From mini-puberty to pre-puberty: early impairment of the hypothalamus-pituitary-gonadal axis with normal testicular function in children with non-mosaic Klinefelter syndrome.

PURPOSE: Klinefelter syndrome (KS) is a genetic disorder caused by the presence of an extra X chromosome in males. The aim of this study was to evaluate the hypothalamic-pituitary-gonadal (HPG) axis and the clinical profile of KS boys from mini-puberty to early childhood. PATIENTS AND METHODS: In this retrospective, cross-sectional, population study, 145 KS boys and 97 controls aged 0-11.9 years were recruited. Serum FSH, LH, testosterone (T), Inhibin B (INHB), sex hormone binding globulin (SHBG) and anti-Müllerian hormone (AMH) were determined. Auxological parameters were assessed. To better represent the hormonal and clinical changes that appear in childhood, the entire population was divided into 3 groups: ≤ 6 months (group 1; mini-puberty); > 6 months and ≤ 8 years (group 2; early childhood); > 8 and ≤ 12 years (group 3; mid childhood). RESULTS: During mini-puberty (group 1), FSH and LH were significantly higher in KS infants than controls (p < 0.05), as were INHB and T (respectively p < 0.0001 and p < 0.005). INHB was also significantly higher in KS than controls in group 2 (p < 0.05). AMH appeared higher in KS than in controls in all groups, but the difference was only statistically significant in group 2 (p < 0.05). No significant differences were found in height, weight, testicular volume, and penile length. CONCLUSIONS: No hormonal signs of tubular or interstitial damage were found in KS infants. The presence of higher levels of gonadotropins, INHB and testosterone during mini-puberty and pre-puberty may be interpreted as an alteration of the HPG axis in KS infants.

Adverse pathophysiological influence of early testosterone therapy on the testes of boys with higher grade sex chromosome aneuploidies (HGAs): a retrospective, cross-sectional study.

PURPOSE: Higher grade aneuploidies (HGAs) of the male sex chromosomes are a rare genetic group of pathologies caused by nondisjunction meiotic events. The aim of this study was to evaluate the impact of early androgenic therapy on the testicular secretory hormone profile, and the pathophysiological implications. PATIENTS AND METHODS: In this cross-sectional study, 18 HGA subjects aged 6-8 years were recruited. They were divided into two groups, based on whether or not they had previously undergone testosterone therapy (group 1: 11 untreated subjects; group 2: 7 treated subjects). Serum FSH, LH, testosterone (T), inhibin B (INHB) and anti-Müllerian hormone (AMH) were determined, and auxological parameters were assessed. Five group 1 patients and four group 2 patients were treated with hCG (human chorionic gonadotropin) for inguinal cryptorchidism; their hormone profile and auxological parameters were assessed both pre- and post-hCG treatment. RESULTS: Group 1 subjects showed significantly higher testicular volume and higher levels of AMH and INHB (p < 0.0001). Subjects who had undergone hCG therapy showed a significantly higher testicular volume, penis length (respectively, p = 0.008 and p = 0.0005 for group 1 and p = 0.04 and p = 0.001 for group 2) and T (p = 0.005 for group 1 and p = 0.004 for group 2). CONCLUSIONS: HGA patients undergoing early testosterone therapy show an earlier and persistent suppression of testicular secretory function. At this age, the testes are still responsive to stimulation with hCG. The selection of patients to be treated must be accompanied by a thorough clinical and hormonal evaluation.

Hormonal and metabolic gender differences in a cohort of myotonic dystrophy type 1 subjects: a retrospective, case-control study.

PURPOSE: Myotonic dystrophy type 1 (DM1) is a genetic disorder caused by CTG expansion in the DMPK gene. The aim was to investigate the endocrine and metabolic aspects of DM1. PATIENTS AND METHODS: Retrospective, case-control study. We compared pituitary, thyroid, adrenal, gonadal and liver function and glycolipid metabolism of 63 DM1 patients against 100 control subjects. Given age-related differences, 2 further subgroups were created to investigate the pituitary-gonadal axis: < 41 (1a) and ≥ 41 (1b) years old for male subjects and < 46 (2a) and ≥ 46 (2b) years old for female subjects. Testicular and thyroid ultrasounds were also performed in the DM1 group. RESULTS: FT3 and FT4 were significantly lower in DM1 men than controls, while for both males and females, thyroglobulin, ACTH and cortisol were significantly higher in the DM1 group. Gonadotropin levels were significantly higher and inhibin B and DHEA-S levels significantly lower in DM1 patients than controls for both male subgroups. Testosterone and SHBG were significantly higher in controls than in patients for subgroup 1a. Prolactin was significantly higher in patients in subgroups 1b, while testosterone was lower in subgroup 2a than in age-matched female controls. A correlation between the number of CTG repeats and the percentage of male hypogonadal subjects was found. Finally, there was a worse glucose and lipid pattern and significantly higher transaminase and gamma-GT levels in both male and female patients. CONCLUSIONS: The high frequency of endocrine and metabolic abnormalities in DM1 highlights the importance of endocrine monitoring to enable the prompt initiation of a suitable therapy.

Epicardial fat: the role of testosterone and lipid metabolism in a cohort of patients with Klinefelter syndrome.

CONTEXT: Klinefelter syndrome (KS), in which subjects have additional copies of X chromosomes, is the most common male sex chromosome abnormality, with a prevalence of 1 in 660 and an incidence of about 1 in 500-700 newborns. Its sign and symptoms include infertility, generally low testosterone levels, and an increased prevalence of obesity and metabolic syndrome. Epicardial fat thickness (EFT) reflects visceral adiposity rather than general obesity. OBJECTIVE: The aim of this study was to analyze echocardiographic EFT in a cohort of patients with KS in comparison with non-obese and obese euploid controls, and to evaluate its correlation with biochemical parameters. DESIGN, SETTING AND PARTICIPANTS: Two hundred and twenty-one KS patients referred to our Rare Endocrine Diseases clinic and 77 age-matched controls underwent Doppler echocardiography and a full investigation of anthropometric and body composition, Serum levels of total testosterone (T), estradiol (E2), sex hormone binding globulin (SHBG), fasting plasma glucose, insulin, cholesterol and triglycerides were obtained. All participants underwent dual energy X-ray absorptiometry (DEXA) scan to assess truncal body fat (TrBF). MAIN OUTCOME MEASURE: EFT, body composition and metabolic parameters in KS patients and how they are affected by genotype. RESULTS: EFT was greater in KS patients than in healthy non-obese (NOb) controls, but lower than in obese (OB) controls. When KS patients were divided into groups (hypogonadal; eugonadal; receiving testosterone replacement therapy [TRT]), EFT was greater in hypogonadal patients than in NOb controls and eugonadal patients, but showed no difference from the OB controls or TRT patients. Hypogonadal patients showed increased TrBF in comparison with NOb controls and eugonadal and TRT patients, and similar TrBF to OB controls. As expected, there was a strong correlation between BMI and EFT in both KS patients and controls (P < 0.0001). In contrast, there was a strong inverse correlation between testosterone and EFT in the control group, but not in KS patients. EFT was significantly correlated with TrBF in both populations (P < 0.0001). Multivariate analyses showed that the major determinants of both EFT and TrBF were BMI and the presence of KS itself. Testosterone and triglycerides were not included as variables in the models. CONCLUSION: EFT in hypogonadal KS subjects was similar to that of the obese eugonadal controls. Even though there was a direct correlation between BMI and EFT in both populations, the influence of TrBF on EFT was stronger. The presence of the supernumerary X chromosome appeared to be one of the strongest determinants of EFT and TrBF, independent of testosterone levels.

Incidence of Y chromosome microdeletions in patients with Klinefelter syndrome.

PURPOSE: The aim of this study was to study the incidence of Y chromosome microdeletions in a Caucasian population of Klinefelter syndrome (KS) patients and to investigate the possible association between Y chromosome microdeletions and KS. MATERIALS AND METHODS: We conducted a retrospective study on 118 KS patients, 429 patients with non-obstructive azoospermia (NOA), and 155 normozoospermic men. Eight of the 118 KS patients had undergone testicular sperm extraction (TESE). All patients underwent semen examination and Y chromosome microdeletions evaluated by PCR, using specific sequence tagged site (STS) primer sets, which spanned the azoospermia factor AZFa, AZFb, and AZFc regions of the Y chromosome. RESULTS: Semen analysis of the KS group revealed: 1 patient with oligozoospermia, 1 with severe oligoasthenoteratozoospermia, 2 with cryptozoospermia, and 114 with azoospermia. Eight of the 114 azoospermic KS patients underwent TESE, and spermatozoa were recovered from three of these, all of whom had non-mosaic karyotype 47, XXY. 10.7% of the NOA patients presented AZF microdeletions. In 429 cases with NOA, 8 cases had AZFa + b + c deletion, 6 cases had AZF b + c deletion, 4 cases had AZFa microdeletion, 8 cases had AZFb microdeletion, and 20 cases had AZFc microdeletion. Just one KS patient (0.8%) presented microdeletion in the AZFc region. CONCLUSION: The percentage of microdeletions in KS patients was lower than in NOA patients, suggesting that AZF microdeletions and KS do not have a causal relationship and that Y chromosome microdeletions are not a genetic factor linked to KS.

Long-term effect of testosterone replacement therapy on bone in hypogonadal men with Klinefelter Syndrome.

PURPOSE: To assess different aspects of bone damage in untreated adult patients with Klinefelter Syndrome (KS) before and during testosterone replacement therapy (TRT). METHODS: Fifteen untreated hypogonadal men with KS and 26 control subjects (C) matched for age and BMI were recruited. Sex hormone levels were measured in all subjects. Lumbar spine (LS) and femoral (neck: FN and total hip: TH) bone mineral density (BMD), trabecular bone score (TBS), hip structure analysis (HSA) and fat measures (percentage of fat mass, android/gynoid ratio and visceral adipose tissue) were evaluated by DEXA. In KS patients, blood analysis and DEXA measurements were assessed at baseline and repeated yearly for three years during TRT. RESULTS: Fat measures were significantly higher in KS than C (p < 0.01). In contrast, mean LS, FN and TH BMD were significantly reduced in KS compared to C (p < 0.01), while there was no difference in TBS. HSA revealed a significantly lower cortical thickness and significantly higher buckling ratio in KS compared to C at all femoral sites (p < 0.01). In KS patients, TRT significantly increased BMD at LS only, but did not improve TBS and HSA parameters. Fat measures were inversely associated with TBS values, and TRT did not influence this relationship. CONCLUSIONS: In untreated hypogonadal men with KS, lumbar and femoral BMD was reduced, and femoral bone quality was impaired. Adiposity seemed to have a detrimental effect on lumbar bone microarchitecture, as indirectly evaluated by TBS. However, TRT failed to remedy these negative effects on bone.

Fluid intelligence, traits of personality and personality disorders in a cohort of adult KS patients with the classic 47, XXY karyotype.

PURPOSE: Klinefelter's syndrome (KS) is associated with specific neurobehavioral features and personality traits. The aim of our study was to investigate fluid intelligence, personality traits and personality disorders (PD) and possible correlations with testosterone in a cohort of adult KS patients. METHODS: We analyzed 58 adult KS patients with the classic 47, XXY karyotype. The Structured Clinical Interview for axis II disorders was used to assess DSM IV personality disorders. Personality traits were assessed using MMPI-2. Fluid intelligence was tested by using Raven's Standard Progressive Matrices (SPM) Test. Testosterone blood concentration was measured by CMIA. RESULTS: PD prevalence was 31%. Four altered MMPI scales (Social Responsibility, Dominance, Ego Strength and Repression) were found in more than 40% of patients. Overcontrolled hostility and MacAndrew Alcoholism Scale-Revised scales were altered in the PD- group only. Biz-Odd Thinking and Post-Traumatic Stress Disorder scale were associated with the presence of personality disorder. The raw SPM score was 44 ± 10.8 without any significant correlation with testosterone. No significant difference in mean age, SPM raw score and MMPI score was observed between eugonadal, hypogonadal and treated patients. CONCLUSIONS: Most KS patients had average fluid intelligence. PD prevalence was higher than in the general population. Testosterone was not correlated with fluid intelligence, personality traits or PD, but a reduction in marital distress was observed in treated patients. This could suggest that testosterone therapy can improve physical symptoms and this effect could also improve relationship abilities and wellness awareness.

Klinefelter syndrome: cardiovascular abnormalities and metabolic disorders.

Klinefelter syndrome (KS) is one of the most common genetic causes of male infertility. This condition is associated with much comorbidity and with a lower life expectancy. The aim of this review is to explore more in depth cardiovascular and metabolic disorders associated to KS. KS patients have an increased risk of cerebrovascular disease (standardized mortality ratio, SMR, 2.2; 95% confidence interval, CI, 1.6-3.0), but it is not clear whether the cause of the death is of thrombotic or hemorrhagic nature. Cardiovascular congenital anomalies (SMR, 7.3; 95% CI, 2.4-17.1) and the development of thrombosis or leg ulcers (SMR, 7.9; 95% CI, 2.9-17.2) are also more frequent in these subjects. Moreover, cardiovascular abnormalities may be at least partially reversed by testosterone replacement therapy (TRT). KS patients have also an increased probability of endocrine and/or metabolic disease, especially obesity, metabolic syndrome and type 2 diabetes mellitus. The effects of TRT on these abnormalities are not entirely clear.

Reference ranges for thyroid hormones in normal Italian children and adolescents and overweight adolescents.

BACKGROUND: As thyroid hormones are essential for normal pubertal growth and sexual development, TSH, free T3 (FT3) and free T4 (FT4) levels undergo progressive modification during childhood and puberty. AIM: To establish thyroid hormone reference ranges in pre-pubertal children, pubertal adolescents, and adults and to evaluate any differences in thyroid function between overweight and normalweight pubertal subjects. SUBJECTS AND METHODS: Chemiluminescent microparticle immunoassay was used to analyze TSH, FT3 and FT4 concentrations in serum samples from 508 children and adolescents aged 6 to 18 yr and 100 healthy adults aged 30 to 60 yr, and from 68 overweight pubertal adolescents. As data were not normally distributed, we compared them through non-parametric tests for independent samples and the reference ranges were assumed to lie between the 2.5th and 97.5th percentile. RESULTS: We found a progressive and significant reduction in TSH, FT3, and FT4 levels in the three groups with increasing age. TSH levels were significantly higher in overweight patients than in the normal-weight group, but there were no significant differences for FT3 or FT4. CONCLUSIONS: This study revealed significant differences in levels of thyroid hormone between different age groups and allowed us to establish normal reference ranges for pre-pubertal children between 0.87-5.19 mIU/l for TSH, 4.75-8.59 pmol/l for FT3, and 13.09-20.61 pmol/l for FT4, and for pubertal adolescents between 0.76- 4.51 mIU/l for TSH, 4.26-8.46 pmol/l for FT3 and 10.94-19.09 pmol/l for FT4.

Multiple forms of hypogonadism of central, peripheral or combined origin in males with Prader-Willi syndrome.

BACKGROUND: Hypogonadism in Prader-Willi syndrome (PWS) is generally attributed to hypothalamic dysfunction or to primary gonadal defect, but pathophysiology is still unclear. OBJECTIVES: To investigate the aetiology of hypothalamic-pituitary-gonadal axis dysfunction in PWS males. METHODS: Clinical examination and blood sampling for luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, inhibin B and sexhormone-binding globulin (SHBG) were performed in 34 PWS patients, age 5·1-42·7 years, and in 125 healthy males of same age range. All participants were divided into two groups : < or ≥13·5 years. RESULTS: Pubertal PWS patients showed an arrest of pubertal development. Patients <13·5 years had normal LH, FSH, testosterone and 7/10 had low inhibin B. Among those ≥13·5 years, 8/24 patients had normal LH and testosterone, high FSH and low inhibin B. 5/24 had low FSH, LH, testosterone and inhibin B; one showed normal LH and FSH despite low testosterone and inhibin B; 4/24 had low testosterone and LH but normal FSH despite low inhibin B; 6/24 showed high FSH, low inhibin B and normal LH despite low testosterone. Compared with controls, patients <13·5 years had lower LH, inhibin B, similar FSH, testosterone, SHBG levels and testicular volume; those ≥13·5 years had smaller testicular volume, near-significantly lower LH, testosterone, SHBG, inhibin B and higher FSH. CONCLUSION: PWS patients display heterogeneity of hypogonadism: (i) hypogonadotropic hypogonadism of central origin for LH and/or FSH; (ii) early primary testicular dysfunction (Sertoli cells damage); and (iii) a combined hypogonadism (testicular origin for FSH-inhibin B axis and central origin for LH-T axis).

Strategies and advantages of early diagnosis in Klinefelter's syndrome.

Nearly 70 years after its description, Klinefelter's syndrome (KS) remains a largely undiagnosed condition. In addition to its typical characteristics of increased follicle-stimulating hormone secretion and small and firm testes, the syndrome presents an extremely wide spectrum of phenotypes. This could be explained by the possible presence of chromosomal mosaicism, androgen receptor polymorphisms and related heterogeneous endocrine abnormalities. The varied but relatively mild physical abnormalities also explain why many patients do not receive clinical attention until adulthood, when they seek medical advice on small testes or infertility. Diagnosis is also hindered by the low awareness of the disease among health professionals. This paper aims to review the possible signs of KS at different stages of life that could help achieve an early (or at least earlier) diagnosis. It has been demonstrated that the early diagnosis of KS improves patients' quality of life and enables better medical treatment. To achieve this, it is crucial to increase both medical and general awareness of the disease, including through use of the media and patients' associations.

Consensus statement on diagnosis and clinical management of Klinefelter syndrome.

Nearly 70 years after its description, Klinefelter syndrome (KS) remains a largely undiagnosed condition. As its clinical presentation may be subtle, many of those affected may be unaware or diagnosed only during evaluation for hypogonadism and/or infertility. In February 2010 an interdisciplinary panel of specialists met in Abano Terme (Padua, Italy) in a workshop on "Klinefelter Syndrome: diagnosis and clinical management". The main aim of this meeting was to discuss several aspects related to the epidemiology, pathogenesis, and evaluation of KS and to develop a consensus defining its early diagnosis and treatment. In the present consensus we have highlighted the features that may prompt the physicians to look after patients with KS both for the syndrome and correlated diseases. We have provided evidences that, during the different phases of life, there might be some advantages in establishing the diagnosis and starting proper follow-up and treatment. The workshop was carried out under the auspices of the Italian Society of andrology and Sexual Medicine (SIAMS).

Testicular function in boys previously treated with recombinant-human growth hormone for non-growth hormone-deficient short stature.

Data on the effects of recombinant human GH (hGH) therapy during male puberty on future testis function are still inconclusive. The aim of this study was to investigate the long-term effects of recombinant hGH treatment on reproductive function in non-GH-deficient short stature boys. Eight boys with non-GH-deficient short stature, affected by constitutional delay of puberty or idiopathic short stature, were retrospectively studied after recombinant-hGH treatment to verify gonadal development, hormone production and semen quality. Auxological data, endocrinological/ andrological parameters and laboratory evaluation (GH, IGF-I, FSH, LH, testosterone, inhibin B) were assessed before treatment; after completion of pubertal development, the same parameters plus SHBG levels were evaluated and a seminal fluid examination was conducted (ejaculate volume, pH, sperm concentration, total sperm count, forward and total motility, morphology). All patients showed normal testicular volume at the final pubertal stage, with regular androgenization. Hormonal levels were within the normal adult range in all boys. Considering the immature reproductive system of these patients in comparison with adults, semen parameters (sperm count, motility, and morphology) were within almost normal limits, except in one patient. Although patients showed the wide fluctuation of semen values frequently observed at the end of puberty, the hypophysis-gonadal axis hormones were in the normal range in all adolescents. Pathological measurements of some seminal parameters were found in one patient only. This study suggests that recombinant hGH treatment has no detrimental effects on the development and maturation of male gonadal function in non- GH deficient short stature young patients.

Changes in serum inhibin B during normal male puberty.

OBJECTIVE: In adult men, inhibin B (InhB) regulates FSH secretion by a negative feedback. The aims of this study were to evaluate the changes of InhB during puberty in the male and the relationship between InhB and FSH, LH, testosterone and testicular volume. DESIGN: Cross-sectional study. METHODS: InhB was measured using a two-site ELISA in 100 healthy boys subdivided by their pubertal development according to Tanner into five groups of 20. RESULTS: During puberty we observed an increase of InhB level (G1 = 84.3 pg/ml, G3 = 132.2 pg/ml, G5 = 206.1 pg/ml). In G1, InhB correlated positively with FSH (P = 0.0001), LH (P = 0.005), testosterone (P = 0.001) and testicular volume (P = 0.007); in G5, InhB correlated inversely with FSH (P = 0.001) and LH (P = 0.045) and directly with testicular volume (P = 0.013). The multivariate analysis demonstrated that: in G1, FSH is the most important, and testosterone the second most significant, stimulus for InhB increase; in G2 only FSH has a positive effect on InhB variation; in G3 only mean testicular volume fits the model (G1-G3: InhB dependent variable); considering the FSH dependent variable, in G4, InhB is the most important stimulus for FSH decrease and mean testicular volume is a secondary directly proportional variable; in G5, only InhB shows a significant inverse relationship with FSH. CONCLUSIONS: During puberty there is a regular increase of InhB. In the first phases of gonadal maturation, InhB and FSH correlate positively, while in mid-late stages the relationship is inverse. We found that in mid-puberty (G3-G4), the serum concentration of InhB increases, as its inverse relationship with FSH is being established and hence spermatogenesis.