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Objective: To describe the clinical manifestations of growth hormone (GH) excess in children with optic pathway tumors (OPT)., Study Design: Descriptive case series of 5 children with OPT, 3 with associated neurofibromatosis type 1, referred for evaluation of accelerated linear growth. GH excess was evaluated by oral glucose tolerance tests with frequent sampling of GH levels. Precocious puberty was evaluated by basal luteinizing hormone and sex steroid hormone levels. Stimulation testing with leuprolide acetate (20 μg/kg subcutaneously) was conducted in patients with normal baseline testing., Results: All patients had OPT involving both the hypothalamus and optic chiasm. All patients had elevated levels of the growth factor insulin-like growth factor 1 and on stimulation testing demonstrated an inability to suppress GH levels to < 1.0 ng/mL, indicating the presence of unregulated GH secretion. Additionally, all patients displayed biochemical evidence of precocious puberty., Conclusions: GH excess may be an under-recognized occurrence in the setting of neurofibromatosis type 1 and OPT. GH excess in such patients may contribute to continued brain tumor growth. Given the potential adverse consequences of unrestrained GH excess, all children with chiasmal or hypothalamic tumors who have rapid growth should be evaluated for both precocious puberty and GH excess., (Copyright © 2011 Mosby, Inc. All rights reserved.)

Objective: To determine whether obesity and premature adrenarche are additive events increasing the risk of insulin resistance and beta-cell failure, using early insulin response (EIR) or the insulinogenic index and proinsulin (PI) as markers., Study Design: This was a prospective case-control study conducted at a tertiary care academic medical center involving 81 prepubertal, predominantly Hispanic children (34 males, 47 females), classified as lean controls (4 males, 6 females; mean age, 6.5 +/- 1.2 years; mean body mass index [BMI] z-score, 0.08 +/- 0.6), obese controls (20 males, 10 females; mean age, 7.2 +/- 1.5 years; mean BMI z-score, 2.5 +/- 0.5), lean premature adrenarche (3 males, 11 females; mean age, 7.1 +/- 1.2 years; mean BMI z-score, 0.09 +/- 0.6), and obese premature adrenarche (7 males, 20 females; mean age, 7.3 +/- 1.0; mean BMI z-score, 2.2 +/- 0.4). Fasting glucose (G(0)), insulin (I(0)), PI(0), androgen levels, insulin-like growth factor 1, insulin-like growth factor binding protein 1, and lipid levels were obtained. An oral glucose tolerance test was performed. EIR was calculated as (I(30) - I(0))/(G(30) - G(0)). Between-group differences were assessed by 2-way analysis of variance, with interactions and associations explored with correlation/regression., Results: EIR was greater in the obese subjects with and without premature adrenarche. Combined analysis of the independent variables obesity and premature adrenarche showed that the obese premature adrenarche group had the highest EIR. The obese subjects with premature adrenarche had greater fasting PI levels than their lean counterparts. The differences in fasting PI/I ratio among the groups were not statistically significant., Conclusions: Using EIR and PI as markers to assess the risk of insulin resistance and impaired insulin secretion indicates that obese children with premature adrenarche may be at greater risk for the development of prediabetes and type 2 diabetes mellitus compared with their lean counterparts.

In boys with familial male-limited precocious puberty, an activating mutation of the luteinizing hormone receptor causes Leydig cell hyperplasia, resulting in excess testosterone production. There are no reports of Leydig cell masses in boys with familial male-limited precocious puberty. We describe a 10-year-old boy with familial male-limited precocious puberty who developed Leydig cell nodules.

The development of immunoassay techniques for accurately measuring serum gonadotropins and gonadal steroids allows distinction between central (GnRH-dependent) and peripheral (GnRH-independent) precocious puberty in children. Previously (see case 3) it was not possible to do this, and a rational approach to therapy could not be designed. Significant advances in the synthesis of superagonists of gonadotropin-releasing hormone have allowed effective treatment for children with CPP. Such treatment has only been possible for the past 10 to 15 years, and GnRHa have been approved for use in the United States for this indication only since 1992. Long-term studies are still needed to determine what effect, if any, such treatment has on fertility, because only a few patients, even from the earliest studies, have reached child-bearing age. All indications, however, suggest that treatment with GnRHa is reversible, as well as safe and efficacious. More challenging is the effective treatment of PPP, for which innovative approaches involving inhibition of gonadal steroid synthesis or action have met with some success. Again, long-term studies or efficacy and safety are needed.

A 6 5/12-year-old boy with polyostotic fibrous dysplasia, café-au-lait pigmentation of the skin, and precocious pubertal development was studied for two years. Parathormone, calcium, phosphorus, testosterone, cortisol, and growth hormone levels were within normal limits. Urinary 17-ketosteroids, 17-ketogenic steroids, and estrogens were at the upper limits of normal. After GnRH stimulation, there was only a very slight increase in LH and no increase in FSH. There was no increase in TSH after TRH, and plasma levels of T4 and T3 were normal. The plasma prolactin level was within normal limits, and increased after TRH stimulation (with a second, delayed upsurge). Abnormal distribution of 131I in the thyroid was evident, without clearcut evidence of hyperfunctioning areas after TSH stimulation and T3 suppression tests followed by conventional scanning and gamma camera scintiphotography. Our findings do not support the claimed, single, hypothalamic origin of the disease that is presumed to result in overproduction of releasing hormones; they are more in keeping with a pleiotropic, scattered peripheral lesion, possibly of embryonal origin.

Eleven girls, ages 10/12 to 76/12 years, were evaluated because of early and rapid breast development. Initial clinical presentations and serum gonadotropin or estradiol determinations did not differentiate patient types. However, patients could be divided into two groups based on their responses to synthetic gonadotropin-releasing hormone: Group A consisted of seven girls with suppressed or prepubertail-type responses, and Group B consisted of four girls with pubertal or adult-type responses. Subsequent evaluation revealed that Group A patients had intermittent or unsustained isosexual precocity, whereas Group B patients had isiopathic prococious puberty. During initial evaluation, increased serum or urinary estrogen values were noted in ten of ten patients who were studied. The greatest serum E2 values (162 and 117 pg/ml) were noted in two Group A patients; three months and two years later, those patients had normal prepubertal responses to GnRH and serum E2 values of less than 4 and 14 pg/ml, respectively. Unsustained sexual precocoity in girls may be secondary to autonomous ovarian production of estrogens, and the GnRH test may be useful in evaluation of girls with isosexual precocity.

A 7-year-old boy with sexual precocity of recent onset was found to have elevated levels of chorionic gonadotropin, alpha fetoprotein, and testosterone. Removal of a retropleural, posterior mediastinal mass with an intraspinous epidural extension was followed by prompt declines in the plasma concentrations of the tumor markers and cessation of adolescent development. The neoplasm proved to be a polyembryoma, unusual in the multiplicity of its embryoid bodies and extra gonadal location. Following local irradiation and two years of systemic chemotherapy, the patient, now 13 years of age, has done well except for evidence of testicular tubular insufficiency.