Malignant testicular germ cell tumors in postpubertal individuals with androgen insensitivity: prevalence, pathology and relevance of single nucleotide polymorphism-based susceptibility profiling

STUDY QUESTION

What is the prevalence of malignant testicular germ cell tumors (TGCT) and its precursors, (pre-) germ cell neoplasia in situ (GCNIS), in late teenagers and adults who have androgen insensitivity syndrome (AIS) and the impact of an individual's genetic susceptibility to development of TGCT?

SUMMARY ANSWER

No GCNIS or TGCT was diagnosed, but pre-GCNIS was identified in 14 and 10% of complete and partial AIS patients, respectively, and was associated with a higher genetic susceptibility score (GSS), with special attention for KITLG (rs995030) and ATFZIP (rs2900333).

WHAT IS KNOWN ALREADY

Many adult women with AIS decline prophylactic gonadectomy, while data regarding the incidence, pathophysiology and outcomes of TGCT in postpubertal individuals with AIS are lacking. The relevance of genetic factors, such as single nucleotide polymorphisms (SNPs), in predisposing AIS individuals to TGCT is unknown.

STUDY DESIGN, SIZE, DURATION

This multicenter collaborative study on prophylactically removed gonadal tissue was conducted in a pathology lab specialized in germ cell tumor biology.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Material from 52 postpubertal individuals with molecularly confirmed AIS (97 gonadal samples) was included; the median age at surgery was 17.5 (14-54) years. Immunohistochemical studies and high-throughput profiling of 14 TGCT-associated SNPs were performed. The main outcome measures were the prevalence of pre-GCNIS, GCNIS and TGCT, and its correlation with a GSS, developed based on the results of recent genome-wide association studies.

MAIN RESULTS AND ROLE OF CHANCE

The earliest recognizable change preceding GCNIS, referred to as pre-GCNIS, was present in 14% of individuals with complete and 10% of those with partial AIS at a median age of 16 years. No GCNIS or invasive TGCT were found. The median GSS was significantly greater for those with, compared to those without, pre-GCNIS (P = 0.01), with an overlap between groups. Our data suggest important roles for risk alleles G at KITLG (rs995030) and C at ATFZIP (rs2900333), among the 14 studied TGCT-associated SNPs.

LARGE SCALE DATA

N/A.

LIMITATIONS REASONS FOR CAUTION

A limited number of cases were included.

WIDER IMPLICATIONS OF THE FINDINGS

Our data suggest that the prevalence of pre-GCNIS in individuals with AIS beyond puberty is around 15%. Genetic susceptibility likely contributes to pre-GCNIS development in AIS but factors related to malignant progression remain unclear. Although data in older patients remain scarce, malignant progression appears to be a rare event, although the natural history of the premalignant lesion remains unknown. Therefore, the practice of routine prophylactic gonadectomy in adults with AIS appears questionable and the patient's preference, after having been fully informed, should be decisive in this matter.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by research grants from the Research Foundation Flanders (FWO) (to M.C.), the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq G0D6713N) (to B.B.M. and M.C.) and the European Society for Pediatric Endocrinology (ESPE), granted by Novo Nordisk AB (to J.K.). There are no competing interests.

Identification of an AR Mutation-Negative Class of Androgen Insensitivity by Determining Endogenous AR Activity

CONTEXT

Only approximately 85% of patients with a clinical diagnosis complete androgen insensitivity syndrome and less than 30% with partial androgen insensitivity syndrome can be explained by inactivating mutations in the androgen receptor (AR) gene.

OBJECTIVE

The objective of the study was to clarify this discrepancy by in vitro determination of AR transcriptional activity in individuals with disorders of sex development (DSD) and male controls.

DESIGN

Quantification of DHT-dependent transcriptional induction of the AR target gene apolipoprotein D (APOD) in cultured genital fibroblasts (GFs) (APOD assay) and next-generation sequencing of the complete coding and noncoding AR locus.

SETTING

The study was conducted at a university hospital endocrine research laboratory.

PATIENTS

GFs from 169 individuals were studied encompassing control males (n = 68), molecular defined DSD other than androgen insensitivity syndrome (AIS; n = 18), AR mutation-positive AIS (n = 37), and previously undiagnosed DSD including patients with a clinical suspicion of AIS (n = 46).

INTERVENTION(S)

There were no interventions.

MAIN OUTCOME MEASURE(S)

DHT-dependent APOD expression in cultured GF and AR mutation status in 169 individuals was measured.

RESULTS

The APOD assay clearly separated control individuals (healthy males and molecular defined DSD patients other than AIS) from genetically proven AIS (cutoff < 2.3-fold APOD-induction; 100% sensitivity, 93.3% specificity, P < .0001). Of 46 DSD individuals with no AR mutation, 17 (37%) fell below the cutoff, indicating disrupted androgen signaling.

CONCLUSIONS

AR mutation-positive AIS can be reliably identified by the APOD assay. Its combination with next-generation sequencing of the AR locus uncovered an AR mutation-negative, new class of androgen resistance, which we propose to name AIS type II. Our data support the existence of cellular components outside the AR affecting androgen signaling during sexual differentiation with high clinical relevance.

45,X/46,X,psu dic(Y) gonadal dysgenesis: influence of the two cell lines on the clinical phenotype, including gonadal histology

A child born with ambiguous genitalia (Prader III) was found to have a 45,X[92.2%]/46,X,psu dic(Y)(p12)[7.8%] karyotype in peripheral blood lymphocytes. The testosterone level was consistent with that of a normal male; however, gonadotropins were elevated. Ultrasound and endoscopy of the urogenital sinus revealed well-developed Müllerian structures. At 3.5 months, the child was operated for right-sided incarcerated hernia, and the gonad situated at the inguinal region was biopsied and classified as primitive testis. Based on the presence of Müllerian structures, anatomy of external genitalia and wish of the parents, the child was assigned female gender. She underwent removal of the left gonad at 4 months during another acute surgery; histology was similar to the right gonad. The rest of the right gonad was removed at 16 months, and feminizing genitoplasty took place at 3 years. The right and left gonad contained 28 and 22% of cells with a Y chromosome, respectively. During further histological examination, dysgenetic features of the gonads were discovered. Some germ cells displayed abnormal development based on the specific expression of immunohistochemical markers (OCT3/4, TSPY, KITLG), indicating a possible risk for future malignant germ cell tumor development. Contribution of the 45,X cell line to the phenotype was also observed: the patient developed celiac disease, and her growth pattern resembled that of Turner syndrome responding to growth hormone treatment.

Fertility of tall girls treated with high-dose estrogen, a dose-response relationship

CONTEXT

High-dose estrogen treatment to reduce final height of tall girls increases their risk for infertility in later life.

OBJECTIVE

The aim was to study the effect of estrogen dose on fertility outcome of these women.

DESIGN/SETTING

We conducted a retrospective cohort study of university hospital patients.

PATIENTS

We studied 125 tall women aged 20-42 yr, of whom 52 women had been treated with 100 μg and 43 with 200 μg of ethinyl estradiol (EE) in adolescence.

MAIN OUTCOMES

Time to first pregnancy, treatment for infertility, and live birth rate were measured.

RESULTS

The time to first pregnancy was increased in treated women. Of untreated women, 80% conceived within 1 yr vs. 69% of women treated with 100 μg EE and 59% of women treated with 200 μg EE. This trend of increased time to pregnancy with increasing estrogen dose was significant (log rank trend test, P = 0.01). Compared with untreated women, fecundability was reduced in women treated with both 100 μg EE [hazard ratio = 0.42; 95% confidence interval (CI), 0.19-0.95] and 200 μg EE (hazard ratio = 0.30; 95% CI, 0.13-0.72). We also observed a significant trend in the incidence of treatment for infertility with increased estrogen dose (P = 0.04). Fecundity was affected in women treated with 200 μg EE who had reduced odds of achieving at least one live birth (odds ratio = 0.13; 95% CI, 0.02-0.81), but not in women treated with 100 μg EE.

CONCLUSIONS

We report a dose-response relationship between fertility in later life and estrogen dose used for the treatment of tall stature in adolescent girls; a higher estrogen dose is associated with increased infertility.

A novel AMH missense mutation in a patient with persistent Müllerian duct syndrome

Persistent Müllerian duct syndrome (PMDS) is characterized by the presence of a uterus, fallopian tubes, and the upper part of the vagina in phenotypic normal male patients. Here, we report a patient diagnosed with PMDS with a novel homozygous missense mutation in the anti-Müllerian hormone (AMH) gene (single nucleotide insertion (C) at position 208 (c.208dup, p.Leu70fs)) leading to a frameshift and the introduction of a premature stop codon. Biopsy of both gonads revealed that germ cells were present in an irregular distribution. However, the absence of OCT3/4, PLAP and c-KIT expression indicated physiological maturation.

Genetic variation in candidate genes like the HMGA2 gene in the extremely tall

BACKGROUND/AIMS

Genetic variation in several candidate genes has been associated with short stature. Recently, a high-mobility group A2 (HMGA2) gene SNP has been robustly associated with height in the general population. Only few have attempted to study these genes in extremely tall stature. We therefore studied common genetic variation in candidate genes for height in extremely tall Dutch.

METHODS

We included 116 constitutionally tall cases with height >2 SD and 103 controls with normally distributed height <2 SD. We genotyped 10 common polymorphisms previously associated with height variation.

RESULTS

The HMGA2 gene SNP was significantly associated with tall stature. Using a logistic regression model, we calculated that carrying the HMGA2 (rs1042725) C allele significantly increased the odds of being tall (OR = 1.53, 95% CI 1.02-2.28; p = 0.03). In addition, controls with one or two copies of the C allele were significantly taller than controls carrying the TT genotype [TC: mean (SD) +0.61 (0.21) SDS; p = 0.004, and CC: +0.77 (0.25) SDS; p = 0.003].

CONCLUSION

Our study shows that a common polymorphism in the HMGA2 gene is not only associated with height variation in the general population but also plays an important role in one of the extremes of the height distribution.

Pubertal androgenization and gonadal histology in two 46,XY adolescents with NR5A1 mutations and predominantly female phenotype at birth

OBJECTIVE

Most patients with NR5A1 (SF-1) mutations and poor virilization at birth are sex-assigned female and receive early gonadectomy. Although studies in pituitary-specific Sf-1 knockout mice suggest hypogonadotropic hypogonadism, little is known about endocrine function at puberty and on germ cell tumor risk in patients with SF-1 mutations. This study reports on the natural course during puberty and on gonadal histology in two adolescents with SF-1 mutations and predominantly female phenotype at birth.

DESIGN AND METHODS

Clinical and hormonal data and histopathological studies are reported in one male and one female adolescent with, respectively, a nonsense mutation (c.9T>A, p.Tyr3X) and a deletion of the first two coding exons (NCBI36/hg18 Chr9:g.(126306276-126307705)_(126303229-126302828)del) of NR5A1, both predicted to fully disrupt gene function.

RESULTS

LH and testosterone concentrations were in the normal male range, virilization was disproportionate to the neonatal phenotype. In the girl, gonadectomy at 13 years revealed incomplete spermatogenesis and bilateral precursor lesions of testicular carcinoma in situ. In the boy, at the age of 12, numerous germ cells without signs of malignancy were present in bilateral testicular biopsy specimen.

CONCLUSIONS

In SF-1 mutations, the neonatal phenotype poorly predicts virilization at puberty. Even in poorly virilized cases at birth, male gender assignment may allow spontaneous puberty without signs of hypogonadotropic hypogonadism, and possibly fertility. Patients with SF-1 mutations are at increased risk for malignant germ cell tumors. In case of preserved gonads, early orchidopexy and germ cell tumor screening is warranted. The finding of premalignant and/or malignant changes should prompt gonadectomy or possibly irradiation.

Common polymorphisms in the GH/IGF-1 axis contribute to growth in extremely tall subjects

CONTEXT/OBJECTIVE

The growth hormone (GH)/insulin-like growth factor-1(IGF-1) axis is the key regulator of somatic growth in humans and its genes are plausible candidates to study the genetics of height variation. Here, we studied polymorphic variation in the GH/IGF-1 axis in the extremely tall Dutch.

METHODS

Case-control study of 166 tall cases with height >2 SDS and 206 controls with normally distributed height <2 SDS. Excluded were subjects with endocrine disorders or growth syndromes. We analyzed genomic DNA at 7 common polymorphisms in the GH-1, GH receptor (GHR), IGF-1 and IGFBP-3 genes.

RESULTS

The association of the GH-1 1663 SNP with tall stature approached statistical significance, with the T-allele more present in the tall (allele frequency (AF): 0.44 vs. 0.36; p=0.084). Moreover, haplotype frequencies at this locus were significantly different between cases and controls, with the GGT haplotype most commonly seen in cases (p=0.01). Allele frequencies of GHR polymorphisms were not different. For the IGF-1 CA-repeat we observed a higher frequency of homozygous 192-bp carriers among tall males compared to control males (AF: 0.62 vs. 0.55; p=0.02). The IGFBP-3 -202 C-allele occurred more frequently in cases than in controls (AF: 0.58 vs. 0.50; p=0.002). Within cases, those carrying one or two copies of the -202 C-allele were significantly taller than AA genotype carriers (AC, p=0.028 and CC, p=0.009). Serum IGFBP-3 levels were highest in AA genotype carriers, the -202 SNP explained 5.8% of the variation.

CONCLUSION

Polymorphic variation in the GH-1, IGF-1 and IGFBP-3 genes is associated with extremely tall stature. In particular, the IGFBP-3 -202 SNP is associated not only with being very tall but also with height variation within the tall.

Gonadal development and tumor formation at the crossroads of male and female sex determination

Malignant germ cell tumor (GCT) formation is a well-known complication in the management of patients with a disorder of sex development (DSD). DSDs are defined as congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical. DSD patients in whom the karyotype - at least at the gonadal level - contains (a part of) the Y chromosome are at increased risk for neoplastic transformation of germ cells, leading to the development of the so-called 'type II germ cell tumors'. However, tumor risk in the various forms of DSD varies considerably between the different diagnostic groups. This contribution integrates our actual knowledge on the pathophysiology of tumor development in DSDs, recent findings on gonadal (mal)development in DSD patients, and possible correlations between the patient's phenotype and his/her risk for germ cell tumor development.

Gonadal pathology and tumor risk in relation to clinical characteristics in patients with 45,X/46,XY mosaicism

CONTEXT

Gonadectomy is avoided whenever possible in boys with 45,X/46,XY. However, no clinical markers are currently available to guide clinicians in predicting gonadal tumor risk or hormone production.

OBJECTIVE

The objective of the study was to test the hypothesis that gonadal histology and risk for development of a malignant germ cell tumor are reflected by the clinical presentation of a 45,X/46,XY individual.

DESIGN

The design of the study was the correlation of clinical data [external masculinization score (EMS), pubertal outcome] with pathology data (gonadal phenotype, tumor risk).

SETTING

This was a multicenter study involving two multidisciplinary disorder of sex development teams.

PATIENTS

Patients included genetically proven 45,X/46,XY (and variants) cases, of whom at least one gonadal biopsy or gonadectomy specimen was available, together with clinical details.

INTERVENTIONS

Patients (n = 48) were divided into three groups, based on the EMS. Gonadal histology and tumor risk were assessed on paraffin-embedded samples (n = 87) by morphology and immunohistochemistry on the basis of established criteria.

MAIN OUTCOME MEASURES

Gonadal differentiation and tumor risk in the three clinical groups were measured. Clinical outcome in patients with at least one preserved gonad was also measured.

RESULTS

Tumor risk in the three groups was significantly related to the gonadal differentiation pattern (P < 0.001). In boys, hormone production was sufficient and was not predicted by the EMS.

CONCLUSIONS

The EMS reflects gonadal differentiation and tumor risk in patients with 45,X/46,XY. In boys, testosterone production is often sufficient, but strict follow-up is warranted because of malignancy risk, which appears inversely related to EMS. In girls, tumor risk is limited but gonads are not functional, making gonadectomy the most reasonable option.

Partial deletion of the NR5A1 (SF1) gene detected by synthetic probe MLPA in a patient with XY gonadal disorder of sex development

Steroidogenic factor 1 (SF1, officially NR5A1) is a nuclear receptor involved in adrenal and gonadal development. NR5A1 mutations have been identified in patients with various forms of 46,XY disorders of sex development (DSD), including complete gonadal dysgenesis with or without adrenal insufficiency, mild testicular dysgenesis with ambiguous external genitalia or female external genitalia with clitoromegaly, and penoscrotal hypospadias. We developed a synthetic probe set for MLPA analysis of the NR5A1 gene covering its 7 exons and analyzed 20 patients with 46,XY gonadal DSD in whom analyses failed to identify a genetic cause. We identified a partial NR5A1 deletion affecting exons 2 and 3, leading to NR5A1 haploinsufficiency in 1 patient presenting with female external genitalia with clitoromegaly, absence of a uterus, and mildly dysgenetic testes. This is the first partial NR5A1 gene deletion identified by MLPA in a patient with 46,XY gonadal DSD. This finding stresses the importance of investigating copy number changes, even at the exon level, in genes involved in gonadal DSD. As NR5A1 mutations can cause a wide spectrum of DSD with relatively high frequency, the analysis of the NR5A1 gene by MLPA is quite important and should be extended to larger groups of patients.

Fertility and ovarian function in high-dose estrogen-treated tall women

BACKGROUND/OBJECTIVE

High-dose estrogen treatment to reduce final height of tall girls has been shown to interfere with fertility. Ovarian function has not been studied. We therefore evaluated fertility and ovarian function in tall women who did or did not receive such treatment in adolescence.

METHODS

This was a retrospective cohort study of 413 tall women aged 23-48 yr, of whom 239 women had been treated. A separate group of 126 fertile, normoovulatory volunteers aged 22-47 yr served as controls.

RESULTS

Fertility was assessed in 285 tall women (157 treated, 128 untreated) who had attempted to conceive. After adjustment for age, treated women were at increased risk of experiencing subfertility [odds ratio (OR) 2.29, 95% confidence interval (CI) 1.38-3.81] and receiving infertility treatments (OR 3.44, 95% CI 1.76-6.73). Moreover, fecundity was notably affected because treated women had significantly reduced odds of achieving at least one live birth (OR 0.26, 95% CI 0.13-0.52). Remarkably, duration of treatment was correlated with time to pregnancy (r = 0.23, P = 0.008). Ovarian function was assessed in 174 tall women (119 treated, 55 untreated). Thirty-nine women (23%) exhibited a hypergonadotropic profile. After adjusting for age category, treated women had significantly higher odds of being diagnosed with imminent ovarian failure (OR 2.83, 95% CI 1.04-7.68). Serum FSH levels in these women were significantly increased, whereas antral follicle counts and serum anti-Müllerian hormone levels were decreased.

CONCLUSION

High-dose estrogen-treated tall women are at risk of subfertility in later life. Their fecundity is significantly reduced. Treated women exhibit signs of accelerated ovarian aging with concomitant follicle pool depletion, which may be the basis of the observed subfertility.

Fatherhood in tall men treated with high-dose sex steroids during adolescence

BACKGROUND/OBJECTIVE

Sex steroid treatment to reduce final height of tall boys has been available since the 1950s. In women, it has been shown to interfere with fertility. In men, no such data are available. We therefore evaluated fertility and gonadal function in tall men who did or did not receive high-dose androgen treatment in adolescence.

METHODS

We conducted a retrospective cohort study of 116 tall men, of whom 60 had been treated. Reproductive and gonadal function was assessed by standardized interview, semen analysis, endocrine parameters, ultrasound imaging, and fatherhood. Mean age at treatment commencement was 14.2 yr, and mean follow-up was 21.2 yr.

RESULTS

Sixty-six men (36 treated and 30 untreated) had attempted to achieve fatherhood. The probability of conceiving their first pregnancy within 1 yr was similar in treated and untreated men (26 vs. 24; Breslow P=0.8). Eleven treated and 13 untreated men presented with a left-sided varicocele (P=0.5). Testicular volume, sperm quality, and serum LH, FSH, and inhibin B levels were comparable between treated and untreated men. However, treated men had significantly reduced serum T levels, adjusted for known confounders [mean (sd) 13.3 (1.8) vs. 15.2 (1.9) nmol/liter; P=0.005). In addition, testicular volume and serum inhibin B and FSH levels in treated men were significantly correlated with age at treatment commencement.

CONCLUSION

At a mean follow-up of 21 yr after high-dose androgen treatment, we conclude that fatherhood and semen quality in tall treated men are not affected. Serum testosterone levels, however, are reduced in androgen-treated men. Future research is required to determine whether declining testosterone levels may become clinically relevant for these men as they age.

Development of an e-learning portal for pediatric endocrinology: educational considerations

BACKGROUND

Global accessibility and dissemination of developments in pediatric endocrinology prompted to examine how to develop an educational interactive e-SPE web portal.

METHODS

A systematic approach was used to identify the relevant aspects of accessibility and dissemination. An orientation at the big idea was made, executed by an analysis of the needs of student and teacher pediatric endocrinologists, a definition of the learning objectives, a research in educational literature and an exploration of ICT design specifications.

RESULTS

The intensive collaboration between medical, educational and information technology disciplines resulted in a portal design. The portal meets requirements of adult learning, stresses interaction between partners in learning and offers direct feedback during the learning process. The portal supports the development of not only knowledge but also competences both at junior and advanced levels.

CONCLUSION

When the e-SPE portal is completed, the options for summative assessment will be examined as a medium for international certification in conjunction with local and national requirements (http://espe.elearning.nl).

Stem cell factor as a novel diagnostic marker for early malignant germ cells

Carcinoma in situ (CIS) of the testis is the pre-invasive stage of type II testicular germ cell tumours (TGCTs) of adolescents and adults. These tumours are the most frequently diagnosed cancer in Caucasian adolescents and young adults. In dysgenetic gonads, the precursor of type II GCTs can be either CIS or a lesion known as gonadoblastoma (GB). CIS/GB originates from a primordial germ cell (PGC)/gonocyte, ie an embryonic cell. CIS can be cured by local low-dose irradiation, with limited side effects on hormonal function. Therefore, strategies for early diagnosis of CIS are essential. Various markers are informative to diagnose CIS in adult testis by immunohistochemistry, including c-KIT, PLAP, AP-2gamma, NANOG, and POU5F1 (OCT3/4). OCT3/4 is the most informative and consistent in presence and expression level, resulting in intense nuclear staining. In the case of maturational delay of germ cells, frequently present in gonads of individuals at risk for type II (T)GCTs, use of these markers can result in overdiagnosis of malignant germ cells. This demonstrates the need for a more specific diagnostic marker to distinguish malignant germ cells from germ cells showing maturation delay. Here we report the novel finding that immunohistochemical detection of stem cell factor (SCF), the c-KIT ligand, is informative in this context. This was demonstrated in over 400 cases of normal (fetal, neonatal, infantile, and adult) and pathological gonads, as well as TGCT-derived cell lines, specifically in cases of CIS and GB. Both membrane-bound and soluble SCF were expressed, suggestive of an autocrine loop. SCF immunohistochemistry can be a valuable diagnostic tool, in addition to OCT3/4, to screen for precursor lesions of TGCTs, especially in patients with germ cell maturation delay.

[Primary amenorrhea: constitutional delayed puberty or hormonal disturbance]

Investigations were carried out in 2 women of 17 and 18 years with primary amenorrhea, normal external female genitalia and delayed secondary sexual characteristics, for the reasons for delayed puberty. The 17-year-old patient had reduced values of FSH, LH and oestradiol. This disturbance in the hypothalamo-hypophysary axis was caused by hydrocephalus. Menarche occurred following drainage of the fluid. The 18-year-old patient had raised values ofFSH and LH and a lowered oestradiol value. There was therefore a disfunction existing at ovarian level, which appeared to be caused by an XX-gonadal dysgenesis. The patient was treated with hormones which led to breast development and menarche taking place. The cause ofprimary amenorrhea can mainly be divided into three categories: constitutional delayed puberty, delayed puberty due to hypogonadotropic hypogonadism, or delayed puberty due to hypergonadotropic hypogonadism. A carefully taken medical history, together with determination of the serum levels of FSH and LH, is helpful in differentiating between these categories. Subsequently, structured clinical management must be performed in order to approach the differential diagnosis of each of these categories, which will then be followed by the final diagnosis.

Final height after treatment of early puberty in short adopted girls with gonadotrophin releasing hormone agonist with or without growth hormone

OBJECTIVE

To compare final height data after treatment with gonadotrophin releasing hormone agonist (GnRHa) alone or in combination with growth hormone (GH) in short adopted girls with early puberty.

DESIGN

A randomized controlled trial.

PATIENTS AND METHODS

Twenty-six girls with onset of puberty before 10 years of age were treated for 3 years with either GnRHa alone (group A, n = 12) or with GnRHa and GH (group B, n = 14). Mean age at start of treatment was 9.6 years in both groups, bone age was 10.7 (SD 1.1) years in group A and 11.6 (0.8) years in group B.

RESULTS

Initial height prediction with average Bayley & Pinneau tables was 149.8 (5.6) and 146.8 (4.8) cm, respectively. Bone age at discontinuation of treatment was 12.3 (0.9) and 13.0 (0.6) years in group A and B, respectively. Height gain defined as the difference between initial height prediction and attained final height, was significantly different between group A and B (5.2 (3.7) and 8.2 (3.4) cm, P < 0.05) using average tables for height prediction. With accelerated tables for prediction the numbers were -1.0 (3.6) and 3.3 (3.5) cm, respectively. At final height, there was no significant difference in height: group A: 155.0 (5.6) cm and group B: 155.0 (5.5) cm.

CONCLUSIONS

After 3 years of GnRHa treatment in adopted girls with early puberty, FH is significantly higher than initial height prediction. The addition of GH resulted in a limited further increase in height gain. In the interpretation of the results methodological issues concerning height prediction have to be taken into account.

Early puberty in adopted children

Early puberty is frequently observed in adopted children. In various studies, early puberty has been associated with decreased final height. In Europe, studies were undertaken to treat early puberty in adopted children with GnRH agonist. This article reviews the current understanding of early puberty in adopted children, including prevalence, background and treatment options. Data from the European studies are briefly described. Besides auxological aspects, psychological items are addressed as well. Studies on the psychological effect of early puberty in adopted children are reported. Future issues include further study in the mechanism of early puberty in adopted children, evaluation of final height results of the growth studies and quality of life assessments in this specific group of children.

Early puberty in girls

Early puberty is not well defined in paediatric endocrinology. This chapter reviews the current insights on definitions, patient groups and treatment modalities in girls with early puberty. It is concluded that there is no clear evidence for a beneficial effect of gonadotrophin releasing hormone agonist (GnRHa) treatment in auxological terms. A clinical approach is presented, including both auxological and psychological items. Further research is needed to answer the question of whether early puberty should be treated with GnRHa.

Leydig cell hypoplasia: cases with new mutations, new polymorphisms and cases without mutations in the luteinizing hormone receptor gene

BACKGROUND

Defective male sex differentiation in patients with hypoplasia of Leydig cells (LCH) is caused by deficient LH receptor signal transduction. To further investigate the variety of LH receptor gene mutations present in LCH patients and their influence on the phenotype, we examined 10 nonrelated patients with the clinical presentation of LCH.

PATIENTS AND METHODS

Ten patients with a clinical phenotype of LCH were analysed for mutations in the complete coding region of the LH receptor gene. Exons 1-10 and two overlapping fragments of exon 11 of the LH receptor gene including all intron-exon boundaries were amplified by polymerase chain reaction and sequenced. To screen for frequencies of DNA changes, mutation analysis was performed on 45-59 healthy persons using denaturation high-performance liquid chromatography.

RESULTS

Six new DNA alterations were identified. Three of them appear to be new polymorphisms. A G to C change at the 28th nucleotide of intron 1 on one allele and a heterozygous CGA to CAA transition at codon 124 (R124Q) were found. Both findings in these two patients are polymorphisms that occur with a frequency of 17% and 1.7%, respectively. A silent heterozygous CTA to TTA change at codon 204 was identified. In a patient with micropenis, the analysis revealed a homozygous missense mutation at codon 625 (I625K). As reported previously, this alteration significantly impaired signal transduction and explains the partial phenotype. Finally, in one compound heterozygous patient, two different mutations were discovered. At the polymorphic site in exon 1, a 27-bp insertion (CTG)2 AAG (CTG)5 CAG and a premature stop codon in the transmembrane segment 4 (W491*) were found. Both mutations disrupt signal transduction and explain the complete phenotype of this patient. In five patients, no DNA alterations could be identified.

CONCLUSIONS

Three mutations (33 bp insertion in exon 1; W491* and I625K) were identified that explain the phenotype in two patients. In addition, most of the patients with the clinical phenotype of LCH did not have causative mutations, suggesting that changes in other regions of the LH receptor gene, such as the large introns or the promoter region, may be responsible for the majority of cases. Alternatively, the displayed phenotype may be the result of other genetic defects. Our work further underscores the importance of thorough clinical analysis of patients before molecular analysis of a particular gene is performed.