2.4 (p < 0.05). A significant reduction in tanner's stage, uterine size and ovarian volume was observed in the study period. BA/CA ratio reduced from 1.27 ±0.4 to 1.07 ±0.3. PAH z score improved from 1.47 ±1.6 to 0.2 ±2.3 (p < 0.05).

CONCLUSIONS

We observed a good clinical and radiological response to GnRHa therapy in girls with CPP and a significant improvement in PAH. Long term follow up is needed to assess the attainment of final height.

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.

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.

A Gonadotropin-Releasing Hormone (GnRH) Stimulation Test Before and After GnRH Analogue Treatment for Central Precocious Puberty: Has the GnRH Test been Adequately Simplified?

OBJECTIVE

To investigate and simplify the gonadotropin-releasing hormone (GnRH) stimulation test for assessing pubertal activation and suppression.

METHODS

The authors identified 72 girls diagnosed with central precocious puberty who were treated with a GnRH analogue (GnRHa). Patients who underwent an assessment regarding GnRHa-mediated puberty suppression had been diagnosed via the GnRH stimulation test prior to GnRHa treatment. The authors analyzed the diagnostic values of the during/before-treatment LH levels at different time points by a receiver-operating characteristic (ROC) curve.

RESULTS

Before GnRHa treatment, the mean luteinizing hormone (LH) level was higher at the 30-min test time point than at baseline or the 15, 60, 90, and 120-min points (P < 0.001). After GnRHa treatment, the LH levels were suppressed in 62 patients (86.1%) and inadequately suppressed in 10 (13.9%). The LH level was higher at the 30-min test time point than those at baseline or the 45 and 60-min level (P < 0.001). The area under the curve in a post-GnRHa treatment was greatest at 30 min.

CONCLUSIONS

The simplified GnRH test is adequate for evaluating pubertal activation (30 and/or 45-min time points of the GnRH test) and suppression (the 30-min time point).