Arterial Stiffness in Transgender Men Receiving Long-Term Testosterone Therapy

Context

The effects of androgen therapy on arterial function in transgender men (TM) are not fully understood, particularly concerning long-term androgen treatment.

Objective

To evaluate arterial stiffness in TM receiving long-term gender-affirming hormone therapy by carotid-femoral pulse wave velocity (cf-PWV).

Design

A cross-sectional case-control study.

Setting

Gender Dysphoria Unit of the Division of Endocrinology, HC-FMUSP, Sao Paulo, Brazil.

Patients

Thirty-three TM receiving intramuscular testosterone (T) esters as regular treatment for an average time of 14 ± 8 years were compared to 111 healthy cisgender men and women controls matched for age and body mass index (BMI). Aortic stiffness was evaluated by cf-PWV measurements using the Complior® device post-testosterone therapy.

Main outcome measures

Aortic stiffness by carotid-femoral pulse wave velocity (cf-PWV) as a cardiovascular risk marker in transgender men and control group.

Results

The cf-PWV after long-term testosterone therapy was significantly higher in TM (7.4 ± 0.9 m/s; range: 5.8–8.9 m/s) than in cisgender men (6.6 ± 1.0 m/s; range: 3.8–9.0 m/s, p < 0.01) and cisgender women controls (6.9 ± 0.9 m/s; range: 4.8–9.1 m/s, p = 0.02). The cf-PWV was significantly and positively correlated with age. Analysis using blood pressure as a covariate showed a significant relationship between TM SBP and cf-PWV in relation to cisgender women but not to cisgender men. The age, the SBP and the diagnosis of hypertension were independently associated with cf-PWV in transgender men group.

Conclusions

The TM group on long-term treatment with testosterone had higher aging-related aortic stiffening than the control groups. These findings indicate that aortic stiffness might be accelerated in the TM group receiving the gender-affirming hormone treatment, and suggest a potential deleterious effect of testosterone on arterial function. Preventive measures in TM individuals receiving testosterone treatment, who are at higher risk for cardiovascular events, are highly recommended.

Sexuality and fertility desire in a large cohort of individuals with 46, XY differences in sex development

OBJECTIVE

To analyze aspects of sexual life and fertility desire among 46, XY DSD people, including those who changed their gender.

METHODS

It is a cross-sectional study including 127 adults (> 16 years of age) with 46, XY DSD (83 females; 44 males) from a Single Brazilian Tertiary-Care Medical Center.

RESULTS

Sexual fantasies and masturbation were more frequent in 46, XY DSD males, whereas orgasm and sexual life satisfaction were similar in both genders. More 46, XY DSD men than women had a long-term romantic relationship. 46, XY DSD women with prenatal androgen exposure reported more fear of being romantically rejected. External genitalia appearance at birth did not impact the sexuality of 46, XY DSD women after surgical genital treatment had been completed. Overall, the sexual life was similar between 46, XY men assigned as males and those who changed to the male gender. Regarding sexual orientation, most self-reported as heterosexual (91% and 92% of women and men, respectively). The desire for fertility had a similar prevalence in both genders, but more women than men considered infertility a barrier to a long-term romantic relationship. Twelve individuals (7 males) had children; 10 out of 12 have adopted children.

CONCLUSION

Fertility desire was shared among 46, XY DSD people, regardless of gender. Prenatal androgen exposure reduced the desire for motherhood in 46, XY women. 46, XY DSD people who changed from female to male gender presented similar sexual parameters as those assigned as males. Among females, virilized genitalia at birth did not affect sexuality once the surgical treatment is completed.

Insights from the genetic characterization of central precocious puberty associated with multiple anomalies

STUDY QUESTION

Is there an (epi)genetic basis in patients with central precocious puberty (CPP) associated with multiple anomalies that unmasks underlying mechanisms or reveals novel genetic findings related to human pubertal control?

SUMMARY ANSWER

In a group of 36 patients with CPP associated with multiple phenotypes, pathogenic or likely pathogenic (epi)genetic defects were identified in 12 (33%) patients, providing insights into the genetics of human pubertal control.

WHAT IS KNOWN ALREADY

A few studies have described patients with CPP associated with multiple anomalies, but without making inferences on causalities of CPP. Genetic-molecular studies of syndromic cases may reveal disease genes or mechanisms, as the presentation of such patients likely indicates a genetic disorder.

STUDY DESIGN, SIZE, DURATION

This translational study was based on a genetic-molecular analysis, including genome-wide high throughput methodologies, for searching structural or sequence variants implicated in CPP and DNA methylation analysis of candidate regions.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A cohort of 197 patients (188 girls) with CPP without structural brain lesions was submitted to a detailed clinical evaluation, allowing the selection of 36 unrelated patients (32 girls) with CPP associated with multiple anomalies. Pathogenic allelic variants of genes known to cause monogenic CPP (KISS1R, KISS1, MKRN3 and DLK1) had been excluded in the entire cohort (197 patients). All selected patients with CPP associated with multiple anomalies (n = 36) underwent methylation analysis of candidate regions and chromosomal microarray analysis. A subset (n = 9) underwent whole-exome sequencing, due to presenting familial CPP and/or severe congenital malformations and neurocognitive abnormalities.

MAIN RESULTS AND THE ROLE OF CHANCE

Among the 36 selected patients with CPP, the more prevalent associated anomalies were metabolic, growth and neurocognitive conditions. In 12 (33%) of them, rare genetic abnormalities were identified: six patients presented genetic defects in loci known to be involved with CPP (14q32.2 and 7q11.23), whereas the other six presented defects in candidate genes or regions. In detail, three patients presented hypomethylation of DLK1/MEG3:IG-DMR (14q32.2 disruption or Temple syndrome), resulting from epimutation (n = 1) or maternal uniparental disomy of chromosome 14 (n = 2). Seven patients presented pathogenic copy number variants: three with de novo 7q11.23 deletions (Williams–Beuren syndrome), three with inherited Xp22.33 deletions, and one with de novo 1p31.3 duplication. Exome sequencing revealed potential pathogenic variants in two patients: a sporadic female case with frameshift variants in TNRC6B and AREL1 and a familial male case with a missense substitution in UGT2B4 and a frameshift deletion in MKKS.

LIMITATIONS, REASONS FOR CAUTION

The selection of patients was based on a retrospective clinical characterization, lacking a longitudinal inclusion of consecutive patients. In addition, future studies are needed, showing the long-term (mainly reproductive) outcomes in the included patients, as most of them are not in adult life yet.

WIDER IMPLICATIONS OF THE FINDINGS

The results highlighted the relevance of an integrative clinical-genetic approach in the elucidation of mechanisms and factors involved in pubertal control. Chromosome 14q32.2 disruption indicated the loss of imprinting of DLK1 as a probable mechanism of CPP. Two other chromosomal regions (7q11.23 and Xp22.33) represented new candidate loci potentially involved in this disorder of pubertal timing.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by grant number 2018/03198-0 (to A.P.M.C.) and grant number 2013/08028-1 (to A.C.V.K) from the São Paulo Research Foundation (FAPESP), and grant number 403525/2016-0 (to A.C.L.) and grant number 302849/2015-7 (to A.C.L.) and grant number 141625/2016-3 (to A.C.V.K) from the National Council for Scientific and Technological Development (CNPq). The authors have nothing to disclose.

TRIAL REGISTRATION NUMBER

N/A.

SUN-081 High Throughput Genetic Analysis Revealed Novel Genomic Loci and Candidate Genes Involved in Central Precocious Puberty Associated with Complex Phenotypes

Background: Central precocious puberty (CPP) is mostly described as an isolated entity. Few studies have shown an association of CPP with complex cases or genetic syndromes, but without making inferences on molecular causalities.

Objective: To genetically investigate a cohort of patients with CPP associated with complex phenotypes using high throughput methodologies.

Patients and methods: From a large cohort of patients with idiopathic CPP followed at a university hospital outpatient clinic, thirty-eight patients were selected for high throughput genetic investigation for presenting at least 3 additional clinical features and conditions, characterizing complex phenotypes. All had normal brain MRI. Pathogenic allelic variants in CPP known genes were initially excluded. All patients were submitted to genomic microarray (SNP or CGH arrays). A subset of patients was also submitted to whole-exome sequencing (11 cases) or target panel sequencing (18 cases).

Results: Among the group of 38 patients (35 girls, 4 boys; 21 sporadic, 17 familial), mean age at puberty onset was 5.8 ±2.1 and 8.3 ±3.0 yr in girls and boys, respectively. The more prevalent clinical features described included metabolic, growth and neurocognitive phenotypes; less prevalent features included dysmorphic features and congenital anomalies. Pathogenic or probably pathogenic genetic defects were identified in 9 cases: 5 sporadic (all identified as de novo) and 4 familial. Defects in sporadic cases were as follows: three cases with 7q11.23 deletion (Williams syndrome); one girl with ventricular arrhythmia presenting a rare 1p31.3 duplication, involving NFIA gene coding a transcription factor of NFI family with hypothalamic expression; and one girl with imperforate anus and learning difficulties with rare frameshift variants in AREL1 gene (p.Ser229Aspfs*3) coding an ubiquitin ligase, and TNRC6B gene (p.Gly665Leufs*35) coding a regulator of translational inhibition. In the four familial cases, the genetic defects segregated with CPP in a dominant inheritance mode. Three cases from unrelated families presented growth phenotypes and Xp22.33 deletions, including SHOX gene and other elements. One boy with maternal familial CPP and autism had two rare potentially pathogenic variants: a frameshift deletion in MKKS gene (p.Phe144Leufs*14); and a missense variant (p.Pro267Leu) in UGT2B4 gene. Interestingly, the later gene encodes a protein involved in estrogen hydroxylation and is associated to menarche timing in GWAS.

Conclusion: Novel genetic defects were identified in 23% cases of CPP associated with complex phenotypes. Three chromosomal regions represented loci potentially implicated in CPP: Xp22.33, 7q11.23 and 1p31.3. Five genes were identified as candidate genes associated with CPP: NFIA, AREL1, TNRC6B, MKKS and UGT2B4.

OR15-04 Central Precocious Puberty without Central Nervous System Lesions: Is It Really Idiopathic?

Background: The etiological diagnosis of central precocious puberty (CPP) has been classically divided into causes with or without central nervous system (CNS) lesions. Among the cases without CNS lesions, most of them are classified as idiopathic. In clinical practice, about 90% of girls and 40% of boys with CPP are considered having the idiopathic form. In the last two decades, pioneering studies have revealed underlying genetic causes in patients with apparently idiopathic CPP.

Objective: To describe the frequency of genetic causes identified in a large cohort of patients with CPP followed in a single research center and to evaluate its role in the distribution of the etiology of CPP.

Patients and methods: A retrospective evaluation was performed analyzing the etiological diagnosis of 276 patients (246 girls, 30 boys) with CPP followed in a single university hospital outpatient clinic from 2006 to 2019. The great majority (230 patients) presented without CNS lesions, being classified as idiopathic CPP group. Among the idiopathic CPP group, 170 of them had DNA samples available and were included for genetic analysis. Patients included for genetic analysis were systematically investigated for genetic causes of CPP using standard methodologies of genetic-molecular analysis. Briefly, they were studied as follows: 120 by Sanger sequencing; 18 by target panel sequencing; 27 by whole-exome sequencing; 5 by whole-genome sequencing; 113 by specific DNA methylation analysis; and 38 by genomic microarray.

Results: Among the 276 patients with CPP, 46 (16.7%) had pathological CNS lesions: 19 boys and 27 girls, indicating the prevalence of CPP with CNS lesions (organic) of 63.3% in boys and 11% in girls. The most common cause of organic CPP was hypothalamic hamartoma (20 cases). Meanwhile 230 patients (83.3%) encompassed the apparently idiopathic CPP group. Main characteristics of this idiopathic CPP group were: 219 girls and 11 boys; 158 sporadic (69%), 68 familial (29.5%) and 4 adopted (1.5%). In the subset of patients with DNA available (162 girls, 8 boys), the frequency of genetic causes was 11.8% (20 cases: 18 girls and 2 boys). Analyzing by sex, the frequency of genetic causes was higher in boys (25%) than in girls (11.1%). The identified genetic defects were the following: 9 cases with inactivating MKRN3 mutations (8 families), 6 cases with inactivating DLK1 mutations (2 families), 1 case with activating KISS1R mutation, 1 case with activating KISS1 mutation, 2 sporadic cases with maternal uniparental disomy of chromosome 14, and 1 sporadic case with epimutation at DLK1 locus.

Conclusion: Pathogenic genetic defects were identified in 11.8% of patients with apparently idiopathic CPP involving four distinct genes. Altogether, these genetic findings indicate a context of changing in the distribution of the etiological diagnosis of CPP in both sexes, highlighting the genetic causes.

SUN-089 Novel Genetic and Biochemical Findings of DLK1 Deficiency in Children with Central Precocious Puberty - a Collaborative Brazilian-Spanish Study

Background: Delta-like 1 homolog (DLK1), also known as pre-adipocyte factor 1 (Pref-1), is part of the Notch signaling pathway that controls many developmental processes. Loss-of-function mutations of DLK1 have been identified in children with central precocious puberty (CPP), as well as in women who had precocious menarche (≤ 9 years) with an unfavorable metabolic profile. Objective: To investigate genetic and biochemical aspects of DLK1 in a cohort of children with CPP. Patients: A large cohort of Spanish children with idiopathic CPP (Spanish PUBERE Registry) was studied. Genomic DNA was obtained from 444 individuals, including 168 index cases with CPP and their close relatives. Automatic sequencing of the coding region (5 exons) of DLK1 was performed in all index cases. Serum DLK1 levels were measured by using a soluble DLK1 enzyme-linked immunosorbent assay (ELISA). Results: A rare allelic deletion (c.401_404 + 8del) of a splice site junction of DLK1 was identified in a girl with sporadic CPP. Pubertal signs appeared at 5.7 years of age with progressive puberty (basal LH: 1.7 mIU/mL, peak LH: 32.77 mIU/mL; basal FSH: 6.32 mIU/mL, peak FSH: 19.89 mIU/mL), BA/CA 1.7 years; normal cranial MRI). She received LHRH analogues (6.3 - 10.1 years of CA) with no side effects. At 14.9 years of age height and BMI are 152.9 cms and 18 kg/m², respectively, presenting regular menses. Familial segregation analysis showed that the affected child was the only carrier of this deletion characterizing a de novo mutation (biological paternity and maternity were confirmed by microsatellite analysis). Serum DLK1 levels were undetectable (<0.4 ng/mL) in this girl, supporting that the deletion lead to complete lack of DLK1 production. Her father, mother and sister had normal serum DLK1 levels (ranged 6.36 ng/mL to 8.98 ng/mL). Two rare consecutive nucleotide changes in the promoter region of the DLK1 gene (c.-222 C>A and c.-223 G>A) were also identified in an adopted child with CPP. They are located in a transcription factor binding site for SP1 (a zinc finger transcription factor). Pubertal signs appeared at 6.7 years of age with progressive puberty (Basal LH: 0.5 mIU/mL, peak LH: 15.9 mIU/mL, basal FSH: 1.52 mIU/mL, peak FSH: 6.56 mIU/mL, BA/CA 1.4 years; normal cranial MRI). She is under therapy with LHRH analogues with no side effects. Conclusion: Novel DLK1 findings were identified in the Spanish cohort of children with CPP, reinforcing a significant role of this factor in human pubertal timing.

SUN-090 Investigation of Imprinting Defects in MKRN3 and DLK1 in Children with Idiopathic Central Precocious Puberty Through Specific DNA Methylation Analysis

Background: Loss of imprinting has been implicated in the pathogenesis of several human diseases. Monogenic causes of central precocious puberty (CPP) were identified in families with loss-of-function mutations affecting mainly the coding region of two paternally expressed imprinted genes: Makorin ring finger 3 (MKRN3) and Delta-like 1 homolog (DLK1). The role of imprinting defects involving these two genes in CPP has not been described so far.

Objective: To investigate the methylation status at primary differentially methylated regions (DMR) of MKRN3 and DLK1 in a cohort of children with idiopathic CPP.

Patients and methods: One-hundred and twenty CPP patients (112 sporadic, 8 familial; 115 females, 5 males) were selected for analysis. Leukocyte DNA was obtained from all patients. MKRN3 and DLK1 pathogenic allelic variants were first excluded by DNA sequencing analysis. Bisulfite treatment followed by Allele-Specific Methylated Multiplex Real-Time Quantitative PCR was performed with leukocyte DNA, analyzing separately the methylation index (MI) of MKRN3:TSS-DMR and DLK1/MEG3:IG-DMR for each patient. The MI results were compared with controls with normal pubertal development.

Results: Mean age at puberty onset was 5.8 ±1.9yr for girls and 7.2 ±2.6yr for boys. Hypomethylation at DLK1/MEG3:IG-DMR was identified in 3 patients (I, II and III) with sporadic CPP: MI 10%, 16% and 11%, respectively. Interestingly, cases II and III were both girls who had been firstly referred to pediatric endocrinology for presenting precocious menarche; while case I was a boy who had been referred for presenting mild growth retardation, and developed CPP during monitoring. In addition, during follow-up, other clinical findings were noticed: being born small for gestational age, prominent forehead, small hands/feet, overweight/obesity and early onset type 2 diabetes in case III. Additional genetic investigation included SNP array in cases I and II, identifying a maternal uniparental disomy at chromosome 14 (upd(14)mat). Meanwhile, case III had normal genomic microarray and microsatellites analysis, excluding copy number variants and upd(14)mat, and indicating a mechanism of epimutation at DLK1/MEG3:IG-DMR. Uniparental disomy and epimutation are molecular mechanisms associated with the imprinting disorder known as Temple syndrome. In the remaining cases, mean MI for DLK1/MEG3:IG-DMR was 49±2%. In all cases, mean MI for MKRN3:TSS-DMR was 49±6%. There were no significant correlations between age at puberty onset and MI for MKRN3 (p=0.69) and DLK1(p=0.45).

Conclusion: There was no leukocyte DNA methylation defect at MKRN3 imprinting control region in the idiopathic CPP cohort. DLK1/MEG3:IG-DMR hypomethylation was identified in 3 patients with CPP and additional findings of Temple syndrome, indicating that loss of effective imprinting of DLK1 locus is a mechanism leading to CPP.

SUN-061 Anthropometric and Reproductive Outcomes of Patients with Gonadotropin-Independent Precocious Puberty Due to McCune-Albright Syndrome After Treatment with Distinct Therapeutic Agents

Ovarian estrogen-secreting cysts leading to peripheral precocious puberty (PPP) are some of the major clinical manifestations of the McCune-Albright syndrome (MAS). Therapeutic options for PPP of MAS include tamoxifen, progestational agents, aromatase inhibitors (AI) and anti-androgens that aiming to block sex steroid synthesis or action. Here, we described the anthropometric and reproductive follow-up of patients with PPP of MAS treated with distinct therapeutic agents. Thirteen unrelated girls with MAS were studied. They had PPP combined with café-au-lait spots or/and fibrous dysplasia. All patients were treated with one or more of the following agents: tamoxifen, medroxyprogesterone acetate, aromatase inhibitors (anastrozole or letrozole) and anti-androgens (cyproterone), and, in cases with secondary gonadotropic axis activation, depot GnRHa was used. Patients were evaluated every three months, when height, weight, and Tanner pubertal stage were determined. Vaginal bleeding or other adverse effects were also reviewed. The chronological age (CA) at the diagnosis of PPP was 5.9 ± 2.35 (2.4 to 10.2 years). Thelarche and vaginal bleeding were the first manifestations in 76.9% and 53%, respectively. The first choice of treatment was tamoxifen in 30.7% of the patients, followed by aromatase inhibitors (23%) and medroxyprogesterone acetate in 23% of them. Tamoxifen plus medroxyprogesterone, or cyproterone, or leuprorelin were used (each one) as the first choice in 1 patient (7.6%). Eight patients (61%) presented secondary central precocious puberty and were treated with depot GnRHa. Vaginal bleeding was recurrent in 70% of patients, during treatment. Progression of breast Tanner stage during treatment occurred in 78% of the patients. The great majority (80%) of girls presented bone age (BA) advancement at the diagnosis of PPP (mean Δ BA - CA of 3.2±1.3 yr), which was normalized for chronological age in all except one patient. The mean duration of treatment was 5.8 ± 3.4 yr (ranging from 1 to 12 yr). Three patients are still under medical treatment. Hypertrichosis and uterine enlargement were the main side effects of tamoxifen in 3 and 5 patients, respectively. One patient treated with letrozole presented laboratory hyperandrogenism. Ten patients reached their adult height (149.9 ± 7.9 cm), 60% of them were below their target height. Menarche occurred at a median age of 11.8 yr (10.4 to 14 y), and all but one patient presented regular menstrual cycles. One patient spontaneously became pregnant. Despite a reasonable number of treatment options for peripheral PP in MAS, none of them showed proven effective results in stopping vaginal bleeding, reduce pubertal progression and preserving potential genetic adult height. Therefore, due to the extremely heterogeneous nature of PPP of MAS, the clinical treatment remains a challenge.

SUN-085 Clinical and Hormonal Features of 37 Families with Central Precocious Puberty Due to MKRN3 Loss-Of -Function Mutations

Context: Loss-of-function mutations in the maternally imprinted Makorin RING-finger 3 (MKRN3) gene (15q11.2) are the most prevalent cause of familial central precocious puberty (CPP). Objectives: To analyze the phenotypes of a large cohort of children with CPP due to MKRN3 mutations and to compare them with the phenotypes of idiopathic CPP. Setting and Participants: We studied 73 individuals from 37 families with mutations in MKRN3 originating from nine different countries. The phenotypes of these patients at initial diagnosis were compared to a cohort of 124 patients with idiopathic CPP. Additionally, expression of nine different genes implicated with pubertal timing, including MKRN3, was performed in the hypothalamus of female mice in different phases of sexual maturation. Results: Nineteen different heterozygous, paternally inherited mutations in MKRN3 were identified in 73 patients with CPP (48 girls and 25 boys). Six MKRN3 mutations were frameshifts, one introduced a premature stop codon, 11 were missense mutations predicted to be pathogenic, and one was a deletion in the promoter region. A frameshift mutation affecting codon 161 in the amino terminal region of the protein was the most frequent MKRN3 defect (46%), representing a hotspot region. Among the cohort with MKRN3 mutations, first pubertal signs occurred at 6·2 ± 1·2 years in girls and 7·6 ± 1·4 years in boys. Patients harboring severe frameshift/nonsense mutations did not differ significantly in any clinical or hormonal parameters compared to the 20 patients with missense variants. However, when the 48 girls with MKRN3 mutations were compared with 124 idiopathic CPP girls, some parameters could be considered as possible predictors of the genetic cause: a lower age at first medical appointment (7·1 ± 1·1 in the MKRN3 group vs. 8·0 ± 2 years in the idiopathic group; p&lt; 0.001) and a shorter time interval between puberty onset and medical assistance (0·8 ± 0·8 vs 2·2 ± 2·1 years; p&lt; 0.001). Interestingly, the other predictor of MKRN3 mutations was a higher basal FSH level (5·1 ± 2·3 vs 3·9 ± 2·7 IU/L; p = 0.017) at first evaluation, although no cutoff value yielded good accuracy. Patients originating from European/Mediterranean countries were more likely to have missense variants (56% of all mutations) than North American and South American (23%) counterparts (p &lt;0.001). Mouse Mkrn3 mRNA levels in the arcuate nucleus were highest in the prepubertal phase when compared with expression of other genes and Mkrn3 decreased progressively through puberty and adult ages. Conclusions: Different types of loss-of-function MKRN3 mutations were associated with premature sexual development in both sexes. Their phenotypes were relatively uniform, regardless of the mutation type. Clinical features of children with MKRN3 mutations were similar to the idiopathic CPP group.

SUN-725 Clinical and Genetic Features of Families with Maternally Inherited Central Precocious Puberty

Context: The clinical recognition of familial central precocious puberty (CPP) has significantly increased in the last years. This fact can be related to the recent descriptions of genetic causes associated with this pediatric condition, such as loss-of-function mutations of two imprinted genes (MKRN3 and DLK1). Inherited defects in both genes cause paternally inherited CPP. However, no genetic abnormality has been described in families with maternally inherited CPP so far.

Objectives: To characterize the clinical and genetic features of several families with maternally inherited CPP.

Setting and Participants: We analyzed clinical and genetic features of children with familial CPP. No brain MRI alterations were detected in the selected patients with CPP. MKRN3 and DLK1 pathogenic mutations were excluded. Whole-exome sequencing was performed in selected cases.

Results: We studied 177 children from 141 families with familial CPP. Paternal inheritance was evidenced in 44 families (31%), whereas 58 (41%) had maternally inheritance. Indeterminate inheritance was detected in the remaining families. Maternally inherited CPP affected mainly female patients (69 girls and two boys). Thelarche occurred at mean age of 6.1 ± 1.9 years in this female group. Most of girls had Tanner 3 (41%) and Tanner 4 (35%) breast development at first evaluation. One boy had additional syndromic features (macrosomia, autism, bilateral eyelid ptosis, high arcade palate, irregular teeth and abnormal gait). The pedigree analysis of patients with maternally inherited CPP revealed the following affected family members: 42 mothers, 10 grandmothers, 11 sisters, 12 aunts, and 11 female cousins. Most of the families (41) had two affected consecutive generations, while eight families had three affected generations. No consanguinity was referred. Ongoing molecular analysis revealed two rare heterozygous variants in the boy with syndromic CPP and three affected family members with precocious menarche (mother, maternally half-sister, and maternally aunt): a frameshift deletion (p.F144fs) in MKKS; and a missense variant (p.P267L) in UGT2B4, which encodes a protein involved in estrogen hydroxylation and it was related to menarche timing in genome-wide association studies.

Conclusions: Maternally inherited CPP was diagnosed mainly in girls, who had thelarche at mean age of 6 years old. Dominant pattern of inheritance was more prevalent, with direct maternal transmission in 72% of the studied families. New candidate genes might be implicated with maternally inherited CPP.

SAT-227 Long-Term Outcomes of Two Siblings with X-Linked Congenital Adrenal Hypoplasia Due to a Mutation in NR0B1 (DAX1) Gene: Reproductive and Neuropsychiatric Aspects

Background: X-linked congenital adrenal hypoplasia (CAH) is a rare disease caused by mutations in the NR0B1 (DAX-1) gene. Non-classical manifestations have been described, including late-onset adrenal insufficiency (AI) and gonadotropin-independent precocious puberty (GIPP). We report long-term endocrine and neuropsychiatric outcomes of two siblings with CAH due to mutation in NR0B1.Case report: A 2-yr-old boy was referred due to progressive clinical signs of puberty since 6 months of age. At the age of 3 yr, AI was diagnosed, and the molecular analysis revealed a mutation in the NR0B1 (p.Cys65Leufs*6). Glucocorticoid replacement resulted in reduced testicular volume and decreased testosterone levels. At 11 yr, cyproterone acetate was indicated due to pubertal progression and bone age advancement. At 17 yr the patient had incomplete sexual development and no pubarche. Testosterone levels declined, despite pubertal levels of basal and GnRH-stimulated gonadotropin levels, indicating partial hypogonadotropic hypogonadism. Adult height was 156 cm (SDS: -2.7) within his target height of 161 cm (SDS: -2.1). This patient also presented a psychiatric diagnosis of mood disorder and attention-deficit/hyperactivity disorder (ADHD), and was under methylphenidate, topiramate and sertraline. Both the patient and his mother had SNP array performed, which excluded contiguous gene syndrome. His younger brother also harbored the same mutation in the NR0B1, confirmed shortly after birth. AI was diagnosed with 1 month of age. Cortisone acetate and fludrocortisone were initiated. At 11 months of age, he presented signs of pubertal development with an elevated ACTH and testosterone levels with suppressed gonadotropins, confirming the diagnosis of GIPP. He was treated with cyproterone acetate. At 8 yr, a pubertal response to the GnRH test was detected, and leuprorelin was added. At 9 yr, due to the low growth velocity and advanced bone age, rhGH was started. However, this patient presented a poor compliance and severe obesity (BMI 33 kg/m²). Treatment for GIPP and secondary CPP was stopped at 10 yr, with bone age of 13.5 yr and height of 151 cm (SDS: - 2.3). The diagnosis of ADHD and autism spectrum disorder was made after neuropsychiatric assessment and the patient received treatment with methylphenidate and sertraline. Conclusion: Pubertal development of patients with CAH due to NR0B1 mutations can be heterogeneous. However, the intriguing neuropsychiatric features in two siblings may suggest a role of NR0B1 in neuropsychological development or other still unknown underlying genetic defect.

Premature Pubarche due to Exogenous Testosterone Gel or Intense Diaper Rash Prevention Cream Use: A Case Series

BACKGROUND/AIMS

Premature pubarche is associated with conditions such as virilizing congenital adrenal hyperplasia, androgen-secreting tumors, and exogenous exposure to androgen products. We describe the clinical and hormonal features of a series of children who were referred to endocrine evaluation due to premature pubarche.

METHODS

This is a retrospective case series study of 14 children with premature pubarche and/or virilization. Five were unintentionally exposed to testosterone gel (parental use). Nine patients were intensely exposed to diaper rash prevention creams. Clinical and laboratory data were revised.

RESULTS

Moderate to severe virilization was detected in the 5 patients (2 boys and 3 girls) who were exposed to testosterone gel. These patients had pubic hair development associated with clitoromegaly (3/3), penile enlargement (2/2), and accelerated growth (5/5). Testosterone levels were elevated in 4/5 patients associated with normal prepubertal gonadotropin levels and adrenal androgen precursors. The 9 children who were intensely exposed to diaper rash prevention creams had mild pubarche (intermediate hair) without any other clinical manifestation of pubertal development. Three of them exhibited pubic hair thinning after cream withdrawal.

CONCLUSION

Unintentional topical androgen exposure or the intense use of diaper rash prevention cream should be ruled out in children with precocious pubarche and/or virilization signs to avoid misdiagnosis and expendable investigation.

Genetic investigation of patients with tall stature

CONTEXT

Patients with tall stature often remain undiagnosed after clinical investigation and few studies have genetically assessed this group, most of them without a systematic approach.

OBJECTIVE

To assess prospectively a group of individuals with tall stature, with and without syndromic features, and to establish a molecular diagnosis for their growth disorder.

DESIGN

Screening by karyotype (n = 42), chromosome microarray analyses (CMA) (n = 16), MS-MLPA (n = 2) targeted panel (n = 12) and whole-exome sequencing (n = 31).

PATIENTS AND METHODS

We selected 42 patients with tall stature after exclusion of pathologies in GH/IGF1 axis and divided them into syndromic (n = 30) and non-syndromic (n = 12) subgroups.

MAIN OUTCOME MEASURES

Frequencies of pathogenic findings.

RESULTS

We identified two patients with chromosomal abnormalities including SHOX trisomy by karyotype, one 9q22.3 microdeletion syndrome by CMA, two cases of Beckwith-Wiedemann syndrome by targeted MS-MLPA analysis and nine cases with heterozygous pathogenic or likely pathogenic genetic variants by multigene analysis techniques (FBN1 = 3, NSD1 = 2, NFIX = 1, SUZ12 = 1, CHD8 = 1, MC4R = 1). Three of 20 patients analyzed by WES had their diagnosis established. Only one non-syndromic patient had a definitive diagnosis. The sequential genetic assessment diagnosed 14 out of 42 (33.3%) tall patients.

CONCLUSION

A systematic molecular approach of patients with tall stature was able to identify the etiology in 13 out of 30 (43.3%) syndromic and 1 out of 12 (8.3%) non-syndromic patients, contributing to the genetic counseling and avoiding unfavorable outcomes in the syndromic subgroup.

Outcomes of Patients with Central Precocious Puberty Due to Loss-of-Function Mutations in the MKRN3 Gene after Treatment with Gonadotropin-Releasing Hormone Analog

INTRODUCTION

Loss-of-function mutation of MKRN3 represents the most frequent genetic cause of familial central precocious puberty (CPP). The outcomes of gonadotropin-releasing hormone analog (GnRHa) treatment in CPP patients with MKRN3 defects are unknown.

OBJECTIVE

To describe the clinical and hormonal features of patients with CPP with or without MKRN3 mutations after GnRHa treatment. Anthropometric, metabolic and reproductive parameters were evaluated.

PATIENTS AND METHODS

Twenty-nine female patients with CPP due to loss-of-function mutations in the MKRN3 and 43 female patients with idiopathic CPP were included. Their medical records were retrospectively evaluated for clinical, laboratory, and imaging study, before, during, and after GnRHa treatment. All patients with idiopathic CPP and 11 patients with CPP due to MKRN3 defects reached final height (FH).

RESULTS

At the diagnosis, there were no significant differences between clinical and laboratory features of patients with CPP with or without MKRN3 mutations. A high prevalence of overweight and obesity was observed in patients with CPP with or without MKRN3 mutations (47.3 and 50%, respectively), followed by a significant reduction after GnRHa treatment. No significant differences in the values of mean FH and target height were found between the 2 CPP groups after GnRHa treatment. Menarche occurred at the expected age in patients with or without CPP due to MKRN3 mutations (11.5 ± 1.3 and 12 ± 0.6 years, respectively). The prevalence of polycystic ovarian syndrome was 9.1% in patients with CPP due to MKRN3 mutations and 5.9% in those with idiopathic CPP.

CONCLUSION

Anthropometric, metabolic, and reproductive outcomes after GnRHa treatment were comparable in CPP patients, with or without MKRN3 mutations, suggesting the absence of deleterious effects of MKRN3 defects in young female adults' life.

Pioneering studies on monogenic central precocious puberty

Pubertal timing in humans is determined by complex interactions including hormonal, metabolic, environmental, ethnic, and genetic factors. Central precocious puberty (CPP) is defined as the premature reactivation of the hypothalamic-pituitary-gonadal axis, starting before the ages of 8 and 9 years in girls and boys, respectively; familial CPP is defined by the occurrence of CPP in two or more family members. Pioneering studies have evidenced the participation of genetic factors in pubertal timing, mainly identifying genetic causes of CPP in sporadic and familial cases. In this context, rare activating mutations were identified in genes of the kisspeptin excitatory pathway (KISS1R and KISS1 mutations). More recently, loss-of-function mutations in two imprinted genes (MKRN3 and DLK1) have been identified as important causes of familial CPP, describing novel players in the modulation of the hypothalamic-pituitary-gonadal axis in physiological and pathological conditions. MKRN3 mutations are the most common cause of familial CPP, and patients with MKRN3 mutations present clinical features indistinguishable from idiopathic CPP. Meanwhile, adult patients with DLK1 mutations present high frequency of metabolic alterations (overweight/obesity, early onset type 2 diabetes and hyperlipidemia), indicating that DLK1 may be a novel link between reproduction and metabolism. Arch Endocrinol Metab. 2019;63(4):438-44.

Spontaneous fertility in a male patient with testotoxicosis despite suppression of FSH levels

Testotoxicosis is a rare cause of peripheral precocious puberty in boys caused by constitutively activating mutations of the LHCG receptor. Affected males usually have normal gonadotropin profiles and fertility in their adult life. Here, we described the long-term follow-up of a 24-year-old young man with severe testotoxicosis due to a de novo activating mutation in the third transmembrane helix of the LHCGR (p.Leu457Arg). This patient was treated with different medications, including medroxyprogesterone acetate, ketoconazole, cyproterone acetate and aromatase inhibitor from age 2.5 to 9.5 years. His basal and GnRH-stimulated gonadotropin levels were continually suppressed during and after medical treatment. At adulthood, extremely high serum testosterone levels (>35 nmol/L), undetectable gonadotropin levels (LH < 0.15 IU/L and FSH < 0.6 IU/L) and oligozoospermia were evidenced. Despite his suppressed FSH levels and an unfavorable spermogram, the patient fathered a healthy girl and biological paternity was confirmed through analysis of microsatellites. Spontaneous fertility in a young man with severe testotoxicosis and chronic suppression of FSH levels reinforces the key role of high intratesticular testosterone levels in human spermatogenesis.

Assessment of stress levels in girls with central precocious puberty before and during long-acting gonadotropin-releasing hormone agonist treatment: a pilot study

BACKGROUND

The objective of the study was to determine the stress levels of girls with central precocious puberty (CPP) before and during treatment with a long-acting gonadotropin-releasing hormone agonist (GnRHa).

METHODS

The Child Stress Scale (CSS) was used for 10 unrelated girls with CPP before and after the first year of GnRHa treatment. The CSS is divided into four subscales (physical, psychological, psychological with depressive component and psychophysiological reactions). Through a quantitative analysis, it is possible to classify stress into four stages: alarm, resistance, near-exhaustion and exhaustion.

RESULTS

At diagnosis, 90% of the girls showed stress levels scores at the alarm or resistance stage on at least one subscale, mostly in terms of physical and psychological reactions. The mean total stress score was significantly higher before when compared to after GnRHa treatment (43.4±15.6 vs. 28.9±9.7; p<0.05). The mean stress scores obtained in all subscales, except the one on psychophysiological reactions, were significantly higher before GnRHa treatment.

CONCLUSIONS

Higher stress levels were a common finding in girls with CPP before treatment. The significant stress level reduction after pubertal suppression reinforces the idea that sexual precocity is a stressful condition in children. The CSS might be a useful tool for psychological assessment of patients with CPP.

Mutation analysis of NANOS3 in Brazilian women with primary ovarian failure

OBJECTIVES:

Primary ovarian failure is a rare disorder, and approximately 90% of cases are of unknown etiology. The aim of this study was to search for mutations in NANOS3, a gene that was recently related to the etiology of primary ovarian failure, in a group of Brazilian women.

METHODS:

We screened for NANOS3 DNA variants in 30 consecutive women who were previously diagnosed with primary ovarian failure, of unknown etiology and compared the results with those from 185 women with normal fertility. The NANOS3 gene was amplified by polymerase chain reaction using pairs of specific primers and then sequenced. The resulting sequences were compared with control sequences available in the National Center for Biotechnology and Information database.

RESULTS:

No mutations in NANOS3 were found in primary ovarian failure patients, but four previously described polymorphisms were identified at a similar frequency in the control and primary ovarian failure groups.

CONCLUSIONS:

Mutations in NANOS3 were not associated with primary ovarian failure in the present cohort.

Causes, diagnosis, and treatment of central precocious puberty

Central precocious puberty results from the premature activation of the hypothalamic-pituitary-gonadal axis. It mimics physiological pubertal development, although at an inappropriate chronological age (before 8 years in girls and 9 years in boys). It can be attributable to cerebral congenital malformations or acquired insults, but the cause in most cases in girls remains unknown. MKRN3 gene defects have been identified in familial disease, with important basic and clinical results. Indeed, genetic analysis of this gene should be included in the routine clinical investigation of familial and idiopathic cases of central precocious puberty. Gonadotropin-releasing hormone agonists are the gold-standard treatment. The assessment and management of this disease remain challenging for paediatric endocrinologists. In this Series paper, we describe current challenges involving the precise diagnosis and adequate treatment of this disorder.

Sexual Precocity--Genetic Bases of Central Precocious Puberty and Autonomous Gonadal Activation

Precocious puberty has been classically defined as the onset of sexual secondary characteristics in girls younger than 8 years and in boys younger than 9 years. The discovery of potential factors which trigger human puberty is one of the central mysteries of reproductive biology. Several approaches, including mutational analysis of candidate genes, large-scale genome-wide association studies, and (more recently) whole-exome sequencing, have been performed in attempt to identify novel genetic factors that modulate the human hypothalamic-pituitary-gonadal axis, resulting in premature sexual development. In the last two decades, it has been well established that autonomous gonadal activation can be caused by somatic (GNAS) or germline (LHCGR)-activating mutations of genes that encode essential elements for signal transduction of G protein-coupled receptors, resulting in peripheral precocious puberty in McCune-Albright syndrome and testotoxicosis, respectively. More recently, dominant activating and inactivating mutations of excitatory (KISS1/KISS1R) and inhibitory (MKRN3) modulators of gonadotropin-releasing hormone secretion, respectively, were associated with central precocious puberty phenotype. Indeed, loss-of-function mutations of MKRN3, a maternal imprinted gene located at chromosome 15q, currently represent a frequent cause of central precocious puberty diagnosed in families from distinct geographic origins. Here, we review the known genetic defects in central and peripheral precocious puberty.

[Advances in the etiology, diagnosis and treatment of central precocious puberty]

The onset of puberty is first detected as an increase in the amplitude and frequency of pulses of gonadotropin-releasing hormone (GnRH) after a quiescent period during childhood. The reemergence of pulsatile GnRH secretion leads to increases in the secretion of the gonadotropins, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) by the pituitary gland, and the consequent activation of gonadal function. Early activation of the hypothalamic-pituitary-gonadal axis results in gonadotropin-dependent precocious puberty, also known as central precocious puberty (CPP), which is clinically defined by the development of secondary sexual characteristics before the age of 8 years in girls and 9 years in boys. Pubertal timing is influenced by complex interactions among genetic, nutritional, environmental, and socioeconomic factors. CPP is diagnosed on the basis of clinical signs of progressive pubertal development before the age of 8 years in girls and 9 years in boys, pubertal basal and/or GnRH-stimulated LH levels, and advanced bone age. Magnetic resonance imaging of the central nervous system is essential for establishing the CPP form as organic or idiopathic. Depot GnRH-analogues represent the first-line of therapy in CPP. Very recently, the genetic component of CPP was demonstrated by the evidence that the deficiency of the MKRN3 gene, located on long arm of chromosome 15, causes familial CPP in humans. In this current review, clinical and therapeutic aspects of the CPP will be discussed, contributing to adequate diagnosis and criterious approach of this relevant condition of pediatric endocrinology.

Validation of an immunoassay for anti-Müllerian hormone measurements and reference intervals in healthy Brazilian subjects

Background

Anti-Müllerian hormone is marker of ovarian and testicular reserve. The clinical use of this hormone requires proper standardization of reference intervals. The aims of this study were to validate the Anti-Müllerian hormone Gen II immunoassay, to establish Anti-Müllerian hormone reference intervals in healthy subjects, and to evaluate the influence of hormonal contraceptives, smoking, and body mass index on Anti-Müllerian hormone.

Methods

The validation of the Anti-Müllerian hormone Gen II assay (Beckman Coulter Company, TX, USA) was performed using a simplified protocol recommended by Clinical Laboratory Standard Institute. One-hundred and thirty-three healthy females and 120 males were prospectively selected for this study.

Results

The analytical and functional sensitivities of the Anti-Müllerian hormone Gen II immunoassay were 0.02 and 0.2 ng/mL, respectively. Intra-assay coefficients ranged from 5.2 to 9.0%, whereas inter-assay precision ranged from 4.6 to 7.8% at different concentrations. In females, Anti-Müllerian hormone showed progressive decline with increasing age (r = −0.4, p < 0.001), whereas in males, age showed no influence on Anti-Müllerian hormone concentrations. In females, Anti-Müllerian hormone concentrations did not differ between users and non-users of hormonal contraceptives, smokers, and non-smokers and obese and lean individuals. However, there was a negative and significant correlation between Anti-Müllerian hormone and body mass index in males (r = −0.3, p = 0.008).

Conclusions

Anti-Müllerian hormone Gen II assay was reliable for determining serum Anti-Müllerian hormone concentrations. Anti-Müllerian hormone concentrations declined with aging and presented a wide inter-individual variability. The lack of influence of hormonal contraceptives, smoking, and obesity on Anti-Müllerian hormone in both sexes allowed us to refine the normative concentrations for the Brazilian population.

Molecular and gene network analysis of thyroid transcription factor 1 (TTF1) and enhanced at puberty (EAP1) genes in patients with GnRH-dependent pubertal disorders

BACKGROUND/AIM

TTF1 and EAP1 are transcription factors that modulate gonadotropin-releasing hormone expression. We investigated the contribution of TTF1 and EAP1 genes to central pubertal disorders.

PATIENTS AND METHODS

133 patients with central pubertal disorders were studied: 86 with central precocious puberty and 47 with normosmic isolated hypogonadotropic hypogonadism. The coding region of TTF1 and EAP1 were sequenced. Variations of polyglutamine and polyalanine repeats in EAP1 were analyzed by GeneScan software. Association of TTF1 and EAP1 to genes implicated in timing of puberty was investigated by meta-network framework GeneMANIA and Cytoscape software.

RESULTS

Direct sequencing of the TTF1 did not reveal any mutation or polymorphisms. Four EAP1 synonymous variants were identified with similar frequencies among groups. The most common EAP1 5'-distal polyalanine genotype was the homozygous 12/12, but the genotype 12/9 was identified in 2 central precocious puberty sisters without functional alteration in EAP1 transcriptional activity. TTF1 and EAP1 were connected, via genetic networks, to genes implicated in the control of menarche.

CONCLUSION

No TTF1 or EAP1 germline mutations were associated with central pubertal disorders. TTF1 and EAP1 may affect puberty by changing expression in response to other members of puberty-associated gene networks, or by differentially affecting the expression of gene components of these networks.

New causes of central precocious puberty: the role of genetic factors

A pivotal event in the onset of puberty in humans is the reemergence of the pulsatile release of the gonadotropin-releasing hormone (GnRH) from hypothalamic neurons. Pathways governing GnRH ontogeny and physiology have been discovered by studying animal models and humans with reproductive disorders. Recent human studies implicated the activation of kisspeptin and its cognate receptor (KISS1/KISS1R) and the inactivation of MKRN3 in the premature reactivation of GnRH secretion, causing central precocious puberty (CPP). MKRN3, an imprinted gene located on the long arm of chromosome 15, encodes makorin ring finger protein 3, which is involved in ubiquitination and cell signaling. The MKRN3 protein is derived only from RNA transcribed from the paternally inherited copy of the gene due to maternal imprinting. Currently, MKRN3 defects represent the most frequent known genetic cause of familial CPP. In this review, we explored the clinical, hormonal and genetic aspects of children with sporadic or familial CPP caused by mutations in the kisspeptin and MKRN3 systems, essential genetic factors for pubertal timing.

Polycystic ovary syndrome and obesity do not affect vascular parameters related to early atherosclerosis in young women without glucose metabolism disturbances, arterial hypertension and severe abnormalities of lipid profile

The aim of this study was to evaluate the influence of polycystic ovary syndrome (PCOS) and obesity on vascular parameters related to early atherosclerosis (VP-EA) [brachial flow-mediated dilation (FMD), carotid intima-media thickness (CIMT) and carotid arterial compliance (CAC)] in women with minor cardiovascular risk factors (CVRFs). Twenty-five young women with PCOS and 23 eumenorrheic women matched for body mass index (BMI) were studied. The women were subdivided according to BMI and PCOS status, and comparisons were done between PCOS and Control group, regardless of BMI, and between Obese and Lean group, regardless of the presence of PCOS. Insulin resistance was higher in PCOS-group than in control-group and in obese-group than in lean-group. The median of all VP-EA evaluated were similar between PCOS-group and Control-group [FMD: 6.6 versus 8.4% (p = NS); CIMT: 48.0 versus 47.0 mm.10-2 (p = NS); CAC: 6.2 versus 5.6N-1.m4.10-10 (p = NS)] and between obese-group and lean-group [FMD: 7.8 versus 6.6% (p = NS); CIMT: 48.0 versus 47.0 mm.10-2 (p = NS); CAC: 5.7 versus 6.3N-1.m4.10-10 (p = NS)]. These results suggest that PCOS and obesity do not affect VP-EA in women with minor CVRFs.

Early onset of primary hypogonadism revealed by serum anti-Müllerian hormone determination during infancy and childhood in trisomy 21

Male patients with an extra sex chromosome or autosome are expected to present primary hypogonadism at puberty owing to meiotic germ-cell failure. Scarce information is available on trisomy 21, a frequent autosomal aneuploidy. Our objective was to assess whether trisomy 21 presents with pubertal-onset, germ-cell specific, primary hypogonadism in males, or whether the hypogonadism is established earlier and affects other testicular cell populations. We assessed the functional status of the pituitary-testicular axis, especially Sertoli cell function, in 117 boys with trisomy 21 (ages: 2months-20year). To compare with an adequate control population, we established reference levels for serum anti-Müllerian hormone (AMH) in 421 normal males, from birth to adulthood, using a recently developed ultrasensitive assay. In trisomy 21, AMH was lower than normal, indicating Sertoli cell dysfunction, from early infancy, independently of the existence of cryptorchidism. The overall prevalence rate of AMH below the 3rd percentile was 64.3% in infants with trisomy 21. Follicle-stimulating hormone was elevated in patients <6months and after pubertal onset. Testosterone was within the normal range, but luteinizing hormone was elevated in most patients <6months and after pubertal onset, indicating a mild Leydig cell dysfunction. We conclude that in trisomy 21, primary hypogonadism involves a combined dysfunction of Sertoli and Leydig cells, which can be observed independently of cryptorchidism soon after birth, thus prompting the search for new hypotheses to explain the pathophysiology of gonadal dysfunction in autosomal trisomy.

Mutations of the KISS1 gene in disorders of puberty

CONTEXT

Kisspeptin, encoded by the KISS1 gene, is a key stimulatory factor of GnRH secretion and puberty onset. Inactivating mutations of its receptor (KISS1R) cause isolated hypogonadotropic hypogonadism (IHH). A unique KISS1R-activating mutation was described in central precocious puberty (CPP).

OBJECTIVE

Our objective was to investigate KISS1 mutations in patients with idiopathic CPP and normosmic IHH.

PATIENTS

Eighty-three children with CPP (77 girls) and 61 patients with IHH (40 men) were studied. The control group consisted of 200 individuals with normal pubertal development.

METHODS

The promoter region and the three exons of KISS1 were amplified and sequenced. Cells expressing KISS1R were stimulated with synthetic human wild-type or mutant kisspeptin-54 (kp54), and inositol phosphate accumulation was measured. In a second set of experiments, kp54 was preincubated in human serum before stimulation of the cells.

RESULTS

Two novel KISS1 missense mutations, p.P74S and p.H90D, were identified in three unrelated children with idiopathic CPP. Both mutations were absent in 400 control alleles. The p.P74S mutation was identified in the heterozygous state in a boy who developed CPP at 1 yr of age. The p.H90D mutation was identified in the homozygous state in two unrelated girls with CPP. In vitro studies revealed that the capacity of the P74S and H90D mutants to stimulate IP production was similar to the wild type. After preincubation of wild-type and mutant kp54 in human serum, the capacity to stimulate signal transduction was significantly greater for P74S compared with the wild type, suggesting that the p.P74S variant is more stable. Only polymorphisms were found in the IHH group.

CONCLUSION

Two KISS1 mutations were identified in unrelated patients with idiopathic CPP. The p.P74S variant was associated with higher kisspeptin resistance to degradation in comparison with the wild type, suggesting a role for this mutation in the precocious puberty phenotype.

Update on the etiology, diagnosis and therapeutic management of sexual precocity

Precocious puberty is defined as the development of secondary sexual characteristics before the age of 8 years in girls and 9 years in boys. Gonadotropin-dependent precocious puberty (GDPP) results from the premature activation of the hypothalamic-pituitary-gonadal axis and mimics the physiological pubertal development, although at an inadequate chronological age. Hormonal evaluation, mainly through basal and GnRH-stimulated LH levels shows activation of the gonadotropic axis. Gonadotropin-independent precocious puberty (GIPP) is the result of the secretion of sex steroids, independently from the activation of the gonadotropic axis. Several genetic causes, including constitutive activating mutations in the human LH-receptor gene and activating mutations in the Gs protein a-subunit gene are described as the etiology of testotoxicosis and McCune-Albright syndrome, respectively. The differential diagnosis between GDPP and GIPP has direct implications on the therapeutic option. Long-acting gonadotropin-releasing hormone (GnRH) analogs are the treatment of choice in GDPP. The treatment monitoring is carried out by clinical examination, hormonal evaluation measurements and image studies. For treatment of GIPP, drugs that act by blocking the action of sex steroids on their specific receptors (cyproterone, tamoxifen) or through their synthesis (ketoconazole, medroxyprogesterone, aromatase inhibitors) are used. In addition, variants of the normal pubertal development include isolated forms of precocious thelarche, precocious pubarche and precocious menarche. Here, we provide an update on the etiology, diagnosis and management of sexual precocity.

Long-term treatment of familial male-limited precocious puberty (testotoxicosis) with cyproterone acetate or ketoconazole

BACKGROUND

Familial male-limited precocious puberty (FMPP) or testotoxicosis is a rare gonadotrophin-independent form of sexual precocity caused by constitutively activating mutations of the LH receptor. Several clinical therapeutic approaches have been reported for this disorder, but with a paucity of long-term outcome data.

OBJECTIVE

To evaluate the long-term treatment of testotoxicosis with cyproterone acetate or ketoconazole.

DESIGN

A multicentric retrospective clinical study.

PATIENTS

Ten boys from eight unrelated Brazilian families who carried known LH-receptor activating mutations were treated with 70 mg/m(2) cyproterone acetate (n = 5) or 10 mg/kg ketoconazole (n = 5) for a mean period of 5 and 8 years, respectively.

MEASUREMENTS

Chronological and bone ages, bone age/chronological age ratio, target height (TH) range, adult height, basal and GnRH-stimulated gonadotrophin levels and basal testosterone levels were assessed.

RESULTS

Growth velocity decreased significantly during treatment with cyproterone acetate or ketoconazole when compared to pretreatment value in each group (P < 0.05). Bone age/chronological age ratio decreased significantly after cyproterone acetate or ketoconazole therapy. Basal testosterone levels were significantly lower in patients undergoing ketoconazole compared to cyproterone acetate treatment [0.6 +/- 0.3 nmol/l (42 +/- 21 ng/dl) vs. 5.6 +/- 4.0 nmol/l (392 +/- 280 ng/dl); P < 0.05], as expected. Secondary gonadotrophin-dependent precocious puberty occurred at a similar frequency (40%) in both groups. Five patients have attained adult height and two patients have already reached 90% of their adult height. Two of them achieved their TH range and one patient, for whom TH was not available, had an adult height of 0.3 SDS. Four boys (two in each group) did not attain their TH range.

CONCLUSION

Long-term treatment with cyproterone acetate or ketoconazole resulted in similar outcomes without important side-effects in boys with testotoxicosis. However, both therapies showed limited efficacy in attaining normal adult height.

Factors determining normal adult height in girls with gonadotropin-dependent precocious puberty treated with depot gonadotropin-releasing hormone analogs

CONTEXT

Several factors can affect adult height (AH) of patients with gonadotropin-dependent precocious puberty (GDPP) treated with depot GnRH analogs.

OBJECTIVE

Our objective was to determine factors influencing AH in patients with GDPP treated with depot GnRH analogs.

PATIENTS

A total of 54 patients (45 girls) with GDPP treated with depot GnRH analog who reached AH was included in the study.

DESIGN

Univariate and multivariate analyses of the factors potentially associated with AH were performed in all girls with GDPP. In addition, clinical features of the girls who attained target height (TH) range were compared with those who did not. Predicted height using Bayley and Pinneau tables was compared with attained AH.

RESULTS

In girls the mean AH was 155.3 +/- 6.9 cm (-1.2 +/- 1 sd) with TH range achieved by 81% of this group. Multiple regression analysis revealed that the interval between chronological age at onset of puberty and at the start of GnRH analog therapy, height sd scores (SDSs) at the start and end of therapy, and TH explained 74% of AH variance. The predicted height at interruption of GnRH therapy, obtained from Bayley and Pinneau tables for average bone age, was more accurate than for advanced bone age in both sexes. In boys the mean AH was 170.6 +/- 9.2 cm (-1 +/- 1.3 SDS), whereas TH was achieved by 89% of this group.

CONCLUSIONS

The major factors determining normal AH in girls with GDPP treated with depot GnRH analogs were shorter interval between the onset of puberty and start of therapy, higher height SDS at the start and end of therapy, and TH. Therefore, prompt depot GnRH analog therapy in properly selected patients with GDPP is critical to obtain normal AH.

A GPR54-activating mutation in a patient with central precocious puberty

Gonadotropin-dependent, or central, precocious puberty is caused by early maturation of the hypothalamic-pituitary-gonadal axis. In girls, this condition is most often idiopathic. Recently, a G protein-coupled receptor, GPR54, and its ligand, kisspeptin, were described as an excitatory neuroregulator system for the secretion of gonadotropin-releasing hormone (GnRH). In this study, we have identified an autosomal dominant GPR54 mutation--the substitution of proline for arginine at codon 386 (Arg386Pro)--in an adopted girl with idiopathic central precocious puberty (whose biologic family was not available for genetic studies). In vitro studies have shown that this mutation leads to prolonged activation of intracellular signaling pathways in response to kisspeptin. The Arg386Pro mutant appears to be associated with central precocious puberty.

Allelic variants of the gamma-aminobutyric acid-A receptor alpha1-subunit gene (GABRA1) are not associated with idiopathic gonadotropin-dependent precocious puberty in girls with and without electroencephalographic abnormalities

CONTEXT

gamma-Aminobutyric acid (GABA) is a dominant inhibitory neurotransmitter involved in the modulation of brain electric activity and puberty onset in primates. GABA inhibitory effects on GnRH neurons are mainly mediated by GABA-A receptor alpha1-subunit.

OBJECTIVE

The objective of this study was to investigate functional mutations or polymorphisms of the GABA-A receptor alpha1-subunit gene (GABRA1) in girls with idiopathic gonadotropin-dependent precocious puberty (GDPP) with and without electroencephalographic (EEG) abnormalities.

DESIGN

The entire coding region of GABRA1 was sequenced in all patients. Two known GABRA1 polymorphisms were investigated by GeneScan software analysis or enzymatic restriction. Seventy-three normal women were used as controls for genetic study. EEG tracings were recorded in 23 girls with GDPP and 17 girls with adequate pubertal development.

SETTING

The study was performed at a university hospital.

PATIENTS

Thirty-one girls from 28 unrelated families with idiopathic GDPP were studied.

RESULTS

Automatic sequencing revealed no functional mutations in girls with GDPP. Seven different GABRA1 polymorphisms, including two exonic (156T>C and 1323G>A) and five intronic [IVS2-712(GT)n, IVS3+12A>T, IVS8+45T>G, IVS9+76A>G, and IVS10+15G>A], were found in GDPP girls and controls. Abnormal EEG tracings were found in 26% of 23 girls with GDPP, two of them with epilepsy. The genotype and allele frequencies of the GABRA1 polymorphisms were not statistically different between unrelated GDPP girls and controls or between GDPP girls with or without EEG abnormalities.

CONCLUSIONS

GABRA1 functional mutations or polymorphisms are not associated with the intrinsic mechanism of GDPP in girls with and without EEG abnormalities.

Preclinical diagnosis of testotoxicosis in a boy with an activating mutation of the luteinizing hormone receptor

BACKGROUND

Testotoxicosis is an autosomal dominant disorder usually recognized by progressive virilization, linear growth acceleration, skeletal maturation and pubertal testosterone levels in boys before 4 years of age.

OBJECTIVE

To describe the clinical and hormonal follow-up of a male infant with testotoxicosis who was initially diagnosed by molecular analysis.

PATIENT

A healthy asymptomatic 10 month-old boy was referred to the endocrinologist because his older brother had diagnosis of familial testotoxicosis due to the activating mutation Thr577Ile of the luteinizing hormone (LH) receptor.

RESULTS

Automatic sequencing of exon 11 of the LH receptor gene revealed the same heterozygous Thr577Ile mutation in the asymptomatic boy. He had no signs of virilization or accelerated growth. His bone age was delayed. Serum LH and follicle stimulating hormone (FSH) concentrations were in the prepubertal range, testosterone levels were slightly elevated (31 ng/dl [1.07 nmol/l]). In the following 6 months, his testosterone levels progressively increased, achieving higher levels (146 ng/dl [5 nmol/l]) without testicular enlargement or pubic hair development. Despite the lack of virilization signs, an anti-androgen was started due to the increase in testosterone levels and growth velocity at the age of 1.3 years.

CONCLUSION

We describe the preclinical diagnosis of testotoxicosis in a boy by DNA analysis. Very early diagnosis in affected families can result in prompt treatment, and reduce the deleterious consequences of premature puberty in boys with this rare monogenic disorder.

Clinical and hormonal features of selective follicle-stimulating hormone (FSH) deficiency due to FSH beta-subunit gene mutations in both sexes

OBJECTIVE

To report the clinical, hormonal, and molecular features of a female adolescent with selective FSH deficiency. In addition, a complete review of previous cases is provided, focusing on hormonal aspects.

DESIGN

Clinical study.

SETTING

University hospital.

PATIENT(S)

A 16-year-old girl with primary amenorrhea and poor breast development due to isolated FSH deficiency.

INTERVENTION(S)

Blood drawing before and after GnRH stimulation and pelvic ultrasound examination.

MAIN OUTCOME MEASURE(S)

Gonadotropin and E(2) measurements and sequencing of the FSH beta-subunit gene.

RESULT(S)

The patient was referred for primary amenorrhea and partial breast development (Tanner III). Her basal and GnRH-stimulated LH levels were elevated (31 IU/L and 98 IU/L, respectively), whereas her FSH levels were undetectable (<1 IU/L) in both conditions. Estradiol levels were low (<13 pg/mL). Automatic sequencing showed a nucleotide substitution of C for A in exon 3, resulting in a homozygous nonsense mutation in amino acid position 76 (Tyr76X) of the FSH beta-subunit.

CONCLUSION(S)

The Tyr76X mutation of the FSH beta-subunit was associated with a partial phenotype of FSH deficiency. To date, only four loss-of-function mutations of the FSH beta-subunit have been described in eight patients with undetectable serum FSH and high serum LH levels. Therefore, this unusual hormonal profile strongly suggests a defect in the FSH beta-subunit in both sexes.

Thymus invasion and atrophy induced by Paracoccidioides brasiliensis in BALB/c mice

Literature has shown that immunosuppression observed in systemic mycosis can be related to damage in primary lymphoid organs. We have studied the immunopathological alterations induced experimentally by Paracoccidioides brasiliensis in these organs. In this work, thymic alterations induced in BALB/c mice during acute and chronic stages of infection are described. It was observed that P. brasiliensis is able to invade the thymic microenvironment, inducing severe atrophy characterized by degeneration of the cortical area, organ weight decrease, loss of corticomedullary delimitation and increase in histiocyte number. Occurrence of polymorphonuclear infiltration in the subcapsular area was also observed. Our results demonstrate that P. brasiliensis induces profound thymic atrophy and raises the question of whether this could be a fungal strategy to achieve successful establishment in the host over the long term.

Adrenocorticotropin-dependent precocious puberty of testicular origin in a boy with X-linked adrenal hypoplasia congenita due to a novel mutation in the DAX1 gene

Primary adrenal insufficiency is a rare condition in pediatric age, and its association with precocious sexual development is very uncommon. We report a 2-yr-old Brazilian boy with DAX1 gene mutation whose first clinical manifestation was isosexual gonadotropin-independent precocious puberty. He presented with pubic hair, enlarged penis and testes, and advanced bone age. T levels were elevated, whereas basal and GnRH-stimulated LH levels were compatible with a prepubertal pattern. Chronic GnRH agonist therapy did not reduce T levels, supporting the diagnosis of gonadotropin-independent precocious puberty. Testotoxicosis was ruled out after normal sequencing of exon 11 of the LH receptor gene. At age 3 yr he developed clinical and hormonal features of severe primary adrenal insufficiency. The entire coding region of the DAX1 gene was analyzed through direct sequencing. A nucleotide G insertion between nucleotides 430 and 431 in exon 1, resulting in a novel frameshift mutation and a premature stop codon at position 71 of DAX-1, was identified. Surprisingly, steroid replacement therapy induced a clear decrease in testicular size and T levels to the prepubertal range. These findings suggest that chronic excessive ACTH levels resulting from adrenal insufficiency may stimulate Leydig cells and lead to gonadotropin-independent precocious puberty in some boys with DAX1 gene mutations.

The effect of distinct activating mutations of the luteinizing hormone receptor gene on the pituitary-gonadal axis in both sexes

OBJECTIVE

Familial or sporadic male-limited precocious puberty is a distinct and unusual gonadotrophin-independent form of sexual precocity caused by constitutively activating mutations of the luteinizing hormone receptor (LHR). In the present study, we evaluated the effect of known activating mutations at different sites of the LHR gene on the pituitary-gonadal axis in both sexes.

PATIENTS

Four unrelated Brazilian boys (I-IV) with gonadotrophin-independent precocious puberty and two asymptomatic females (V-VI), a sister and mother of two of the affected boys, were studied. Patients I, II and V carried the Ala568Val mutation located at the third intracellular loop of the LHR. Patient III carried the Leu457Arg mutation at the third transmembrane helix, and patients IV and VI carried the Thr577Ile mutation at the sixth transmembrane helix of the LHR.

MEASUREMENTS

Serum levels of LH, FSH, testosterone, and oestradiol under basal and GnRH-stimulated conditions were determined in all patients. Testosterone levels were also measured after a hCG stimulation test in patient III.

RESULTS

Basal LH and FSH levels were prepubertal in all boys studied. The GnRH-stimulated serum LH and FSH levels were prepubertal in three boys (I, II and IV), whereas patient III showed totally suppressed LH and FSH levels at ages 2 and 7 years (bone ages 6 and 14 years, respectively). Serum testosterone levels ranged from 3.8 to 69.5 nmol/l in the four boys. Patient III had the highest testosterone levels that did not respond to hCG stimulation. The 4 year-old girl (patient V) was phenotypically normal and the acute response to GnRH was indicative of prepubertal status. Patient VI had normal menstrual cycles and fertility.

CONCLUSIONS

These findings indicate variable effects of LHR activating mutations on the pituitary-gonadal axis in boys that can result in lack of normal LH and FSH release. In contrast, prepubertal and adult females were asymptomatic and had normal basal and GnRH-stimulated LH and FSH levels.

Diagnostic value of fluorometric assays in the evaluation of precocious puberty

To establish normative data and determine the value of fluorometric AutoDELFIA assays (Wallac Oy) in the investigation of precocious puberty, we determined serum levels of LH, FSH, testosterone, and estradiol under basal and GnRH-stimulated conditions in 277 normal subjects at various pubertal stages and in 77 patients with precocious puberty. A substantial overlap was observed in basal and GnRH-stimulated gonadotropin levels in normal individuals of both sexes with pubertal Tanner stages 1 and 2. The 95th percentile of the normal prepubertal population was the cut-off limit between prepubertal and pubertal levels. These limits were 0.6 IU/L in both sexes for basal LH, 9.6 IU/L in boys and 6.9 IU/L in girls for peak LH after GnRH stimulation, 19 ng/dL in boys for basal testosterone, and 13.6 pg/mL in girls for basal estradiol. Basal and peak LH exceeding these limits were considered positive tests for the diagnosis of gonadotropin-dependent precocious puberty. According to these criteria, the sensitivities of basal and peak LH for the latter diagnosis were 71.4% and 100% in boys, and 62.7% and 92.2% in girls. The specificity and positive predicted value were 100% in both sexes for basal and peak LH levels. The negative predicted values for basal and peak LH were 62.5% and 100% in boys, and 40.6% and 76.5% in girls. Basal and GnRH-stimulated FSH levels overlapped among the various pubertal stages in normal subjects and were, in general, not helpful in the differential diagnosis of precocious puberty. In conclusion, basal LH levels were sufficient to establish the diagnosis of gonadotropin-dependent precocious puberty in 71.4% of boys and 62.7% of girls. In the remaining patients, a GnRH stimulation test was still necessary to confirm this diagnosis. Finally, suppressed LH and FSH levels after GnRH stimulation indicate gonadotropin-independent sexual steroid production.

A unique constitutively activating mutation in third transmembrane helix of luteinizing hormone receptor causes sporadic male gonadotropin-independent precocious puberty

Several constitutively activating mutations have been demonstrated in the sixth transmembrane helix of the human LH receptor (hLHR) in boys with gonadotropin-independent precocious puberty. In the current study, we examined two unrelated Brazilian boys with gonadotropin-independent precocious puberty caused by two different heterozygous activating mutations of the hLHR. Direct sequencing of the entire exon 11 of the hLHR revealed a heterozygous substitution of T for G at nucleotide 1370, that converts Leu 457 to Arg in the third transmembrane helix of the hLHR in one affected boy. His biological parents had a normal hLHR gene sequence, establishing the sporadic nature of this novel Leu457Arg mutation. Human embryonic 293 cells expressing hLHR mutant (L457R) or hLHR wild-type bound CG with high affinity. However, cells expressing hLHR(L457R) exhibited significantly higher basal levels of cAMP (7- to 14-fold) than cells expressing the wild-type receptor, indicating constitutive activation of hLHR(L457R). Basal levels of cAMP in hLHR(L457R)-expressing cells were, nonetheless, not as great as the levels of cAMP produced by hLHR wild-type-expressing cells incubated with a saturating concentration of CG. Furthermore, cells expressing hLHR(L457R) were unresponsive to further stimulation by CG. This finding was confirmed in the patient by lack of an increase in serum testosterone after CG stimulation. These results suggest that the conformation of hLHR(L457R) mutant represents a different activated receptor state (R*) than the agonist-occupied wild-type receptor. We also identified the previously described Ala568Val mutation in the third intracellular loop of the LHR in the other affected African-Brazilian boy and his normal prepubertal sister, suggesting the inherited form of precocious puberty in this boy. We conclude that the third transmembrane helix is a potential area for activating mutations of the hLHR that cause male precocious puberty.