Klinefelter syndrome in clinical practice

Mediastinal Tumor in a Boy With GnRH-Independent Precocious Puberty and Fluctuating β-HCG Levels

Gonadotropin-releasing hormone (GnRH(-independent premature puberty in boys, characterized by elevated β-human chorionic gonadotropin (β-hCG) levels, can indicate a secreting germ cell tumor (GCT). These tumors are rare but more common in individuals with Klinefelter syndrome (KS). We present a case of a 7.3-year-old boy with precocious puberty. Physical examination revealed bilateral testicular volumes of 8 to 10 mL and Tanner stage 3 secondary sexual characteristics (genitalia G3, pubic hair P3). His skeletal age was 12 years. Biochemical tests showed suppressed gonadotropin levels, elevated testosterone, and increased β-hCG of 86.6 mIU/mL (86.6 IU/L, reference range: <5 mIU/mL, <5 IU/L). Imaging, including magnetic resonance imaging (MRI), chest x-ray, whole-body computed tomography (CT), and testicular ultrasound, were interpreted as normal except for a small pineal cyst. Karyotype testing confirmed KS. Over 10 months, β-hCG levels fluctuated between 1 to 105 mIU/mL (1-105 IU/L). When β-hCG was 3.6 mIU/mL (3.6 IU/L), a fluorodeoxyglucose positron emission tomography-CT (FDG PET-CT) scan revealed a mediastinal tumor. The tumor was surgically removed and identified as a mature teratoma. This case underscores the importance of karyotype testing and repeated imaging in boys with premature puberty and elevated β-hCG levels, even if β-hCG levels decrease spontaneously and remain low.

Non-Obstructive Azoospermia and Intracytoplasmic Sperm Injection: Unveiling the Chances of Success and Possible Consequences for Offspring

Non-obstructive azoospermia (NOA) is found in up to 15% of infertile men. While several causes for NOA have been identified, the exact etiology remains unknown in many patients. Advances in assisted reproductive technology, including intracytoplasmic sperm injection (ICSI) and testicular sperm retrieval, have provided hope for these patients. This review summarizes the chances of success with ICSI for NOA patients and examines preoperative factors and laboratory techniques associated with positive outcomes. Furthermore, we reviewed possible consequences for offspring by the use of ICSI with testicular sperm retrieved from NOA patients and the interventions that could potentially mitigate risks. Testicular sperm retrieved from NOA patients may exhibit increased chromosomal abnormalities, and although lower fertilization and pregnancy rates are reported in NOA patients compared to other forms of infertility, the available evidence does not suggest a significant increase in miscarriage rate, congenital malformation, or developmental delay in their offspring compared to the offspring of patients with less severe forms of infertility or the offspring of fertile men. However, due to limited data, NOA patients should receive specialized reproductive care and personalized management. Counseling of NOA patients is essential before initiating any fertility enhancement treatment not only to mitigate health risks associated with NOA but also to enhance the chances of successful outcomes and minimize possible risks to the offspring.

Prenatal diagnosis of non-mosaic sex chromosome abnormalities: a 10-year experience from a tertiary referral center

OBJECTIVES

The aim of this study was to explore the frequency and profile of non-mosaic sex chromosome abnormalities detected in prenatal diagnosis over the past 10 years.

METHODS

We retrospectively reviewed pregnancies diagnosed with non-mosaic sex chromosome abnormalities between January 2012 and December 2021, using karyotyping and/or single nucleotide polymorphism (SNP) array. Maternal age, indications for testing, and outcomes were recorded.

RESULTS

Traditional karyotyping identified 269 (0.90 %) cases of non-mosaic sex chromosome abnormalities among 29,832 fetuses, including 249 cases of numerical abnormalities, 15 unbalanced structural abnormalities, and 5 balanced structural abnormalities. The overall detection rate of common sex chromosome aneuploidies (SCAs) was 0.81 %, with 47,XXY, 47,XXX, 47,XYY, and 45,X accounting for 0.32 , 0.19, 0.17, and 0.13 % respectively. All showed a fluctuating upward trend over the study period, except for 45,X. During the first five years (2012-2016), the major indication for testing was advanced maternal age (AMA), followed by abnormal ultrasound, abnormal noninvasive prenatal testing (NIPT), and abnormal maternal serum screening (MSS). In the second five years (2017-2021), the most frequent indication was abnormal NIPT, followed by AMA, abnormal ultrasound, and abnormal MSS. Among the 7,780 cases that underwent SNP array in parallel, an additional 29 clinically significant aberrations were detected. The most frequent aberration was a microdeletion in the Xp22.31 region, which was associated with X-linked ichthyosis.

CONCLUSIONS

Fetal sex chromosome abnormalities are important findings in prenatal diagnosis. The application of NIPT and SNP array technology has greatly improved the detection of SCAs and submicroscopic aberrations associated with sex chromosomes.

Male Infertility: Causes and Management at a Tertiary Care Center in India

Background Infertility and problems of impaired fecundity have been a concern through the ages and are also considerable clinical problems today, affecting many couples worldwide. Most infertility cases are primarily attributed to male factors, which play a significant role. Additionally, a substantial number of these patients exhibit suboptimal sperm parameters. The study is mainly designed for individual intervention and outcome. We aim to evaluate the demographics, etiology, utilization of treatments, and outcomes of males undergoing infertility treatment. Methodology We retrospectively enrolled infertile couples from January 2021 to March 2023, covering the past two years. All patients were evaluated and investigated per the study protocol to identify the cause of infertility. Results Two thousand three hundred forty-eight males were enrolled in the study, of whom 1,484 (63%) were found to have a standard semen analysis. A total of 868 (37%) had abnormal semen parameters. Two hundred and seventy-two (12%) patients completed the evaluation. All parameters, except for hypospermia, displayed lower percentages of motility compared to normozospermia. All semen parameters, except for hypospermia, showed a significantly lower normal morphology in comparison to normozospermia. This reduction increased by 10% for each year of age increment. Conclusions The study concluded by following a protocol for evaluating male patients. If an abnormal sperm parameter is identified before considering intracytoplasmic sperm injection (ICSI), it is recommended to conduct at least karyotyping and microdeletion analysis on the Y-chromosome's q arm.

The Klinefelter Syndrome and Testicular Sperm Retrieval Outcomes

Klinefelter syndrome (KS), caused by the presence of an extra X chromosome, is the most prevalent chromosomal sexual anomaly, with an estimated incidence of 1:500/1000 per male live birth (karyotype 47,XXY). High stature, tiny testicles, small penis, gynecomastia, feminine body proportions and hair, visceral obesity, and testicular failure are all symptoms of KS. Endocrine (osteoporosis, obesity, diabetes), musculoskeletal, cardiovascular, autoimmune disorders, cancer, neurocognitive disabilities, and infertility are also outcomes of KS. Causal theories are discussed in addition to hormonal characteristics and testicular histology. The retrieval of spermatozoa from the testicles for subsequent use in assisted reproduction treatments is discussed in the final sections. Despite testicular atrophy, reproductive treatments allow excellent results, with rates of 40–60% of spermatozoa recovery, 60% of clinical pregnancy, and 50% of newborns. This is followed by a review on the predictive factors for successful sperm retrieval. The risks of passing on the genetic defect to children are also discussed. Although the risk is low (0.63%) when compared to the general population (0.5–1%), patients should be informed about embryo selection through pre-implantation genetic testing (avoids clinical termination of pregnancy). Finally, readers are directed to a number of reviews where they can enhance their understanding of comprehensive diagnosis, clinical care, and fertility preservation.

Proportion of Chromosomal Disorders and Their Patterns among Births with Congenital Anomalies in Africa: A Systematic Review and Meta-Analyses

Introduction

Worldwide, surveys have shown that the frequency of chromosomal disorders among births with congenital anomalies varies greatly from country to country. It is well known that chromosomal disorders are an important cause of premature death or life-long disability; however, the absence of local epidemiological data on their birth prevalence and outcomes impedes policy and service development in many countries and continents. Therefore, the current systematic review and meta-analysis intend to show the pooled proportion of chromosomal disorders among births with congenital anomalies in Africa.

Methods

From PubMed, Cochrane Library, and Google Scholar, we systematically reviewed and meta-analyzed the studies that examined the incidence, prevalence, and types of chromosomal disorders using PRISMA guidelines. A weighted inverse variance random-effects model was used to estimate the pooled proportion of chromosomal disorders among births with congenital anomalies.

Results

From the total of 3,569 studies identified, 1,442 were from PubMed, 108 were from Cochrane Library, 1,830 were from Google Scholar, and 189 were from other sources. After duplication was removed, a total of 844 articles remained (2725 were removed by duplication). Finally, 144 full-text studies were reviewed and 60 articles with 52,569 births having congenital anomalies met the inclusion criteria and were selected for this meta-analysis. The pooled proportion of chromosomal disorders among births with congenital anomalies was 8.94% (95% CI; 7.02, 10.86; I ² = 98.8%; p < 0.001). Conclusions and Future Implications. In the current systematic review and meta-analysis, the pooled proportion of chromosomal disorders among births with congenital anomalies in Africa was small. Down syndrome (trisomy 21) accounted for more than 80% of chromosomal disorders. The pooled proportion of chromosome disorders was the highest in North African regions and countries compared to other regions of the continent. Healthcare managers should focus on establishing proper cytogenetic diagnostic facilities in collaboration with well-trained genetic counseling services in the continent.

Clinical features and prevalence of Klinefelter syndrome in transgender individuals: A systematic review

OBJECTIVE

Previous studies have suggested a higher prevalence of Klinefelter syndrome amongst transgender individuals. We undertook a systematic review to determine the prevalence of Klinefelter syndrome amongst transgender individuals presumed male at birth and summarize the clinical features and potential treatment implications for individuals with Klinefelter syndrome commencing gender-affirming hormone therapy.

DESIGN

Using preferred reporting items for systematic review and meta-analysis guidelines, we searched EMBASE, MEDLINE and the Cochrane Central Register of Controlled Trials (CENTRAL) up to 31 December 2021. All studies reporting on the prevalence or clinical features of transgender individuals with Klinefelter syndrome were included. This study is registered with the International Prospective Register of Systematic Reviews, number CRD42021227916.

RESULTS

Our search strategy retrieved 11 cohort studies comprising 1376 transgender individuals. In all, 14 of 1376 (1.02%) individuals were diagnosed with Klinefelter syndrome. Based on the seven studies in which karyotype was undertaken in all individuals, the prevalence is 9/1013 (0.88%; 95% CI, 0.41%-1.68%). Case reports highlight unique treatment considerations in this population, including azoospermia, venous thromboembolism, and monitoring of breast cancer and bone health.

CONCLUSIONS

Compared to the general population, observational studies document a higher prevalence of Klinefelter syndrome amongst transgender individuals, though underdiagnosis in the general population limits conclusions. Routine karyotype in transgender people initiating gender-affirming hormone therapy is not supported unless clinical features of Klinefelter syndrome, such as small testicular volume, or hypergonadotropic hypogonadism are present. Transgender individuals with Klinefelter syndrome need to manage a unique risk profile if they desire feminizing gender-affirming hormone therapy.

KIF2C affects sperm cell differentiation in patients with Klinefelter syndrome, as revealed by RNA-Seq and scRNA-Seq data

Klinefelter syndrome (KS) is a leading contributor to male infertility and is characterised by complex and diverse clinical features; however, genetic changes in the KS transcriptome remain largely unknown. We therefore used transcriptomic and single‐cell RNA sequencing (scRNA‐seq) datasets from KS versus normal populations through the Gene Expression Omnibus (GEO) database to identify gene biomarkers associated with the occurrence of KS. We identified a total of 700 differentially expressed genes (DEGs) and completed Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), enrichment pathway analysis and protein‐protein interaction (PPI) network analysis. A total of four unreported KS‐related hub genes (KIF2C, MRPS2, RPS15 and TSFM) were identified. Validation of the single‐cell sequencing dataset showed that only KIF2C and RPS15 were expressed in spermatocytes and that they were differentially expressed in sperm cells. Further construction of the developmental trajectories of these two genes in sperm cells showed that the KIF2C gene showed an upward trend throughout the differentiation and development of sperm cells. In conclusion, we report here that KIF2C may be closely related to the differentiation and development of sperm cells in KS patients, which is important for revealing the molecular mechanism of KS and conducting further studies.

Metabolic and Nutritional Aspects in Paediatric Patients with Klinefelter Syndrome: A Narrative Review

Klinefelter syndrome is the most common sex chromosomal aneuploidy in males. It is well known that patients with this syndrome have greater mortality and morbidity compared to the general population due to cardiovascular diseases and endocrine metabolism disorders. This augmented risk is due both to hypogonadism and to the syndrome itself. Therefore, correct hormonal replacement therapy and early primary prevention are crucial to these patients. Even though different studies are available on this topic in adult patients, only a few authors have focused on the paediatric population. Thus, in this narrative review, we report the current knowledge of metabolic and nutritional aspects in children with Klinefelter syndrome.

Congenital Aneuploidy in Klinefelter Syndrome with B-Cell Acute Lymphoblastic Leukemia Might Be Associated with Chromosomal Instability and Reduced Telomere Length

Simple Summary

Klinefelter syndrome (KS) is a rare congenital aneuploidy characterized by inherited gain of one X chromosome (XXY). KS is associated with higher susceptibility to the development of cancer. Somatic acquired chromosomal aberrations and chromosomal instability are hallmarks of cancer and leukemia but little is known about the cellular mechanisms involved. The conducted research aimed to identify genomic mechanisms involved in chromosomal evolution mechanisms important for leukemic development. In the leukemic blasts of a patient with KS and B-cell acute lymphoblastic leukemia (B-ALL), we identified additional acquired chromosomal aberration and a significant reduction in the length of the chromosomal ends, i.e., telomeres. A literature review of KS patients with B-ALL revealed that the majority of these patients had acquired two or more additional chromosomal aberrations at B-ALL diagnosis. These data indicate that enhanced reduction in telomere length might be associated with chromosomal instability and may serve as a future target for therapy or prevention.

Abstract

Rare congenital aneuploid conditions such as trisomy 13, trisomy 18, trisomy 21 and Klinefelter syndrome (KS, 47,XXY) are associated with higher susceptibility to developing cancer compared with euploid genomes. Aneuploidy frequently co-exists with chromosomal instability, which can be viewed as a “vicious cycle” where aneuploidy potentiates chromosomal instability, leading to further karyotype diversity, and in turn, paving the adaptive evolution of cancer. However, the relationship between congenital aneuploidy per se and tumor initiation and/or progression is not well understood. We used G-banding analysis, array comparative genomic hybridization analysis and quantitative fluorescence in situ hybridization for telomere length analysis to characterize the leukemic blasts of a three-year-old boy with KS and B-cell acute lymphoblastic leukemia (B-ALL), to gain insight into genomic evolution mechanisms in congenital aneuploidy and leukemic development. We found chromosomal instability and a significant reduction in telomere length in leukemic blasts when compared with the non-leukemic aneuploid cells. Reviewing published cases with KS and B-ALL revealed 20 additional cases with B-ALL diagnostic cytogenetics. Including our present case, 67.7% (14/21) had acquired two or more additional chromosomal aberrations at B-ALL diagnosis. The presented data indicate that congenital aneuploidy in B-ALL might be associated with chromosomal instability, which may be fueled by enhanced telomere attrition.

Crown heights in the permanent teeth of 47,XXY males and 47,XXX females

OBJECTIVE

Earlier results based on dental casts and radiographs have shown that additional X and Y chromosomes influence permanent and deciduous tooth crown sizes, with 47,XYY males exhibiting greater crown heights than 46,XY males. We studied here the effect of both X and Y chromosomes on tooth crown heights.

MATERIAL AND METHODS

The series consisted of 48 47,XXY males, 22 of their male relatives, and seven 47,XXX females with five female relatives. The population controls consisted of 27 males and 33 females. Measurements of all applicable teeth except for the third molars on both sides of the jaws were made on panoramic radiographs with a sliding digital calliper.

RESULTS

Apart from a few teeth, the mean crown heights in the 47,XXY males were greater than those in the male population controls, the differences being statistically significant for one tooth in the maxilla and ten teeth in the mandible. With the exception of two teeth, the 47,XXX females had taller tooth crowns than the female population controls, the differences in the two teeth being statistically significant. The 47,XXY males had greater tooth crown heights than the 47,XXX females, except in one tooth, and the differences were significant in two teeth. The tooth crown heights of the male relatives of the 47,XXY males and the female relatives of the 47,XXX females were close to those in the general population.

CONCLUSIONS

The present results demonstrated the effect of additional X and Y chromosomes in increasing crown heights. The differences between the 47,XXY males and 47,XXX females indicated a stronger effect of a Y chromosome on tooth crown height than of an X chromosome.

Syndromic male subfertility: a network view of genome-phenome associations

Background

Male infertility is a disorder of the reproductive system with a highly complex genetic landscape. In most cases, the reason for male infertility remains unknown; however, the importance of genetic abnormalities in the diagnosis of subfertility/infertility is becoming increasingly recognized. Several syndromes include impaired male fertility in the clinical picture, although a comprehensive analysis of genetic causes of the syndromology perspective of male reproduction is not yet available.

Objectives

(1) To develop a catalog of syndromes and corresponding genes associated with impaired male fertility and (2) to visualize an up‐to‐date genome–phenome network of syndromic male subfertility.

Materials and methods

Published literature was retrieved from the Online Mendelian Inheritance in Man, Orphanet, Human Phenotype Ontology and PubMed databases using keywords “male infertility,” “syndrome,” “gene,” and “case report”; time period from 1980 to September, 2021. Retrieved data were organized as a catalog and complemented with identification numbers of syndromes (MIM ID) and genes (Gene ID). The genome–phenome network and the phenome network were visualized using Cytoscape and Gephi software platforms. Protein–protein interaction analysis was performed using STRING tool.

Results

Retrieved syndromes were presented as (1) a catalog containing 63 syndromes and 93 associated genes, (2) a genome–phenome network including CHD7 and WT1 genes and Noonan and Kartagener syndromes, and (3) a phenome network including 63 syndromes, and 25 categories of clinical features.

Discussion

The developed catalog will contribute to the advances and translational impact toward understanding the factors of syndromic male infertility. Visualized networks provide simple, flexible tools for clinicians and researchers to quickly generate hypotheses and gain a deeper understanding of underlying mechanisms affecting male reproduction.

Conclusion

Recognition of the significance of genome–phenome visualization as part of network medicine can help expedite efforts toward unravelling molecular mechanisms and enable advances personal/precision medicine of male reproduction and other complex traits.

Klinefelter syndrome presenting with perinatal ascites associated with unilateral renal agenesis and a prostatic utricle cyst

We present a rare case of Klinefelter syndrome who presented with perinatal ascites, unilateral renal agenesis and a prostatic utricle cyst. The patient was born at term via emergency Caesarean section with gross abdominal distension. Antenatally, amniocentesis revealed a fetal karyotype of Klinefelter syndrome (47, XXY), and the 34-week ultrasound scan showed a cyst measuring 17×21×27 mm located inferior-posterior to the bladder. There was no ascites noted then, but a small left pelvic kidney was present. Ultrasound kidney, ureter and bladder as well as CT scan of the thorax, abdomen and pelvis done at birth showed a solitary right kidney with large-volume ascites and no evidence of a cyst adjacent to the bladder. These findings suggest urinary ascites from an involuting left renal system or a ruptured prostatic utricle cyst. We report the first case of Klinefelter syndrome associated with a prostatic utricle cyst and unilateral renal agenesis, presenting with neonatal ascites.

Clinical and laboratory differences between chromosomal and undefined causes of non-obstructive azoospermia: A retrospective study

BACKGROUND

Knowledge of clinical and laboratory differences between chromosomal and undefined causes aids etiological research on non-obstructive azoospermia.

OBJECTIVE

Compare clinical and laboratory differences between men with non-obstructive azoospermia due to chromosomal anomalies versus undefined causes.

DESIGN AND SETTING

A cross-sectional retrospective study conducted at a public university hospital in Campinas (Brazil).

METHODS

All men aged 20-40 years with non-obstructive azoospermia were included in the analysis.

RESULTS

The 107 cases included 14 with Klinefelter syndrome (KS) (13%), 1 with mosaic KS, 4 with sex development disorders (2 testicular XX, 1 NR5A1 gene mutation, and 1 mild androgen insensitivity syndrome) (4%), 9 with other non-obstructive azoospermia etiologies (8%), and 79 with undefined causes. The 22 chromosomal anomaly cases (14 KS, 1 mosaic KS, 2 testicular XX, 4 sex chromosome anomalies, and 1 autosomal anomaly) were compared with the 79 undefined cause cases. The KS group had lower average testicular volume, shorter penile length, and lower total testosterone levels but greater height, arm span, serum luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels, and gynecomastia frequency (absent in the undefined group and affecting more than half of the KS group). Patients with testicular XX DSD had LH, FSH, and penile length data intermediate between the KS and undefined cause groups, testicular volume similar to the KS group, and other data similar to the undefined group.

CONCLUSION

Clinical and laboratory data differentiate men with non-obstructive azoospermia and chromosomal anomalies, particularly KS and testicular XX, from those with undefined causes or other chromosomal anomalies.

Karyotypic abnormalities and Y chromosome microdeletions: How do these impact in vitro fertilization outcomes, and how common are they in the modern in vitro fertilization practice?

Objective

To examine the outcomes of in vitro fertilization with intracytoplasmic sperm injection (IVF-ICSI) in couples in whom the male partner has a karyotypic abnormality or Y chromosome microdeletion (YCM).

Design

Retrospective cohort.

Setting

Single infertility center.

Patient(s)

Couples treated with IVF-ICSI from January 2014 to April 2019 with male factor infertility, sperm concentration of <5 × 10⁶ sperm/mL, and results for karyotype and/or YCM panel.

Intervention(s)

In vitro fertilization with intracytoplasmic sperm injection.

Main Outcome Measure(s)

In couples in whom the male partner had a karyotypic abnormality or YCM: live birth rate/ongoing pregnancy rate, lack of partner sperm for fertilization, complete fertilization failure, cycle cancellation, and no embryos for transfer. The prevalence of karyotypic abnormalities and YCMs in the IVF population was calculated.

Result(s)

The live birth rate/ongoing pregnancy rate for those using partner sperm was 51.4% per transfer. However, 8.5% of cycles that intended to use partner sperm and 22.2% of cycles that intended to use surgically extracted partner sperm had no sperm available. Of cycles that created embryos with partner sperm, 12.5% had no embryo to transfer. The prevalence of karyotypic abnormalities was similar to previous reports (6.0%), while that of YCMs was lower (4.4%). Azoospermia factor a and b mutations were not represented in this population.

Conclusion(s)

It is reasonable to attempt IVF-ICSI with partner sperm in patients with genetic causes of male infertility. Patients should be counseled regarding the possibility of no sperm being available from the male partner, poor/failed fertilization, and genetic implications for potential offspring. Contingency plans, including IVF with donor sperm backup or oocyte cryopreservation, need to be made for these scenarios.

A rare variant Klinefelter syndrome seen 40 years later: 47,X,del(Xq24),Y

Patients with Klinefelter syndrome (KS) show a typically 47,XXY karyotype; however, some variations have been observed, including 47,XX,der(Y), 46,XY/47,XXY, 48,XXXY, 48,XXYY, and mosaicism or structural sex chromosome abnormalities in some patients. In the literature, a rare KS variant, 47,X,del(Xq),Y karyotype, was reported in only a few cases prior to 1981. A 40-year-old man (IV-3) was referred to our department due to infertility. His phenotype did not differ from the classic KS phenotype. He had two siblings (1-male; 1-female). His brother (IV-5) had mental retardation and died one year earlier at age 32. Additionally, his sister (IV-2) also had a history of infertility due to her husband's azoospermia. His mother had a history of 12 miscarriages. Karyotype analysis revealed the 47,X,del(Xq24),Y karyotype, and no deletions were seen in the AZF and SRY regions. We thought this chromosomal abnormality in the patient might have resulted from X-autosome translocation in one of his parents since his mother had recurrent pregnancy loss and his sibling had mental retardation. However, we could not confirm it due to his parents were not alive. This study shows the first case of a long-arm X-chromosome deletion after a long period and reviews current knowledge concerning variant KS (deletion Xq).

Identification of genomic imbalances (CNVs as well as LOH) in sertoli cell only syndrome cases through cytoscan microarray

Sertoli cell only syndrome (SCOS) is characterized by complete absence of germ cells in seminiferous tubules of testis. SCOS is multifactorial but genetic factors play a major role in pathogenesis of the disorder with idiopathic origin. Genetic factors majorly include sex chromosomal aneuploidy and Yq Microdeletion. But a large number of cases are still idiopathic. The study aimed to evaluate the genomic imbalances (CNVs and LOH) in idiopathic SCOS patients. The study is based on 28 apparent idiopathic SCOS cases and 10 controls. Molecular cytogenetic techniques viz., FISH, STS-Multiplex PCR and Affymetrix cytoscan microarray (750 K) were used. The microarray screened whole genomic imbalances in DNA from peripheral blood of 25 cases (excluded Klinefelter syndrome patients) and testicular FNAC sample of 2 cases. High FSH and low Inhibin B were observed in cases as compared to control controls groups. Four cases of sex chromosomal abnormality (i.e., three non-mosaic 47, XXY males and one non-mosaic 46, XX male) as well as four cases of Yq microdeletion (i.e., three cases with AZFc deletion and one case with complete AZFa, b and c deletion) were identified. Microarray detected unbalanced translocation of two segments of Y-chromosome i.e., Yp11.31-p11.2 (~4.o mb region, involving SRY) and Yp11.2 (~2.5 mb region) on X-chromosome in XX male. Also, loss of segment on same X-chromosome involving PAR1 region was identified. We have identified both autosomal and sex chromosomal CNVs (recurrent as well as private) involving candidate genes like SYCE1, ZFPM2, SRPK1, DAZ1, BPY2, HSFY1, VCY1 etc. All these CNVs are possibly associated with SCOS pathogenesis. CNVs identified in cases were already reported as pathogenic variant in clinical database DECIPHER. Microarray also detected many LOH (all autosomal, >3.0 mb size) that covered genes with spermatogenesis related function. The mechanism of action of LOH in pathogenesis of SCOS still remains unravelled. CNVs and LOH related to spermatogenesis identified from two different sample types (blood vs. testicular tissue) were discordant. This study should be extended for larger cohort of patients.

Klinefelter syndrome in an adolescent with severe obesity, insulin resistance, and hyperlipidemia, successfully treated with testosterone replacement therapy

Klinefelter syndrome (KS) is a sex chromosome disorder characterized by the presence of one or more extra X chromosomes. KS is well known by the common karyotype 47, XXY and presents as male infertility with hypogonadism in adults. Pediatric patients with KS commonly show neurodevelopmental disorders and cryptorchidism. We have reported a case of a 14-yr-old boy with KS and severe obesity (body mass index, 38.1 kg/m²), insulin (IRI) resistance (homeostatic model assessment 1 IRI resistance, 9.26), hyperlipidemia (serum low-density lipoprotein cholesterol level, 192 mg/dL; serum triglyceride level, 239 mg/dL), hypergonadotropic hypogonadism, and learning difficulties. The karyotype was 47, XXY, t(4;5) (q21.2;q32). Initially, he was unwilling to accept dietary restrictions and perform physical exercise against obesity. Testosterone replacement therapy was initiated at 16 years of age, which successfully improved the body composition, IRI resistance, and hyperlipidemia and increased the serum testosterone levels. Additionally, he adhered to recommendations for exercise and dietary restrictions. Patients with KS have risks of obesity and metabolic syndrome with sarcopenic conditions due to hypergonadotropic hypogonadism. Pediatricians should be aware of KS as a primary disease causing obesity. Testosterone replacement therapy could help ameliorate obesity and its comorbidities in patients with obesity and KS.

Androgen Treatment in Adolescent Males With Hypogonadism

During adolescence, androgens are responsible for the development of secondary sexual characteristics, pubertal growth, and the anabolic effects on bone and muscle mass. Testosterone is the most abundant testicular androgen, but some effects are mediated by its conversion to the more potent androgen dihydrotestosterone (DHT) or to estradiol. Androgen deficiency, requiring replacement therapy, may occur due to a primary testicular failure or secondary to a hypothalamic–pituitary disorder. A very frequent condition characterized by a late activation of the gonadal axis that may also need androgen treatment is constitutional delay of puberty. Of the several testosterone or DHT formulations commercially available, very few are employed, and none is marketed for its use in adolescents. The most frequently used androgen therapy is based on the intramuscular administration of testosterone enanthate or cypionate every 3 to 4 weeks, with initially low doses. These are progressively increased during several months or years, in order to mimic the physiology of puberty, until adult doses are attained. Scarce experience exists with oral or transdermal formulations. Preparations containing DHT, which are not widely available, are preferred in specific conditions. Oxandrolone, a non-aromatizable drug with higher anabolic than androgenic effects, has been used in adolescents with preserved testosterone production, like Klinefelter syndrome, with positive effects on cardiometabolic health and visual, motor, and psychosocial functions. The usual protocols applied for androgen therapy in boys and adolescents are discussed.

Androgenization in Klinefelter syndrome: Clinical spectrum from infancy through young adulthood

Klinefelter syndrome (KS) is an uncommon chromosomal disorder in males that has a variable clinical appearance. Classic KS involves an extra X chromosome, (47, XXY), although other variations may exist, including a milder mosaic form as well as multiple extra sex chromosomes with more dramatic phenotypes. KS is underdiagnosed, especially pre-pubertally, owing to a paucity of concrete clinical signs; however, diagnostic rates increase during and after puberty, as the consequences of hypergonadotropic hypogonadism begin to manifest. Testicular failure causing decreased circulating testosterone (T) and germ cell depletion, a hallmark feature in KS, commonly begins shortly after the onset of puberty and leads to the most commonly recognized KS traits: small testes, azoospermia, gynecomastia, decreased facial and pubic hair. While many KS men maintain adequate T levels leading up to young adulthood, some may have lower T levels at an earlier age leading to varied levels of androgenization and clinical KS features. At certain critical time points, absent or decreased T may alter the development of normal male reproductive organs, external genitalia, development of secondary sexual characteristics and spermatogenesis. Testicular failure in utero may lead to ambiguous genitalia, cryptorchidism and/or hypospadias, all of which depend on fetal T production. In the neonatal period and childhood, decreased T levels during the mini-puberty of infancy may negatively impact germ cell differentiation and male neuropsychological development. Finally, decreased T during pubertal and young adulthood can lead to decreased virilization during puberty, eunuchoid skeleton and decreased spermatogenesis. Depending on the timing of the testicular failure, a reproductive window of sperm production may exist to achieve paternity for KS men. The presence or absence of clinical characteristics reflecting decreased androgenization provides an insight to the relative testicular function during these developmental time points for those with KS and contributes to variability within the syndrome.

Lessons learnt from the variation across 6741 family/general practices in England in the use of treatments for hypogonadism

INTRODUCTION

We have previously reported rates of diagnosis of male hypogonadism in United Kingdom (UK) general practices. We aimed to identify factors associated with testosterone prescribing in UK general practice.

METHODS

We determined for 6741 general practices in England, the level of testosterone prescribing in men and the relation between volume of testosterone prescribing and (1) demographic characteristics of the practice, (2) % patients with specific comorbidities and (3) national GP patient survey results.

RESULTS

The largest volume (by prescribing volume) agents were injectable preparations at a total cost in the 12-month period 2018/19 of £8,172,519 with gel preparations in second place: total cost £4,795,057. Transdermal patches, once the only alternative to testosterone injections or implants, were little prescribed: total cost £222,022. The analysis accounted for 0.27 of the variance in testosterone prescribing between general practices. Thus, most of this variance was not accounted for by the analysis. There was a strong univariant relation (r = .95, P < .001) between PDE5-I prescribing and testosterone prescribing. Other multivariant factors independently linked with more testosterone prescribing were as follows: HIGHER proportion of men with type 2 diabetes(T2DM) on target control (HbA1c ≤ 58 mmol/mol) and HIGHER overall practice rating on the National Patient Survey for good experience, while non-white ethnicity and socio-economic deprivation were associated with less testosterone prescribing. There were a number of comorbidity factors associated with less prescribing of testosterone (such as T2DM, hypertension and stroke/TIA).

CONCLUSION

Our analysis has indicated that variation between general practices in testosterone prescribing in a well developed health economy is only related to small degree (r²  = 0.27) to factors that we can define. This suggests that variation in amount of testosterone prescribed is largely related to general practitioner choice/other factors not studied and may be amenable to measures to increase knowledge/awareness of male hypogonadism, with implications for men's health.

The Expert in the Room: Parental Advocacy for Children with Sex Chromosome Aneuploidies

OBJECTIVE

Owing to fragmentation in the medical system, many parents of children with disabilities report taking on a care coordinator and advocate role. The parental advocacy and care coordination requirements are further amplified in this population because of a lack of awareness about sex chromosome aneuploidies (SCAs) in medical and social services settings, as well as the complex needs of affected children. This burden disproportionately affects mothers and low-resource families as a result of gendered ideas of parenthood and social stratification in resource access. The aim of this study is to understand the unique parental burdens of SCAs and family support needs.

METHODS

We conducted 43 interviews with individuals with SCAs and/or their parents and qualitatively coded and analyzed the transcripts for themes relating to parent advocacy, medical services, social and educational services, and coping.

RESULTS

Our findings indicate that parents must repeatedly advocate for their concerns about their child to be taken seriously before diagnosis and continue to advocate for services and interventions throughout childhood and adolescence. Parents also report the need to educate health care professionals about their child's medical condition. A majority of the parent participants were women, and single mothers reported high levels of emotional burden.

CONCLUSION

Parents of children with SCAs shoulder additional roles of medical advocate and care coordinator. This causes excessive burden on families but also disadvantages families in which parents are unable to act as an advocate for their child.

Genetics of Azoospermia

Azoospermia affects 1% of men, and it can be due to: (i) hypothalamic-pituitary dysfunction, (ii) primary quantitative spermatogenic disturbances, (iii) urogenital duct obstruction. Known genetic factors contribute to all these categories, and genetic testing is part of the routine diagnostic workup of azoospermic men. The diagnostic yield of genetic tests in azoospermia is different in the different etiological categories, with the highest in Congenital Bilateral Absence of Vas Deferens (90%) and the lowest in Non-Obstructive Azoospermia (NOA) due to primary testicular failure (~30%). Whole-Exome Sequencing allowed the discovery of an increasing number of monogenic defects of NOA with a current list of 38 candidate genes. These genes are of potential clinical relevance for future gene panel-based screening. We classified these genes according to the associated-testicular histology underlying the NOA phenotype. The validation and the discovery of novel NOA genes will radically improve patient management. Interestingly, approximately 37% of candidate genes are shared in human male and female gonadal failure, implying that genetic counselling should be extended also to female family members of NOA patients.

Prenatal Genetic Diagnosis of a Sex Chromosome Aneuploidy: Parent Experiences

Sex chromosome aneuploidies (SCAs) occur in 1 in every 400 births. SCAs are highly variable and have uncertain prognoses, complicating the delivery of prenatal cell-free DNA (cfDNA) results or diagnosis following amniocentesis or chorionic villus sampling. Using a mixed-methods approach, we explored the experiences of parents receiving a prenatal diagnosis of a fetus with SCA. Responses to open-ended questions were qualitatively analyzed. Of the 323 parents who completed the survey, 122 received a prenatal diagnosis and answered at least one open-ended question. Most parents did not recall being informed that cfDNA screening or amniocentesis could reveal the presence of a SCA prior to testing and described feeling unprepared for a positive result. Variation was found between parents who were delivered a diagnosis by a genetic professional versus other clinical specialties. Many parents expressed that the diagnosis was delivered in a way that emphasized the negative attributes of the SCA and that they were provided limited support materials. Parents who received a prenatal diagnosis of a SCA expressed a desire for more supportive delivery of prenatal diagnosis that focuses on parental education and nuanced discussion of potential phenotypes. Genetic counselors should be aware of the range of parental experiences when receiving a SCA diagnosis from non-genetic providers. Prenatal SCA diagnoses are predicted to increase as prenatal cfDNA screening becomes more widely used. Collaborations for greater provider education and comprehensive materials on SCAs are essential to facilitate the delivery of SCA diagnoses and improve parent understanding and support.

Testosterone target therapy: focus on immune response, controversies and clinical implications in patients with COVID-19 infection

The pandemic acute respiratory syndrome coronavirus 2 (SARS-CoV-2) named COVID-19 is causing a severe health emergency, and an individual's hormonal milieu may play an important role in both susceptibility to infection and severity of clinical course. We analyzed the role of testosterone in the immune response, and we hypothesized possible mechanisms to explain the high incidence of COVID-19 infection and a worse clinical course in elderly male patients. Testosterone may impair the immune response, and this effect could explain the greater susceptibility of men to infection. Transmembrane serine protease 2 (TMPRSS2) plays a crucial role in the entry of the virus into the respiratory epithelial cells, leading to COVID-19 disease. It is crucial to emphasize that testosterone levels and chemical castration (e.g. by androgen deprivation therapy for prostate cancer) may have contrasting roles in the phases of COVID-19 infection. Whereas low testosterone levels may be protective against the initial susceptibility (due to a restoration of immunological functions and a block of TMPRSS2), low testosterone may stimulate a worse clinical course in the advanced COVID-19 infection as it could exacerbate or activate the cytokine storm. If testosterone levels play these different roles, it is necessary to carefully identify patients for any indicated testosterone manipulation.

Klinefelter syndrome or testicular dysgenesis: Genetics, endocrinology, and neuropsychology

Klinefelter syndrome (47,XXY) is a frequent chromosomal disorder among males, often presenting with hypergonadotropic hypogonadism, small firm testicles, metabolic disorders, neurocognitive challenges, and increased height. Neurologic disorders such as epilepsy, seizures, and tremor as well as psychiatric disorders are also seen more frequently. The neurocognitive deficits seen are present in many areas of cognition, typically affecting general cognitive abilities, language, and executive functioning. Also, social dysfunction is frequent. Dyslexia is present in more than half of all males. Brain imaging studies generally show a typical pattern, with many nuclei and brain areas being smaller than among controls. However, it has not been possible to link the brain alterations found in imaging studies with the neurocognitive profile. The genetics underlying the phenotypic traits found among males with Klinefelter syndrome still remains to be elucidated; however, recent studies have described pervasive changes in the methylome and transcriptome and new and interesting candidate genes have been pinpointed, but their involvement in the phenotype of Klinefelter syndrome has not been proven.

Delayed and Precocious Puberty: Genetic Underpinnings and Treatments

Delayed puberty may signify a common variation of normal development, or indicate the presence of a pathologic process. Constitutional delay of growth and puberty is a strongly familial type of developmental pattern and accounts for the vast majority of children who are "late bloomers." Individuals with sex chromosomal abnormalities frequently have hypergonadotropic hypogonadism. There are currently 4 known monogenic causes of central precocious puberty. The primary treatment goal in children with hypogonadism is to mimic normal pubertal progression, while the primary aims for the management of precocious puberty are preservation of height potential and prevention of further pubertal development.

Infertility considerations in klinefelter syndrome: From origin to management

Klinefelter syndrome (KS) is defined as the presence of one or more extra "X" chromosome in a male patient. It affects approximately 1 in 600 newborn males and the most common chromosomal abnormality, leading to male hypogonadism and infertility. There is a lack of data supporting best practices for KS patients' care. In this paper we review controversial issues in KS research ranging from mechanisms of variation in KS phenotype to abnormalities resulting in reduced sperm production to successful sperm retrieval disparities after testicular sperm extraction (TESE). Translation to live birth and offspring health is also examined. Finally, medical therapies used to optimize the hormonal status and chances of fertility in KS patients are reviewed. We will also discuss the experimental spermatogonial stem cell (SSC) treatments, which are considered the future for TESE negative patients.

Establishment of an iPSC cohort from three unrelated 47-XXY Klinefelter Syndrome patients (KAUSTi007-A, KAUSTi007-B, KAUSTi009-A, KAUSTi009-B, KAUSTi010-A, KAUSTi010-B)

Klinefelter Syndrome (KS) is caused by the presence of a supernumerary X chromosome. Cytogenetic studies revaled that 80-90% of patients carry a 47-XXY karyotype, while 10-20% of cases are represented by mosaic 46-XY/47-XXY and high-grade aneuploidies 48-XXXY and 48-XXYY. The phenotypic traits of KS are highly variable across individuals and include cognitive dysfunction, metabolic dysregulation, osteoporosis, and cardiovascular diseases. Here, we describe the derivation of multiple 47-XXY iPSC lines from three unrelated KS patients to study the impact of supernumerary X chromosome during early development.

Chromosomal abnormalities and atrial fibrillation and ischemic stroke incidence: a nationwide population-based study

There is a paucity of information as to whether chromosomal abnormalities, including Down Syndrome, Turner Syndrome, and Klinefelter Syndrome, have an association with atrial fibrillation (AF) and ischemic stroke development. Data from 3660 patients with Down Syndrome, 2408 with Turner Syndrome, and 851 with Klinefelter Syndrome without a history of AF and ischemic stroke were collected from the Korean National Health Insurance Service (2007–2014). These patients were followed-up for new-onset AF and ischemic stroke. Age- and sex-matched control subjects (at a ratio of 1:10) were selected and compared with the patients with chromosomal abnormalities. Down Syndrome patients showed a higher incidence of AF and ischemic stroke than controls. Turner Syndrome and Klinefelter Syndrome patients showed a higher incidence of AF than did the control group, but not of stroke. Multivariate Cox regression analysis revealed that three chromosomal abnormalities were independent risk factors for AF, and Down Syndrome was independently associated with the risk of stroke. In conclusion, Down Syndrome, Turner Syndrome, and Klinefelter Syndrome showed an increased risk of AF. Down Syndrome patients only showed an increased risk of stroke. Therefore, AF surveillance and active stroke prevention would be beneficial in patients with these chromosomal abnormalities.

Clinical manifestation, diagnosis, and treatment of Klinefelter syndrome

Klinefelter syndrome is the most common congenital chromosomal syndrome in men. Clinical manifestations of Klinefelter syndrome vary greatly depending on the level of expression of the added X chromosome, the sensitivity of the androgen receptor, and the testosterone level. On average, the likelihood of a lifetime diagnosis of Klinefelter syndrome patients is less than 40%, and more than 60% of patients are unaware of their condition. Klinefelter syndrome patients in infancy sometimes have speech impairment; however, there are more cases without symptoms. In the early stages of puberty, there are many normal puberty development cases, but after mid-puberty, secondary sexual characteristics stop progressing. In adulthood, it is often diagnosed as a non-obstructive azoospermia disease. After middle-age, an increase in various metabolic disorders due to testosterone reduction appears as the main symptom. Testosterone treatment can promote the development of secondary sexual characteristics from puberty. Diagnosing a patient with Klinefelter syndrome due to infertility in adulthood may cause a psychological shock; therefore, a psychotherapeutic approach is also essential. Klinefelter syndrome is a disease that requires lifelong management, and in most cases the quality of life of patients and their families can be improved with appropriate therapeutic intervention. Because there are many cases without symptoms, it is important to screen suspected patients through active chromosomal testing.

Disorders of Pubertal Onset

Evaluation of the child with abnormal pubertal development can be challenging for the primary care provider. Understanding the factors associated with timing of pubertal onset and the normal sequence of pubertal changes is useful in evaluation of children with puberty disorders. A thorough workup includes assessment of growth rate, Tanner staging, and rate of pubertal progression, in addition to an extensive history and physical examination to identify signs and symptoms of disorders associated with abnormal pubertal timing. Initial diagnostic studies will most often include a bone age, levels of gonadotropins, and levels of estradiol (for girls) or testosterone (for boys).

Family experiences and attitudes about receiving the diagnosis of sex chromosome aneuploidy in a child

The most common sex chromosome aneuploidies (SCA) (47, XXY; 47, XYY; 47, XXX) frequently result in a milder phenotype than autosomal aneuploidies. Nevertheless, these conditions are highly variable and more symptomatic phenotypes may require significant clinical involvement, including specialty care. While historically most individuals with mild phenotypes remained undiagnosed during their lifetime, the increasing use of genetic testing in clinical care has increased the prenatal and postnatal diagnosis of SCAs. These genetic tests are frequently ordered by nongenetic providers who are also responsible for delivering the diagnosis. We surveyed parents of children (n = 308) to evaluate their experience of receiving a diagnosis and their support needs. The majority (73.3%) received the diagnosis from a nongenetic medical provider. Following a prenatal diagnosis parents reported experiencing depression, anxiety, and less optimism than those receiving a postnatal diagnosis. Few parents reported receiving materials explaining their child's condition that they found to be up-to-date, accurate, and unbiased. The frequently negative reported experiences of parents at time of diagnosis suggests more educational opportunities should be provided for nongenetic providers in order to become more informed about these conditions and communicate the diagnosis in a way parents experience as supportive.

Integrated functional genomic analyses of Klinefelter and Turner syndromes reveal global network effects of altered X chromosome dosage

In both Turner syndrome (TS) and Klinefelter syndrome (KS) copy number aberrations of the X chromosome lead to various developmental symptoms. We report a comparative analysis of TS vs. KS regarding differences at the genomic network level measured in primary samples by analyzing gene expression, DNA methylation, and chromatin conformation. X-chromosome inactivation (XCI) silences transcription from one X chromosome in female mammals, on which most genes are inactive, and some genes escape from XCI. In TS, almost all differentially expressed escape genes are down-regulated but most differentially expressed inactive genes are up-regulated. In KS, differentially expressed escape genes are up-regulated while the majority of inactive genes appear unchanged. Interestingly, 94 differentially expressed genes (DEGs) overlapped between TS and female and KS and male comparisons; and these almost uniformly display expression changes into opposite directions. DEGs on the X chromosome and the autosomes are coexpressed in both syndromes, indicating that there are molecular ripple effects of the changes in X chromosome dosage. Six potential candidate genes (RPS4X, SEPT6, NKRF, CX0rf57, NAA10, and FLNA) for KS are identified on Xq, as well as candidate central genes on Xp for TS. Only promoters of inactive genes are differentially methylated in both syndromes while escape gene promoters remain unchanged. The intrachromosomal contact map of the X chromosome in TS exhibits the structure of an active X chromosome. The discovery of shared DEGs indicates the existence of common molecular mechanisms for gene regulation in TS and KS that transmit the gene dosage changes to the transcriptome.

Genetic Landscape of Nonobstructive Azoospermia and New Perspectives for the Clinic

Nonobstructive azoospermia (NOA) represents the most severe expression of male infertility, involving around 1% of the male population and 10% of infertile men. This condition is characterised by the inability of the testis to produce sperm cells, and it is considered to have an important genetic component. During the last two decades, different genetic anomalies, including microdeletions of the Y chromosome, karyotype defects, and missense mutations in genes involved in the reproductive function, have been described as the primary cause of NOA in many infertile men. However, these alterations only explain around 25% of azoospermic cases, with the remaining patients showing an idiopathic origin. Recent studies clearly suggest that the so-called idiopathic NOA has a complex aetiology with a polygenic inheritance, which may alter the spermatogenic process. Although we are far from a complete understanding of the molecular mechanisms underlying NOA, the use of the new technologies for genetic analysis has enabled a considerable increase in knowledge during the last years. In this review, we will provide a comprehensive and updated overview of the genetic basis of NOA, with a special focus on the possible application of the recent insights in clinical practice.

Autoimmune Thyroid Disease in Specific Genetic Syndromes in Childhood and Adolescence

Autoimmune thyroid disease (ATD) is the most frequent cause of acquired thyroid dysfunction, most commonly presenting either as Hashimoto's thyroiditis or Graves' Disease. Hashimoto's thyroiditis is characterized by the presence of thyroid-specific autoantibodies, more commonly anti-thyroperoxidase antibodies in the serum and the typical inhomogeneous echostructure of the thyroid on a thyroid ultrasound examination. Hashimoto's thyroiditis can for a long time be accompanied by normal thyroid function and hypothyroidism can only progressively be established. Graves' disease is much less frequent in childhood and adolescence and presents with overt hyperthyroidism. After the onset of puberty, ATD affects females with a higher incidence than males, while during the prepubertal period there is not such a clear preponderance of affected females. ATD can occur either isolated or in the context of other autoimmune disorders, such as type 1 Diabetes mellitus (T1D), celiac disease, alopecia areata, vitiligo, etc. Especially at the pediatric age, a higher incidence of ATD is also observed in the context of specific genetic syndromes, such as trisomy 21 (Down syndrome), Klinefelter syndrome, Turner syndrome, or 22q11.2 deletion syndrome. Nevertheless, although thyroid dysfunction may also be observed in other genetic syndromes, such as Prader-Willi or Williams syndrome, the thyroid dysfunction in these syndromes is not the result of thyroid autoimmunity. Interestingly, there is emerging evidence supporting a possible link between autoimmunity and RASopathies. In this review article the incidence, as well as the clinical manifestation and accompanied pathologies of ATD in specific genetic syndromes will be presented and regular follow-up for the early identification of the disorder will be proposed.

Relative hyperestrogenism in Klinefelter Syndrome: results from a meta-analysis

OBJECTIVE

Klinefelter Syndrome (KS) is classically described as characterized by hyperestrogenism, although solid evidence is lacking. This study aims to test the hypothesis that men with KS have higher serum estradiol than normal controls.

DESIGN

Meta-analysis of all studies extracted by MEDLINE from 1942 to 31 January 2018. All studies reporting serum estradiol measurement were considered, among them only case-control studies were included in the meta-analysis.

METHODS

Meta-analysis was conducted according to the PRISMA statement using RevMan.

RESULTS

Out of 4120 articles, 23 case-control studies, 14 case series, and 19 case reports reported data on serum estradiol. A total of 707 KS and 1019 controls were included in the meta-analysis. Serum estradiol was slightly, but significantly higher in KS than controls (mean difference 4.25 pg/mL; CI: 0.41, 8.10 pg/mL; p = 0.030). This difference was lost considering only studies using estradiol assays with good accuracy (5.48 pg/mL, CI: -2.11, 13.07 pg/mL; p = 0.160). Serum testosterone and estradiol/testosterone ratio were significantly lower and higher in KS than controls, respectively. Data from KS case series and case reports confirmed that serum estradiol is within the normal ranges.

CONCLUSIONS

Serum estradiol is not increased in KS although slightly higher than controls. However, the meta-analysis that included only studies using a serum estradiol assay with good accuracy showed no difference in serum estradiol between KS and controls. The traditional belief that KS is associated with elevated serum estradiol should be reconsidered. This meta-analysis shows that men with KS have relative hyperestrogenism (increased estradiol/testosterone ratio) compared to controls.

Klinefelter syndrome: From pediatrics to geriatrics

BACKGROUND

Klinefelter syndrome (KS) is one of the major causes of nonobstructive azoospermia (NOA). Microdissection testicular sperm extraction (micro-TESE) is often performed to retrieve sperm. Infertility specialists have to care for KS patients on a lifelong basis.

METHODS

Based on a literature review and our own experience, male infertility treatment and KS pathophysiology were considered on a lifelong basis.

MAIN FINDINGS

Patients diagnosed early often have an increased number of aberrant X chromosomes. Cryptorchidism and hypospadias are often found, and surgical correction is required. Cryopreservation of testicular sperm during adolescence is an issue of debate because the sperm retrieval rate (SRR) in KS patients decreases with age. The SRR in adult KS patients is higher than that in other patients with NOA; however, low testosterone levels after micro-TESE will lower the general health and quality of life. KS men face a number of comorbidities, such as malignancies, metabolic syndrome, diabetes, cardiovascular disease, bone disease, and immune diseases, which ultimately results in increased mortality rates.

CONCLUSION

A deeper understanding of the pathophysiology of KS and the histories of KS patients before they seek infertility treatment, during which discussions with multidisciplinary teams are sometimes needed, will help to properly treat these patients.

Klinefelter Syndrome: Clinical Spectrum Based on 44 Consecutive Cases from a South Indian Tertiary Care Center

BACKGROUND

Klinefelter syndrome (KFS) is the commonest chromosomal abnormality, yet remains largely underdiagnosed due to its varied clinical presentation. This study was done to understand the clinical spectrum in our population.

AIM

We intended to study the clinical characteristics of children and adults with KFS in our population. We also desired to identify any special features of Klinefelter variants.

METHODS

Forty-four patients with karyotype diagnosis of KFS during the time period 2007-2015 were included in this retrospective study. Clinical details and hormonal profile were obtained from hospital information system.

RESULTS

Our study population consisted of 17 (38.6%) participants in pediatric age group (age <18 years) and 27 (61.4%) adults. Clinical presentation prompting evaluation in the former group included cardiac anomalies (29.4%), dysmorphism (23.5%), hypogonadism (17.6%), developmental delay (11.8%), tall stature (11.8%), and cryptorchidism (5.9%). Among adults, 16 (59.2%) presented with hypogonadism and 9 (20.4%) had primary infertility. Six children (35.3%) had micropenis and four (three children, one adult) had unilateral undescended testis. Behavioral problems were detected in 19 (43.2%) subjects. Mean follicle stimulating hormone (FSH) and luteinizing hormone (LH) values were 38 IU/mL and 18 IU/mL, respectively. The classical 47 XXY karyotype was detected in 38 (86.4%) subjects and 6 (13.6%) had karyotype consistent with Klinefelter variants.

CONCLUSION

KFS was diagnosed only after 18 years of age in two-thirds of patients. Developmental delay, cardiac anomalies, behavioral abnormalities, and intellectual disabilities were the common presentations in pediatric subjects. Adults predominantly presented with hypogonadism. Individuals with Klinefelter variant karyotype sought medical attention predominantly for non-gonadal concerns.

Management of cardiovascular complications in Klinefelter syndrome patients

INTRODUCTION

Klinefelter syndrome (KS), also known as 47, XXY, shows increased mortality when compared with mortality rates among the general population. Cardiovascular, hemostatic, metabolic diseases are implicated. Moreover, cardiac congenital anomalies in KS can contribute to the increase in mortality.

AREAS COVERED

In this study, we have systematically reviewed the relationships between KS and the cardiovascular system and the management of cardiovascular complication. In summary, patients with KS display increased cardiovascular risk profile, characterized by increased prevalence of metabolic alterations including dyslipidemia, diabetes mellitus (DM), and abnormalities in biomarkers of cardiovascular disease. KS subjects are characterized by subclinical abnormalities in endothelial function and in left ventricular (LV) systolic and diastolic function, which - when associated with chronotropic incompetence - may negatively influence cardiopulmonary performance. Moreover, KS patients appear to be at a higher risk for cardiovascular disease, due to thromboembolic events with high prevalence of recurrent venous ulcers, venous insufficiency, recurrent venous and arterial thromboembolism leading to deep venous thrombosis or pulmonary embolism.

EXPERT OPINION

Considering the unequivocal finding of increased mortality of KS patients, we suggest a periodic cardiovascular follow up in specialized centers with multidisciplinary care teams that comprise endocrinologists and cardiologists dedicated to KS syndrome.

Delivering the Diagnosis of Sex Chromosome Aneuploidy: Experiences and Preferences of Parents and Individuals

Increased prenatal diagnoses of sex chromosome aneuploidies (SCAs) amid limited knowledge of their prognoses heighten the need to understand how families contend with the implications of an SCA. To explore the experiences of parents and individuals who received a genetic diagnosis of an SCA (excluding Turner syndrome), we conducted semistructured qualitative telephone interviews with 43 participants affected by these conditions. Parents (n = 35) and individuals (n = 8) expressed almost unanimous interest in more optimistic portrayals of their condition from their providers, even when the prognosis is uncertain. While some participants reported success in receiving accurate information from their provider and identifying supportive resources, numerous families received outdated or misleading information about their condition and lacked direction in accessing follow-up care and support. Parents desire greater coordination of their child's medical care and access to care that approaches an SCA holistically. Opportunities remain to improve the diagnosis and care of individuals with SCAs.

A Search for Disorders of Sex Development among Infertile Men

A retrospective cross-sectional study was performed in a DSD clinic at a tertiary service (University Hospital) to estimate the frequency of disorders of sex development (DSD) among men who seek medical care because of infertility. The sample included 84 men >20 years of age referred from 2010-2017 due to oligozoospermia or nonobstructive azoospermia of unknown etiology. Twelve cases (14%) were diagnosed as DSD, including Klinefelter Syndrome, 46,XX testicular DSD, and mild androgen insensitivity syndrome. Y chromosome microdeletions were detected in 2 patients. Among the remaining 70 cases there were patients with chromosome abnormalities which are not included in the DSD classification as well as rare NR5A1 variants of uncertain significance and hypergonadotropic hypogonadism and microorchidism in 46,XY subjects. In conclusion, the frequency of DSD in this study was 14%, consisting mainly of sex chromosome abnormalities but also 46,XX and 46,XY DSD. However, this figure may increase as further investigations are conducted in idiopathic cases with signs of primary testicular failure, which may present partial gonadal dysgenesis.

sEst: Accurate Sex-Estimation and Abnormality Detection in Methylation Microarray Data

DNA methylation influences predisposition, development and prognosis for many diseases, including cancer. However, it is not uncommon to encounter samples with incorrect sex labelling or atypical sex chromosome arrangement. Sex is one of the strongest influencers of the genomic distribution of DNA methylation and, therefore, correct assignment of sex and filtering of abnormal samples are essential for the quality control of study data. Differences in sex chromosome copy numbers between sexes and X-chromosome inactivation in females result in distinctive sex-specific patterns in the distribution of DNA methylation levels. In this study, we present a software tool, sEst, which incorporates clustering analysis to infer sex and to detect sex-chromosome abnormalities from DNA methylation microarray data. Testing with two publicly available datasets demonstrated that sEst not only correctly inferred the sex of the test samples, but also identified mislabelled samples and samples with potential sex-chromosome abnormalities, such as Klinefelter syndrome and Turner syndrome, the latter being a feature not offered by existing methods. Considering that sex and the sex-chromosome abnormalities can have large effects on many phenotypes, including diseases, our method can make a significant contribution to DNA methylation studies that are based on microarray platforms.

Chromosomal disorders: estimating baseline birth prevalence and pregnancy outcomes worldwide

Chromosomal disorders, of which Down syndrome is the most common, can cause multi-domain disability. In addition, compared to the general population, there is a higher frequency of death before the age of five. In many settings, large gaps in data availability have hampered policy-making, programme priorities and resource allocation for these important conditions. We have developed methods, which overcome this lack of data and allow estimation of the burden of affected pregnancies and their outcomes in different settings worldwide. For example, the methods include a simple equation relating the percentage of mothers 35 and over to Down syndrome birth prevalence. The results obtained provide a starting point for consideration of services that can be implemented for the care and prevention of these disorders.

Klinefelter Syndrome: Integrating Genetics, Neuropsychology, and Endocrinology

Although first identified over 70 years ago, Klinefelter syndrome (KS) continues to pose substantial diagnostic challenges, as many patients are still misdiagnosed, or remain undiagnosed. In fact, as few as 25% of patients with KS are accurately diagnosed and most of these diagnoses are not made until adulthood. Classic characteristics of KS include small testes, infertility, hypergonadothropic hypogonadism, and cognitive impairment. However, the pathophysiology behind KS is not well understood, although genetic effects are also thought to play a role. For example, recent developments in genetics and genomics point to a fundamental change in our understanding of KS, with global epigenetic and RNA expression changes playing a central role for the phenotype. KS is also associated with more general health markers, including higher morbidity and mortality rates and lower socioeconomic status (which likely affect both morbidity and mortality). In addition, hypogonadism is associated with greater risk of metabolic syndrome, type 2 diabetes, cardiovascular disease, breast cancer, and extragonadal germ cell tumors. Medical treatment typically focuses on testosterone replacement therapy (TRT), although the effects of this therapy have not been studied rigorously, and future studies need to evaluate the effects of TRT on metabolic risk and neurocognitive outcomes. This review presents a comprehensive interdisciplinary examination of recent developments in genetic, endocrine, and neurocognitive science, including the study of animal models. It provides a number of recommendations for improving the effectiveness of research and clinical practice, including neonatal KS screening programs, and a multidisciplinary approach to KS treatment from childhood until senescence.

Caring for individuals with a difference of sex development (DSD): a Consensus Statement

The term differences of sex development (DSDs; also known as disorders of sex development) refers to a heterogeneous group of congenital conditions affecting human sex determination and differentiation. Several reports highlighting suboptimal physical and psychosexual outcomes in individuals who have a DSD led to a radical revision of nomenclature and management a decade ago. Whereas the resulting recommendations for holistic, multidisciplinary care seem to have been implemented rapidly in specialized paediatric services around the world, adolescents often experience difficulties in finding access to expert adult care and gradually or abruptly cease medical follow-up. Many adults with a DSD have health-related questions that remain unanswered owing to a lack of evidence pertaining to the natural evolution of the various conditions in later life stages. This Consensus Statement, developed by a European multidisciplinary group of experts, including patient representatives, summarizes evidence-based and experience-based recommendations for lifelong care and data collection in individuals with a DSD across ages and highlights clinical research priorities. By doing so, we hope to contribute to improving understanding and management of these conditions by involved medical professionals. In addition, we hope to give impetus to multicentre studies that will shed light on outcomes and comorbidities of DSD conditions across the lifespan.