Isolated 'idiopathic' micropenis: hidden genetic defects?

Micropenis is defined as a stretched penile length of less than 2-2.5SD for age. Aetiologies include hypogonadotropic hypogonadism, testicular dysgenesis, defects in testosterone synthesis, androgen resistance [5α-reductase (5αR) deficiency or partial androgen insensitivity] and other rare causes like growth hormone GH deficiency. Often, the cause remains unknown. The aim of this study was to determine whether isolated micropenis with normal plasma testosterone could hide a molecular defect in the androgen pathway. Twenty-six boys with isolated micropenis were included in this study. All of them had 46,XY karyotype, normal luteinizing hormone and follicle-stimulating hormone and a normal plasma testosterone response to human chorionic gonadotropin testing. Androgen receptor (AR), 5αR and steroidogenic factor 1 (SF1) genes were sequenced. A mutation in the AR gene was found in two patients, and a new mutation in the SF1 gene was found in one patient who was the only one to have a low level of inhibin B (InhB). This is the first report of isolated micropenis as a revealing symptom of AR and SF1 mutations. Anti-Mullerian hormone and InhB should thus be evaluated in patients with isolated micropenis, even when plasma testosterone is in the normal range. Detection of gene mutations is helpful for diagnosis, treatment and genetic counselling for probands.

[The role of gonadal peptides in clinical investigation]. / Intérêt clinique du dosage des peptides gonadiques.

Inhibins, activins, and anti-Mullerian hormone (AMH) are gonadal dimeric peptides produced in ovaries and testes by homologous cells, granulosa cells and Sertoli cells, respectively. The production of inhibins is driven by FSH, that of AMH may indirectly depends on FSH, while it is down regulated, at least in the male, by testosterone. In the past decade, measurements of serum inhibin and AMH have provided useful tools for clinical investigation in gonadal disorders: pseudohermaphroditism, androgen insensitivity, anorchidism, gonadal dysgenesis, disorders of pubertal developpement. Inhibins, activins, and AMH are also reliable markers of gonadal tumors. They are extensively used as indexes of fertility: in the male the production of inhibin B reflects the spermatogenetic activity, in women both inhibin B and AMH levels are correlated with the number of preantral and early antral follicles and reflect the ovarian reserve of follicles available for recruitment.

French Endocrine Society Guidance on endocrine side effects of immunotherapy.

The management of cancer patients has changed due to the considerably more frequent use of immune checkpoint inhibitors (ICPIs). However, the use of ICPI has a risk of side effects, particularly endocrine toxicity. Since the indications for ICPI are constantly expanding due to their efficacy, it is important that endocrinologists and oncologists know how to look for this type of toxicity and how to treat it when it arises. In view of this, the French Endocrine Society initiated the formulation of a consensus document on ICPI-related endocrine toxicity. In this paper, we will introduce data on the general pathophysiology of endocrine toxicity, and we will then outline expert opinion focusing primarily on methods for screening, management and monitoring for endocrine side effects in patients treated by ICPI. We will then look in turn at endocrinopathies that are induced by ICPI including dysthyroidism, hypophysitis, primary adrenal insufficiency and fulminant diabetes. In each chapter, expert opinion will be given on the diagnosis, management and monitoring for each complication. These expert opinions will also discuss the methodology for categorizing these side effects in oncology using 'common terminology criteria for adverse events' (CTCAE) and the difficulties in applying this to endocrine side effects in the case of these anti-cancer therapies. This is shown in particular by certain recommendations that are used for other side effects (high-dose corticosteroids, contraindicated in ICPI for example) and that cannot be considered as appropriate in the management of endocrine toxicity, as it usually does not require ICPI withdrawal or high-dose glucocorticoid intake.

Effects of an early postnatal treatment of hypogonadotropic hypogonadism with a continuous subcutaneous infusion of recombinant follicle-stimulating hormone and luteinizing hormone.

BACKGROUND: The neonatal-midinfancy surge in pulsatile gonadotropin secretion is attributable to an increase in GnRH pulse amplitude and is associated with a rapid expansion of Leydig and Sertoli cell populations with concomitant surges in testosterone, inhibin, and anti-Mullerian hormone production as well as an increase in testicular volume. Boys with congenital hypogonadotropic hypogonadism (HH) do not activate these processes. A potential cause for azoospermia and infertility in adult life is deficient proliferation of immature Sertoli cells before and during puberty due to the absence of FSH. OBJECTIVE: The objective of the study was to investigate whether early postnatal continuous sc infusion of gonadotropins could mimic the physiological growth of testes and to evaluate responses of the Leydig and Sertoli cells to early gonadotropin replacement. DESIGN AND METHODS: Two neonates (P1 with hypotuitarism and P2 with HH) with micropenis and microorchidism were treated for 6 months with high doses of recombinant LH and FSH (a gift of Luveris and Gonal-F from Serono, Lyon, France) delivered sc with an insulin pump. RESULTS: Gonadotropin continuous sc infusion increased mean serum LH and FSH to normal or supranormal levels. Mean testosterone increased from undetectable levels to 7.6 and 5.2 nmol/liter, respectively, in P1 and P2. Inhibin B and anti-Müllerian hormone increased to normal levels. Mean testicular volume increased from 0.45 to 0.57 ml at birth to 2.10 ml at 7 months. Stretched penile length increased from 8 to 30 mm (P1) and 12 to 48 mm (P2). CONCLUSIONS: The present regimen induced physiological postnatal testes growth and high-normal activation of Leydig and Sertoli cells.

rFSH in medically assisted procreation: Evidence for ovarian follicular hyperplasia and interest of mass spectrometry to measure 17-hydroxyprogesterone and Δ4-androstenedione in serum.

Ovarian monitoring requires the determination of serum estradiol and progesterone levels. We investigated whole follicular steroidogenesis under rFSH in medically assisted procreation (MAP: 26 IVF, 24 ICSI) compared to 11 controls (IUI). Estrone, estradiol, Δ4-androstenedione, testosterone, progesterone and 17-hydroxyprogesterone were measured by immunoassay and mass spectrometry except for estrogens. At the start of a spontaneous or induced cycle, steroids levels fluctuated within normal ranges: estradiol (314-585 pmol/L), estrone (165-379 pmol/L) testosterone (1.3-1.6 nmol/L), Δ4-androstenedione (4.5-5.6 nmol/L), 17-hydroxyprogesterone (2.1-2.2 nmol/L) and progesterone (1.8-1.9 nmol/L). 17-hydroxyprogesterone, Δ 4-androstenedione and estradiol predominated. Then estradiol and oestrone levels rise, but less markedly for oestrone in IUI. In MAP, rFSH injections induce a sharp increase in estrogens associated with a rise in 17-hydroxyprogesterone and Δ4-androstenedione levels, disrupting oestrogen/androgen ratios. rFSH stimulation induces an ovarian hyperplasia and Δ4pathway which could become abnormal. Determining 17-hydroxyprogesterone and Δ4-androstenedione levels with LC-MS/MS may therefore be useful in managing recurrent MAP failures.

Gonadal function is associated with cardiometabolic health in pre-pubertal boys with Klinefelter syndrome.

The most common sex chromosome aneuploidy, Klinefelter syndrome (KS), is associated with primary gonadal failure and increased morbidity and mortality from cardiometabolic disorders in adulthood. Children with KS also have a high prevalence of metabolic syndrome (MetS) features. To assess the relationship of gonadal and cardiometabolic function in children with KS, we evaluated serum hormones [gonadotropins, inhibin B (INHB), anti-mullerian hormone (AMH), total testosterone (TT)], and features of MetS (waist circumference, fasting lipid panel, fasting blood glucose (FBG), and blood pressure) in 93 pre-pubertal boys with KS age 4-12 years (mean 7.7 ± 2.5 years). The cohort was grouped by age and tanner stage, and biomarkers were compared to normal ranges. A total of 80% of this pre-pubertal cohort had ≥1 feature of metabolic syndrome (MetS) and 11% had ≥3 features of MetS. Risk of MetS was independent of age and body mass index. Sertoli cell dysfunction was common with 18% having an INHB below the normal range. A low INHB was associated with higher FBG, triglycerides, LDL, and lower HDL (p < 0.05). An INHB <50 ng/dL yielded a sensitivity of 83% and a specificity of 79% for having ≥3 features of MetS. INHB and AMH positively correlated with each other (p < 0.001), and high AMH was protective of MetS. TT was below the lower limit of normal in 49% of subjects, with mean values significantly lower than expected (3.3 ng/dL vs. 4.9 ng/dL, p < 0.0001), however, no convincing relationship between TT and MetS was seen. In conclusion, gonadal and cardiometabolic dysfunction are prevalent in pre-pubertal boys with KS. Although the relationship of testosterone deficiency and MetS is well-known, this study is the first to report an association between impaired Sertoli cell function and cardiometabolic risk.

Circulating leptin in normal children and during the dynamic phase of juvenile obesity: relation to body fatness, energy metabolism, caloric intake, and sexual dimorphism.

In 112 obese compared with 42 lean children, we found that serum leptin is elevated early in the evolution of childhood-onset obesity (28.4 +/- 1.4 vs. 4.5 +/- 0.4 ng/ml in lean children, P < 0.0001) and correlates with adiposity. Obese children also had higher serum leptin normalized to fat mass. Despite high serum leptin, obese children ingested 2-3 times more calories than did lean control subjects (P < 0.0001) and gained weight rapidly (10.2 +/- 0.3 vs. 2.9 +/- 0.1 kg/year in control subjects, P < 0.0001). Girls had higher leptin levels than did boys, in obese as well as in nonobese children, and showed a closer correlation between adiposity and serum leptin. Elevation of serum leptin was comparable before and after puberty in obese boys, but puberty further increased leptin levels in obese girls (36 +/- 3 ng/ml), resulting in a clear sexual dimorphism with pubertal obese boys (22 +/- 5 ng/ml, P < 0.005). In conclusion, increased serum leptin reflects but does not halt fat deposition in childhood obesity. After normalization to body adiposity, leptin was found to be increased independently by obesity status, female sex, and female sexual maturation.

Overexpression of placental leptin in diabetic pregnancy: a critical role for insulin.

Leptin, a small peptide produced by adipocytes, is implicated in an increasing number of endocrine regulations, including adiposity, satiety, puberty, and fertility. Although the factors involved in controlling maternal and fetal weight gain during pregnancy have not been fully elucidated, leptin has recently emerged as such a potential factor. In our study, we report the presence of high amounts of leptin mRNA and immunoreactive protein in the human placenta, establishing the placental synthesis of this hormone. A large (three- to fivefold) augmentation in leptin mRNA and protein was found in placentas from insulin-treated diabetic women. This finding was associated with increased concentrations of leptin and insulin in venous cord blood without modification of maternal circulating leptin levels. These data provide evidence that the placenta is a site for regulated leptin production in utero. Insulin is likely to play a critical role in this regulation, thus emphasizing the importance of placental leptin signaling in diabetic pregnancy.

A sib-pair analysis study of 15 candidate genes in French families with morbid obesity: indication for linkage with islet 1 locus on chromosome 5q.

As part of an ongoing search for susceptibility genes in obese families, we performed linkage analyses in 101 French families between qualitative and quantitative traits related to morbid obesity and polymorphisms located in or near 15 candidate genes whose products are involved in body weight regulation. These included cholecystokinin A and B receptors (CCK-AR and CCK-BR), glucagon-like peptide 1 receptor (GLP-1R), the LIM/homeodomain islet-1 gene (Isl-1), the caudal-type homeodomain 3 (CDX-3), the uncoupling protein 1 (UCP-1), the beta3-adrenoceptor (beta3-AR), the fatty acid-binding protein 2 (FABP-2), the hormone-sensitive lipase (HSL), the lipoprotein lipase (LPL), the apoprotein-C2 (apo-C2), the insulin receptor substrate-1 (IRS-1), the peroxisome proliferator-activated receptor-gamma (PPAR-gamma), tumor necrosis factor-alpha (TNF-alpha), and the liver carnitine palmitoyltransferase-1 (CPT-1). Phenotypes related to obesity such as BMI, adult life body weight gain, fasting leptin, insulin, fasting glycerol, and free fatty acids were used for nonparametric sib-pair analyses. A weak indication for linkage was obtained between the Isl-1 locus and obesity status defined by a z score over one SD of BMI (n = 226 sib pairs, pi = 0.54 +/- 0.02, P = 0.03). Moreover, a suggestive indication for linkage was found between the Isl-1 locus and BMI and leptin values (P = 0.001 and 0.0003, respectively) and leptin adjusted for BMI (P = 0.0001). Multipoint analyses for leptin trait with Isl-1 and two flanking markers (D5S418 and D5S407) showed that the logarithm of odds (LOD) score is 1.73, coinciding with the Isl-1 locus. Although marginally positive indications for linkage in subgroups of families were found with IRS-1, CPT-1, and HSL loci, our data suggested that these genes are not major contributors to obesity. Whether an obesity susceptibility gene (Isl-1 itself or another nearby gene) lies on chromosome 5q should be determined by further analyses.

Soluble leptin receptor in serum of subjects with complete resistance to leptin: relation to fat mass.

Leptin resistance and obesity have been related to mutations of the leptin receptor gene in rodents and, recently, in a consanguineous family. The latter mutation results in a receptor lacking transmembrane and intracellular domains. Homozygous and heterozygous individuals with this mutation had serum leptin levels higher than expected, given their BMIs: 600, 670, and 526 ng/ml and 145, 362, 294, 240, and 212 ng/ml, respectively. Their serum leptin was fractionated by gel filtration: >80% was present as a high-molecular size complex vs. 7.5% in the nonmutated sister. Western blot analysis showed a band at 146 kDa reacting specifically with an antibody directed against the leptin receptor ectodomain. In 10 obese control subjects, as in the mutated patients, free leptin levels correlated with BMI (r = 0.70, P = 0.0011) and reflected fat mass, regardless of leptin receptor functioning. In the patients, bound leptin levels correlated with BMI (r = 0.99, P = 0.0002) and were related to the number of mutated alleles. These data demonstrate that the truncated receptor is secreted into blood and binds the majority of serum leptin, markedly increasing bound and total leptin. Free serum leptin was similarly correlated with BMI in the mutated and nonmutated obese individuals, providing evidence that the relationship between BMI and circulating free leptin is preserved in this family. This finding suggests that the leptin receptor itself may not be specifically involved in the control of leptin secretion, and it supports the concept of relative resistance to leptin in common obesity.

Role of estradiol in the rise in follicle-stimulating hormone levels during the luteal-follicular transition.

Follicular recruitment takes place under FSH stimulation at the end of the luteal phase and the beginning of the subsequent follicular phase, the so-called luteal-follicular transition (LFT). Inhibin, a known suppressor of FSH, has been implicated in the onset of the rise in FSH levels, as the fall in its immunoreactive plasma levels after the demise of the corpus luteum has been shown to correlate negatively with the increase in FSH. To analyze the role of estradiol (E2), another inhibitor of FSH secretion in the LFT, we designed an experimental paradigm to dissociate the physiological falls in inhibin and E2. This was achieved by extending the duration of luteal plasma E2 levels with transdermal E2 treatment. Untreated ovulatory cycles in seven healthy female volunteers, aged 28-38 yr, were compared with E2-treated cycles in the same subjects, with treatment starting on the 10th day after the LH surge and continuing through the 4th day of the following menses [either 0.2 mg (n = 6; G1) or 0.1 mg (n = 6; G2) E2 daily]. Blood samples were obtained daily from the LH surge until the 11th day of the next cycle. Immunoreactive plasma inhibin levels reached a nadir on day 2 of menses regardless of whether women received E2. Plasma E2 (mean +/- SEM) levels remained within the normal luteal range (220 +/- 51 to 635 +/- 279 pmol/L) until the end of the treatment period in G2 (range, 253 +/- 40 to 382 +/- 62 pmol/L), but not in G1 (range, 598 +/- 195 to 1835 +/- 1259 pmol/L). However, the onset of the FSH rise was clearly delayed, from a mean of 2 days before menstruation in the controls to day 4 of the cycle in G1 and G2. Peak plasma FSH levels were attained within 6 days in the controls and within 2 or 3 days in both treatment periods. Our data suggest that it is the decrease in plasma E2 rather than inhibin that is the triggering signal for the LFT rise in plasma FSH. The exact roles of inhibin and other gonadal proteins (e.g. activins) in follicular recruitment remain to be determined.

Final height after long-term treatment with triptorelin slow release for central precocious puberty: importance of statural growth after interruption of treatment. French study group of Decapeptyl in Precocious Puberty.

The impact of treatment of central precocious puberty (CPP) with GnRH agonists on final statural height (FH) remains controversial, and guidelines on the optimal time point for interruption of these treatments have not been established. We analyzed the long term results of 58 girls and 8 boys uniformly treated with triptorelin slow release formulation (Decapeptyl, triptorelin-SR) for CPP and compared their FH with predicted height before treatment and with the FH of a historical group of patients not treated with GnRH agonist. The FH SD score was close to 0 and was not different from the genetic target height. In girls, FH was improved by 4.8 +/- 5.8 cm compared with predicted height before treatment and by 8.3 cm by comparison with a historical group. In boys, comparison with a historical group revealed a 13.7-cm improvement, whereas predicted height before treatment was similar to FH. Three variables were independently associated with FH in girls: the bone age/statural age ratio at the onset of treatment (negatively), the height SD score at the end of treatment, and the posttreatment growth spurt (delta FH - height at the end of treatment). The influence of the posttreatment growth spurt, itself dependent on age and bone age at the interruption of treatment, suggests that continuing treatment beyond the age of 11 yr in girls does not improve and could actually decrease FH. This point should be evaluated in a formal controlled trial.

Gonadotropin-releasing hormone agonists are unsuccessful in reducing tumoral gonadotropin secretion in two patients with gonadotropin-secreting pituitary adenomas.

Whether GnRH agonist treatment leads to reduced gonadotropin secretion and tumor volume in patients with gonadotropin-secreting pituitary adenomas is controversial. We studied the effect of GnRH analog treatment in two such patients, one with a recurrent FSH- and LH-secreting pituitary adenoma (patient 1) and one with a recurrent FSH- and alpha-subunit-secreting pituitary adenoma (patient 2). Patient 1 was treated with 200 micrograms Buserelin daily for 65 days, and patient 2 received three injections of 3 mg [D-Trp6]-LHRH formulated in microcapsules at 21-day intervals. In both patients, plasma FSH, LH (RIA), and alpha-subunit concentrations increased initially and remained above the pretreatment values throughout the treatment period. Plasma LH, measured by immunoradiometric assay, remained well above the detection limit. Plasma bioactive LH and testosterone became undetectable in patient 2, but did not change in patient 1. In neither patient did pituitary tumor size (determined by computed tomographic scan) change during treatment. We conclude that 1) the overall effect of GnRH analogs in patients with gonadotroph cell adenomas is stimulation of gonadotropin release by the tumor, although LH release varies according to how plasma LH is measured, possibly related to the origin of the hormone (normal or tumor gonadotroph cells), and 2) GnRH analog treatment does not reduce tumor size.

Long term treatment of male and female precocious puberty by periodic administration of a long-acting preparation of D-Trp6-luteinizing hormone-releasing hormone microcapsules.

The efficacy and safety of a delayed release formulation of the LHRH agonist D-Trp6-LHRH (LHRH-A; im microcapsules) were tested in 16 girls, 0.9-8.8 yr old, and 10 boys, 2.0-10.5 yr old, with precocious puberty. All children had advanced bone age, breast or testis enlargement, and a pubertal LH response to LHRH. Precocious puberty was idiopathic in 19 subjects and secondary to a brain tumor or other central nervous system abnormality in 7. Nine girls and 6 boys had been previously treated unsuccessfully with medroxyprogesterone and/or cyproterone acetate. The microcapsules were made of 2% LHRH-A dispersed in a biocompatible biodegradable polymeric matrix of DL-lactide-coglycolide. Sixty micrograms of LHRH-A/kg BW were given im on days 1 and 21 and thereafter every 4 weeks for 10-27 months. Plasma LHRH-A levels were measured in 13 children by means of a specific RIA. On days 3, 7, 14, and 21, mean concentrations (+/- SEM) were 295 +/- 44, 218 +/- 31, 215 +/- 45, and 224 +/- 39 pg/ml, respectively. In girls, breast enlargement disappeared, and mean uterus size decreased from 44.4 +/- 2.5 to 38.1 +/- 3.1 mm (mean +/- SEM; P less than 0.02) within 6 months. Mean ovary length decreased from 23.0 +/- 1.5 to 16.2 +/- 1.5 mm (P less than 0.01). In boys, mean testis volume decreased from 8.1 +/- 1.2 to 6.7 +/- 1.2 ml (P less than 0.02) within 6 months. In both sexes, growth velocity decreased significantly, and bone maturation was generally reduced. Plasma levels of estradiol or testosterone and FSH levels decreased significantly within 3 weeks. The LH response to LHRH was reduced to normal prepubertal values after 7 weeks. No secondary clinical or biochemical escape occurred. In 1 boy, all biological features of puberty recurred within 1 month after omission of the fifth injection. No side-effects occurred, except for transient vaginal bleeding in girls after the first or second injection. No antibodies to LHRH-A were detected in the patients' sera. This study demonstrates the ability of a delayed release formulation of LHRH-A to achieve stable levels of the drug in plasma for at least 21 days after a single im injection and to suppress pituitary and gonadal secretion and pituitary response to LHRH for as long as 2 yr after therapy. This treatment appears to be more efficient in treating both clinical and biochemical abnormalities than does treatment with inhibitory steroids. Additionally, the method of administration is more practical and ensures better patient compliance.

Resistance of hypogonadic patients with mutated GnRH receptor genes to pulsatile GnRH administration.

We have studied a kindred with three siblings with isolated hypogonadotropic hypogonadism caused by compound heterozygote mutations in the GnRH receptor gene. The disorder was transmitted as an autosomal recessive trait. The R262Q mutation in intracellular loop 3 of the receptor was associated with a mutation in the third transmembrane domain of the receptor, A129D, that has never been described before. This A129D mutation results in a complete loss of function, indicated by the lack of inositol triphosphate (TP3) 3 production by transfected Chinese hamster ovary (CHO) cells after GnRH stimulation. The two brothers had microphallus and bilateral cryptorchidism and were referred for lack of puberty, whereas their sister had primary amenorrhea and a complete lack of puberty. Their basal gonadotropin concentrations were below the reference range, and their endogenous LH secretory patterns were abnormal, with a low-normal frequency of small pulses or no apparent LH pulse. Pulsatile GnRH administration (10 microg/pulse every 90 min for 40 h) resulted in increased mean LH without any significant changes in testosterone levels in the two brothers, whereas the LH secretory profile of their sister remained apulsatile. Larger pulses of exogenous GnRH (20 microg every 90 min for 24 h) caused the sister to produce recognizable low amplitude LH pulses. The concentrations of free alpha-subunit significantly increased in all patients during the pulsatile GnRH administration. Thus, these hypogonadal patients are partially resistant to pulsatile GnRH administration, suggesting that they should be treated with gonadotropins to induce spermatogenesis or ovulation rather than with pulsatile GnRH.

Macroorchidism due to autonomous hyperfunction of Sertoli cells and G(s)alpha gene mutation: an unusual expression of McCune-Albright syndrome in a prepubertal boy.

We report an unusual observation of a 3.8-yr-old boy with McCune-Albright syndrome (MAS) associated with abnormal prepubertal testis enlargement and no sexual precocity. Physical examination showed café-au-lait skin lesions, enlarged testes, prepubertal sized penis, and no pubic or axillary hair. Skeletal radiography disclosed fibrous dysplasia. The serum testosterone level was 0.58 nmol/L and remained below 1.4 nmol/L during the 4-yr follow-up. By contrast, serum inhibin B and anti-Mullerian hormone concentrations were abnormally increased up to 255 pg/mL (childhood range, 35--180) and 792 pmol/L (childhood range, 309--566), respectively. The LH response to a GnRH test was in the prepubertal range, whereas the FSH response was blunted. This abnormal hormone concentration profile indicates autonomous hyperfunction of Sertoli cells, with no evidence of Leydig cell activation. Testicular histology showed tubules with marked Sertoli cell hyperplasia and very rare germinal cells, and interstitial tissue containing mesenchymal cells but no mature Leydig cells. DNA sequence analysis from bone and testis tissues detected the known activating mutation in MAS that results in replacement of Arg by His at codon 201 of the G(s)alpha protein. Other endocrine tests showed excessive GH secretion and moderate adrenal androgen hypersecretion. These findings are consistent with the occurrence of an activating mutation of the G(s)alpha gene mainly expressed in Sertoli cells and weakly expressed or absent in Leydig cells. Abnormal prepubertal testicular enlargement extends the clinical spectrum of MAS, suggesting that determination of serum inhibin B and anti-Mullerian hormone should be considered in boys with this syndrome. This observation demonstrates the usefulness of detailed molecular and biological investigations in atypical cases of MAS.

Gonadotropin and alpha-subunit secretion during long term pituitary suppression by D-Trp6-luteinizing hormone-releasing hormone microcapsules as treatment of precocious puberty.

Short term treatment with GnRH agonists has been reported to increase plasma gonadotropin alpha-subunit (Gn alpha) levels while decreasing plasma immunoreactive LH (IR-LH) levels. In this study we examined the effect of D-Trp6-LHRH (LHRH-A) in microcapsules (60 micrograms/kg, im, every 28 days for 1 yr) in 13 girls suffering from precocious puberty. Plasma IR-Gn alpha was measured by RIA; plasma IR-LH and IR-FSH were measured by both polyclonal RIAs and monoclonal immunoradiometric assays (IRMA). Before treatment, basal IR-LH and IR-FSH levels and peak responses to LHRH measured by both RIA and IRMA were similar, and the Gn alpha response paralleled that of LH. After the first injection of LHRH-A, RIA LH levels were significantly higher than pretreatment levels until day 21, while IRMA LH levels transiently increased, but returned to pretreatment levels by day 7 and became lower thereafter (P less than 0.005). Plasma IR-Gn alpha levels increased from days 3-21 (P less than 0.05). After 1.5 months of treatment, basal RIA LH levels remained detectable and not different from pretreatment levels; IRMA LH levels were very low. The mean RIA and IRMA LH responses to LHRH were decreased at 1.5 and 12 months (P less than 0.01). Basal plasma RIA and IRMA FSH levels were similar during treatment (P greater than 0.05) and significantly lower than pretreatment values (P less than 0.01). The mean RIA and IRMA FSH responses to LHRH decreased significantly at 1.5 months (P less than 0.001). After 12 months, both RIA and IRMA FSH responses were increased, but IRMA values were significantly lower than RIA values. A sustained increase in basal Gn alpha values occurred, but there was a tendency for the peak levels after LHRH treatment to decrease, becoming significantly lower than pretreatment peak levels after 1 yr. The chromatographic analysis on Sephadex G-100 of a pool of plasma samples collected during a LHRH test in three children treated for 6 months indicated that IR-Gn alpha coeluted with [125I]Gn alpha. The large discrepancy between RIA and IRMA LH values suggests the secretion of unusual LH molecules which are recognized by RIA but not by IRMA. The sustained release of large amounts of IR-Gn alpha indicates dissociated effects of LHRH-A on alpha- and beta-subunit secretion by the gonadotrophs. The sustained response of Gn alpha to LHRH demonstrates that gonadotroph cell LHRH receptors are still responsive to LHRH during treatment with a LHRH agonist.

A spontaneous and severe hyperstimulation of the ovaries revealing a gonadotroph adenoma.

We report an unusual case of a gonadotroph adenoma in a 34-yr-old woman, revealed by a dramatic rise in the plasma estradiol (E2) concentration (26,800 pmol/L; normal, <370), with nonsuppressed FSH and LH levels (4.9 and 2.4 mIU/mL, respectively). The PRL level was 503 ng/mL. The testosterone and progesterone levels were 7 and 17 nmol/L, respectively. The levels of inhibin alpha, inhibin A, and inhibin B were increased compared to normal values in both the follicular (fp) and luteal (lp) phases of the menstrual cycle [inhibin alpha, 1986 IU/L (fp normal, <700; lp normal, <1650); inhibin A, 254 pg/mL (fp normal, <20; lp normal, <120); inhibin B, 246 pg/mL (fp normal, <150; lp normal, <30 lp)]. Pituitary magnetic resonance imaging revealed a huge pituitary adenoma. After transphenoidal surgery, the patient presented with pituitary insufficiency and diabetes insipidus. RT-PCR of the tumor tissue was positive for LHbeta, FSHbeta, alpha-subunit, and PRL. This case is of particular interest because 1) although the E2 level was extremely high, the patient did not present with ascitis, suggesting that chronic elevated E2 does not play a crucial role in the hyperstimulation symptoms; 2) the extreme rise in E2 was related to the cosecretion of FSH and LH, confirming the two-cell two-gonadotropin theory; and 3) the rise in inhibin B is associated with FSH secretion, whereas the rise in inhibin A is probably due to luteinization.