Advances in the Interdisciplinary Care of Children with Klinefelter Syndrome

Research Priorities of Individuals and Families with Sex Chromosome Aneuploidies

Sex chromosome aneuploidies (SCAs) are chromosomal variations that result from an atypical number of X and/or Y chromosomes. Combined, SCAs affect ~1/400 live births, including individuals with Klinefelter syndrome (47,XXY), Turner syndrome (45,X and variants), Double Y syndrome (47,XYY), Trisomy X (47,XXX), and rarer tetrasomies and pentasomies. Individuals with SCAs experience a wide variety of physical health, mental health, and healthcare experiences that differ from the standard population. To understand the priorities of the SCA community we surveyed participants in two large SCA registries, the Inspiring New Science in Guiding Healthcare in Turner Syndrome (INSIGHTS) Registry and the Generating Advancements in Longitudinal Analysis in X and Y Variations (GALAXY) Registry. 303/629 (48.1% response rate) individuals from 13 sites across the United States responded to the survey, including 251 caregivers and 52 self-advocates, with a range of ages from 3 weeks to 73 years old and represented SCAs including Turner syndrome, XXX, XXY, XYY, XXYY, and combined rare tetrasomies and pentasomies. Results demonstrate the priorities for physical health and emotional/behavioral health identified by the SCA community, as well as preferred types of research. All SCA subtypes indicated intervention studies as the top priority, emphasizing the need for researchers to focus on clinical treatments in response to priorities of the SCA community.

STATEMENTS RELATING TO ETHICS AND INTEGRITY POLICIES

The data that support the findings of this study are available on request from the corresponding author. This study was funded by the Turner Syndrome Global Alliance, Association for X and Y Chromosome Variations, Living with XXY, the XXYY Project, and the University of Colorado School of Medicine Department of Pediatrics. Data collection and storage was supported by NIH/NCATS Colorado CTSA Grant Number UM1 TR004399. The authors do not have any conflicts of interest to disclose. This study was reviewed and approved by the Colorado Multiple Institutional Review Board (COMIRB # 20-0482 and # 19-3027). All participants provided informed consent for participation - participants under 18 years old provided assent along with parental informed consent prior to any study procedures. Contents are the authors' sole responsibility and do not necessarily represent official NIH views.

Communication of the diagnosis to Klinefelter subjects: an observational study on a key moment of the patient's life

PURPOSE

Klinefelter syndrome (KS) is the most prevalent sex chromosome disorder among males. The communication of the KS diagnosis holds significant implications for the diagnosis's acceptance. Recently, the increased use of prenatal diagnostic procedures has raised the question of whether, when, and by whom information, once provided to parents, should be communicated to their children/adolescents. Currently, there is limited information on this topic. This study aims to investigate the most suitable timing, content, and healthcare professionals (HCPs) according to KS patients' suggestions for conveying the diagnosis, analyzing the impact of communicating the KS diagnosis on patients and their reception of the communication in real-life situations. Furthermore, research entails a comparison of the actual communication and the patients' preferred mode of communication.

METHODS

Self-reported interview data was collected from 196 adults diagnosed with KS. The interview was structured, consisting of 32 multiple-choice questions covering various areas related to diagnosis communication.

RESULTS

Most patients with Klinefelter syndrome reported that earlier communication would have been beneficial. Communication before the age of 18 and by parents increased the likelihood of overcoming negative consequences and relying on psychological support.

CONCLUSION

To mitigate the adverse effects of poorly timed and inadequately delivered communication, typically by a single person, it is advisable that such communication be carried out at the onset of adolescence by an interdisciplinary team of HCPs (including psychologists, geneticists, endocrinologists) and parents. The information provided should not solely concentrate on hormonal and fertility aspects, but also consider other factors such as psychological variables.

Achalasia in Klinefelter syndrome: A suspected pediatric case as well as prevalence analysis suggesting increased risk in this population

A 4-year-old male with Klinefelter syndrome (KS), speech delay, and intermittent history of coughing and choking during meals was referred for evaluation. Prior evaluation with computed tomography showed a dilated esophagus at the gastroesophageal junction. The patient was unable to tolerate a barium swallow. Upper endoscopy was performed, and an intraoperative esophagogram, demonstrated a "birds beak" appearance suggestive of achalasia. There is no documented relationship between achalasia and KS. However, we utilized TriNetX (a large-scale data clearinghouse) to demonstrate a higher prevalence of achalasia in patients with KS as compared to the general population.

Klinefelter Syndrome Diagnosis Masked by Opioid Use Disorder

Klinefelter syndrome (KS) is a chromosomal disorder characterized by the presence of an extra X chromosome in males (47, XXY). Individuals with KS often exhibit a range of physical, cognitive, and behavioral symptoms, including tall stature, gynecomastia, reduced libido, and varying degrees of infertility. A major diagnostic challenge arises when individuals with KS exhibit symptoms that are obscured by comorbid conditions, such as opioid use disorder (OUD). Individuals with OUD or psychiatric disease may exhibit symptoms similar to those of KS. Misattribution of symptoms can lead to delayed or missed diagnosis of Klinefelter's syndrome, underscoring the importance of a thorough evaluation, particularly in the presence of substance use disorders. In this case report, we illustrate the diagnostic challenges posed by OUD in a 39-year-old male patient with a unique case of undiagnosed KS.

Evidence-based recommendations for delivering the diagnosis of X & Y chromosome multisomies in children, adolescents, and young adults: an integrative review

BACKGROUND

The diagnosis of supernumerary X & Y chromosome variations has increased following the implementation of genetic testing in pediatric practice. Empirical evidence suggests that the delivery of the diagnosis has a lasting impact on how affected individuals and their parents perceive and adapt to the diagnosis. The purpose of this review is to synthesize the literature to obtain useful recommendations for delivering a pediatric diagnosis of a sex chromosome multisomy (SCM) based upon a growing body of quantitative and qualitative literature on patient experiences.

METHODS

We conducted an integrative literature review using PubMed, Web of Science and CINAHL employing keywords "genetic diagnosis delivery," "genetic diagnosis disclosure," "sex chromosome aneuploidy," "Klinefelter syndrome" or ""47, XXY," "Jacob syndrome" or "47, XYY," "Trisomy X," "Triple X" or "47, XXX," and "48 XXYY from January 1, 2000, to October 31, 2023.

RESULTS

Literature supports that patients and parents value the provision of up-to-date information and connection with supportive resources. Discussion of next steps of care, including relevant referrals, prevents perceptions of provider abandonment and commitment to ongoing support. Proactively addressing special concerns such as disclosing the diagnosis to their child, family, and community is also beneficial. Tables are provided for useful information resources, medical specialties that may be required to support patients, and common misconceptions that interfere with accurate information about the diagnosis.

CONCLUSION

Patient experiences suggest there should be heightened attention to diagnosis delivery, in reference to the broader ethical and social impacts of a SCM diagnosis. We present recommendations for optimal disclosure of a SCM diagnosis in early and late childhood, adolescence, and young adulthood.

Healthcare and support experiences of adolescents and young adults diagnosed with 47,XXY, 47,XXX, and 48,XXYY

Sex chromosome aneuploidies (SCAs) are among the most common chromosomal conditions. There is little scholarship on how adolescents and young adults (AYAs) affected by SCA engage with and adapt to their diagnosis. In order to understand how AYAs adapt to a SCA diagnosis, we conducted a secondary analysis of qualitative interviews with AYAs. Eight in-depth semi-structured interviews with individuals with a diagnosis of 47,XXY, 47,XXX, and 48,XXYY were analyzed for iterative themes related to adaptation to a SCA diagnosis in accordance with standard qualitative methodology. Our findings suggest that the process of adaptation is highly variable and complex and is mediated by external factors including diagnosis delivery and community support. Factors associated with adaptation include feeling understood and supported by healthcare providers; researching the condition; receiving hormone replacement therapy; and receiving support from a community of peers. As access to prenatal and pediatric genetic testing continues to expand, non-genetic pediatric providers are increasingly likely to interact with individuals with SCAs as part of their initial diagnostic odyssey or ongoing medical management. Understanding the diversity of lived experiences of AYAs with SCAs is helpful for healthcare providers to facilitate holistic care and provide meaningful support to patients.

Generation of iPSC Cell Lines from Patients with Sex Chromosome Aneuploidies

Somatic cell reprogramming allows the generation of human induced pluripotent stem cells (iPSCs) from patient's cells. The derived iPSCs provide an unlimited source of patient-specific cells that can be virtually differentiated in any cell of the human body. The generation of iPSCs has important implications for all human medicine fields, as they can be used for drug discovery, regenerative medicine, and developmental studies. Klinefelter Syndrome (KS) is the most common chromosome aneuploidy in males. KS is typically characterized by a 47,XXY karyotype, representing 80-90% of KS patients. In rare cases, high-grade sex chromosome aneuploidies (SCAs), 48,XXXY; 48,XXYY; 49,XXXXY, are also observed in males. Since the advent of the reprogramming technique, a few KS-iPSCs have been described. Here, we detail the methodology for generating primary fibroblasts from patients' skin biopsies and the subsequent derivation of iPSCs using an efficient integrative-free mRNA-based somatic reprogramming approach.

Quality of life in men with Klinefelter syndrome: a multicentre study

Background

Klinefelter syndrome (KS) is associated with an increased risk of lower socioeconomic status and a higher risk for morbidity and mortality, which may have a significant impact on quality of life (QOL). The objective of this study is to investigate QOL in a large European cohort of men with KS.

Design

Cross-sectional multicentre study.

Methods

Two-hundred-eighteen men with KS were recruited from 14 clinical study centres in 6 European countries which participated in the European dsd-LIFE study. Male normative data from a healthy and a psychiatric reference population were used for comparison. The validated World Health Organization (WHO) QOL (WHOQOL)-BREF questionnaire was used to investigate five main domains of quality of life (WHOQOL): global, physical, psychological, environment, and social.

Results

The QOL physical domain score was lower for men with KS compared to the healthy reference population (KS: 66.9; s.d. 19.4, n = 193; healthy reference population: 76.5; s.d. 16.2, n = 1324, P < 0.001) but higher compared to the psychiatric reference population (54.6; s.d. 20.6; n = 77, P < 0.001). The WHOQOL-psychological domain score was lower for men with KS compared to the healthy reference population (KS: 63.6; s.d. 17.8, n = 193; healthy reference population: 67.8; s.d. 15.6, n = 1324, P < 0.05) but higher compared to the psychiatric reference population (45.9; s.d. 26.0), n = 77, P < 0.001). The social domain score on the WHOQOL questionnaire was found to be lower in men with Klinefelter syndrome (KS) compared to the healthy reference population (KS: 60.0; s.d. 21.6, n = 193; healthy reference population: 68.2; s.d. 13.8, n = 1324, P < 0.001). However, this score was similar to that of the psychiatric reference population (61.0; s.d. 17.0, n = 77, P = 0.5). The WHO environment domain score of men with KS (70.0; s.d. 15.0, n = 193) was similar to the healthy reference population (70.5; s.d. 20.7, n = 1324) but higher compared to the psychiatric reference population (61.9; s.d. 20.8, n = 77, P = 0.002). Experienced discrimination, less social activities, and the presence of chronic health problems were associated with significantly decreased QOL in men with KS.

Conclusion

Overall QOL in European men with KS is significantly worse compared to a healthy European reference population. Especially, the presence of discrimination, less social activities, and chronic health problems is associated with lower physical, psychological, and social QOL. Further studies are necessary to investigate if a multidisciplinary approach may help to provide adequate counselling and psychosocial support to improve QOL.

Sex chromosome aneuploidies and fertility: 47,XXY, 47,XYY, 47,XXX and 45,X/47,XXX

The overall incidence of sex chromosome aneuploidies is approximately 1 per 500 live-born infants, but far more common at conception. I shall review the fertility aspects of the sex chromosome trisomies, XXY, XYY, and XXX, with special reference to the karyotype 45,X/47,XXX. Each has a 'specific' (but variable) phenotype but may be modified by mosaicism. Although the alterations in the hypothalamic-pituitary-gonadal axis are important (and discussed), the emphasis here is on potential fertility and if one might predict that at various epochs within an individual's life span: fetal, 'mini'-puberty, childhood, puberty, and adulthood. The reproductive axis is often affected in females with the 47,XXX karyotype with diminished ovarian reserve and accelerated loss of ovarian function. Fewer than 5% of females with Turner syndrome have the 45,X/47,XXX karyotype. They have taller stature and less severe fertility issues compared to females with the 45,X or other forms of Turner syndrome mosaicism. For the 47,XXY karyotype, non-obstructive azoospermia is almost universal with sperm retrieval by micro-testicular sperm extraction possible in slightly fewer than half of the men. Men with the 47,XYY karyotype have normal to large testes and much less testicular dysfunction than those with the 47,XXY karyotype. They do have a slight increase in infertility compared to the reference population but not nearly as severe as those with the 47,XXY karyotype. Assisted reproductive technology, especially micro-testicular sperm extraction, has an important role, especially for those with 47,XXY; however, more recent data show promising techniques for the in vitro maturation of spermatogonial stem cells and 3D organoids in culture. Assisted reproductive technology is more complex for the female, but vitrification of oocytes has shown promising advances.

Klinefelter syndrome: going beyond the diagnosis

Although Klinefelter syndrome (KS) is common, it is rarely recognised in childhood, sometimes being identified with speech or developmental delay or incidental antenatal diagnosis. The only regular feature is testicular dysfunction. Postnatal gonadotropin surge (mini-puberty) may be lower, but treatment with testosterone needs prospective studies. The onset of puberty is at the normal age and biochemical hypogonadism does not typically occur until late puberty. Testosterone supplementation can be considered then or earlier for clinical hypogonadism. The size at birth is normal, but growth acceleration is more rapid in early and mid-childhood, with adult height greater than mid-parental height. Extreme tall stature is unusual. The incidence of adolescent gynaecomastia (35.6%) is not increased compared with typically developing boys and can be reduced or resolved by testosterone supplementation, potentially preventing the need for surgery. Around two-thirds require speech and language therapy or developmental support and early institution of therapy is important. Provision of psychological support may be helpful in ameliorating these experiences and provide opportunities to develop strategies to recognise, process and express feelings and thoughts. Boys with KS are at increased risk of impairment in social cognition and less accurate perceptions of social emotional cues. The concept of likely fertility problems needs introduction alongside regular reviews of puberty and sexual function in adolescents. Although there is now greater success in harvesting sperm through techniques such as testicular sperm extraction, it is more successful in later than in early adolescence. In vitro maturation of germ cells is still experimental.

Klinefelter Syndrome: What should we tell prospective parents?

Klinefelter syndrome (KS) or 47,XXY is the most common sex chromosome aneuploidy (SCA), occurring at a prevalence of 1 in 600 male pregnancies. Historically, only 25% of individuals with KS came to medical attention, for a range of issues across the life course including under-virilisation at birth, developmental and social concerns in childhood, absence, delay or arrest of puberty in adolescence or infertility in adulthood. Our understanding of the phenotypic spectrum of KS has been largely influenced by this ascertainment bias. With increasing uptake of antenatal noninvasive prenatal testing (NIPT), a corresponding increase in identification of KS has been documented. Population-based longitudinal data from infancy to adulthood on these individuals is lacking, which impedes balanced antenatal genetic counselling and raises issues for prospective parents and clinicians alike.

Facilitating the transition from paediatric to adult care in endocrinology: a focus on growth disorders

PURPOSE OF REVIEW

Many childhood-onset growth disorders (COGDs) require continued care into adulthood, and the time of transition between paediatric and adult providers carries a high risk for interruptions in medical care and consequent worsening of disease management.

RECENT FINDINGS

Research into best practices for healthcare transition (HCT) describes three distinct stages. Stage 1, transition planning and preparation, begins in the paediatric setting during early adolescence and ensures that the patient has adequate medical knowledge, self-management skills, and readiness for transition. Stage 2, transfer to adult care, occurs with variable timing depending on transition readiness and is best facilitated by warm hand-offs and, when possible, joint visits with the paediatric and adult provider(s) and/or involvement of a care coordinator. Stage 3, intake and integration into adult care, entails retaining the patient in the adult setting, ideally through the involvement of a multidisciplinary approach.

SUMMARY

This review covers general principles for ensuring smooth transition of adolescents and young adults (AYA) with COGD, disease-specific medical considerations for paediatric and adult endocrinologists during the transition process, and general and disease-specific resources to assess transition readiness and facilitate transition.

State-wide increase in prenatal diagnosis of klinefelter syndrome on amniocentesis and chorionic villus sampling: Impact of non-invasive prenatal testing for sex chromosome conditions

BACKGROUND

To analyze population-based trends in the prenatal diagnosis of sex chromosome aneuploidy (SCA) since the availability of non-invasive prenatal testing (NIPT).

METHODS

Retrospective state-wide data for all prenatal diagnoses performed <25 weeks gestation from 2005 to 2020 in Victoria, Australia. Non-invasive prenatal testing became locally available from 2012. The prenatal diagnosis rates of SCA as proportions of all prenatal diagnostic tests and all births were calculated. Statistical significance was assessed with the χ2 test for trend, with p < 0.05 considered significant.

RESULTS

46,518 amniocentesis and chorionic villus sampling were performed during the study period, detecting 617 SCAs. There was a significant increase in the rate of prenatal SCAs from 5.8 per 10,000 births in 2005 to 8.7 per 10,000 births in 2020 (p < 0.0001). This increase was predominantly due to 47,XXY cases, 91% of which were ascertained via positive NIPT for this condition in 2020. The prenatal diagnosis rate of 47,XXY significantly increased from 0.8 per 10,000 births in 2005 to 4.3 per 10,000 births in 2020 (p < 0.0001).

CONCLUSION

Screening for SCAs using NIPT has directly led to an increase in their prenatal diagnosis on a population-wide basis, especially 47,XXY. This has implications for clinician education, genetic counselling, and pediatric services.

Prenatal diagnosis of sex chromosome aneuploidy-What do we tell the prospective parents?

Sex chromosome aneuploidy (SCA) can be detected on prenatal diagnostic testing and cell free DNA screening (cfDNA). High risk cfDNA results should be confirmed with diagnostic testing. This summary article serves as an update for prenatal providers and assimilates data from neurodevelopmental, epidemiologic, and registry studies on the most common SCA. This information can be helpful for counseling after prenatal diagnosis of sex chromosome aneuploidy. Incidence estimates may be influenced by ascertainment bias and this article is not a substitute for interdisciplinary consultation and counseling.

The impact of Klinefelter syndrome on socioeconomic status: a multicenter study

Klinefelter syndrome (KS) is associated with an increased risk of neuropsychological morbidity, such as learning disabilities, which may have a significant impact on socioeconomic status (SES). The objective of this study was to investigate the SES in men with KS and to associate this outcome with social participation, age at diagnosis, testosterone therapy and physical and mental health status. Men with KS were recruited in 14 clinical study centers in six European countries which participated in the European dsd-LIFE study. Two hundred five men with KS were eligible for inclusion. Male normative data from the European Social Surveys (ESS) were used for comparison. Data related to education, occupation, satisfaction with income and householding were collected. Compared to the ESS reference population, fewer men with KS achieved a high level of education (13% vs 25%, P < 0.001). There was a significant difference in having a paid job (55% vs 66%, P < 0.001), and the percentage of absence by sickness or disability was higher among men with KS (10% vs 3%, P < 0.001). Furthermore, satisfaction with current household's income was lower (32% vs 42%, P < 0.01). Lower scores for subjective general health were associated with lower scores for these outcomes. Men with KS achieve on average lower levels of education, occupation and report less satisfaction with income compared to the ESS reference population. The presence of health problems and lower scores of subjective general health was related to lower levels of occupation and lower satisfaction with income in men with KS.

Prenatal Diagnosis of Chromosomal Mosaicism in Over 18,000 Pregnancies: A Five-Year Single-Tertiary-Center Retrospective Analysis

Background: Chromosomal mosaicism (CM) is a common biological phenomenon observed in humans. It is one of the main challenges in prenatal diagnosis due to uncertain outcomes, especially when fetal ultrasonographic features appear normal. This study aimed to assess the phenotypic features of CM detected during prenatal diagnosis and the risk factors affecting parents’ pregnancy decisions.

Materials and methods: A retrospective cohort study involving 18,374 consecutive pregnancies that underwent prenatal diagnosis by karyotyping, fluorescence in situ hybridization (FISH), or chromosome microarray analysis (CMA) was conducted. The association of risk factors with malformations detected by ultrasound and pregnancy outcomes was assessed using the chi-square test and binary logistic regression. Discordant results between the different methods were identified and further analyzed.

Results: During this five-year period, 118 (0.6%) patients were diagnosed with CM. The incidences of CM in the chorionic villus, amniotic fluid, and umbilical cord blood were 3.2, 0.5, and 0.7%, respectively. The frequency of ultrasound malformations in individuals with a high fraction of autosomal CM was significantly higher than that in other groups (62.5% vs. 21.4–33.3%, all p <0.05). Inconsistent results between karyotyping and CMA/FISH were observed in 23 cases (19.5%). The risk of pregnancy termination in cases with ultrasound malformations, consistent results, autosomal CM, or a high CM fraction increased with an odds ratio of 3.09, 8.35, 2.30, and 7.62 (all p <0.05). Multiple regression analysis revealed that all four factors were independent risk factors for the termination of pregnancy.

Conclusion: Patients with a high fraction of autosomal CM are more likely to have ultrasound malformations. Inconsistent results between different methods in CM are not rare. Ultrasound malformations, consistent results between different methods, autosomal CM, and a high CM fraction were independent risk factors for the choice to terminate pregnancies.

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.

Communicating the diagnosis of Klinefelter syndrome to children and adolescents: when, how, and who?

Klinefelter syndrome (KS) is the most frequent sex chromosome aneuploidy in males. KS diagnosis disclosure has an important impact on diagnosis acceptance and the increase in prenatal diagnostic procedures raises questions regarding communication to children/adolescents. Limited data are currently available on this issue. The aim of the study was to investigate aspects like the best timing (when), topics (how), and healthcare professional (who), which, in the opinion of both KS patients and parents, may be considered the best for diagnosis communication to KS children/adolescents. We also analyzed how participants received the communication in real life and evaluated the differences between the responses given by parents who receive KS diagnosis before or after KS patient birth regarding disclosure of KS communication. KS adult patients, KS mothers, and KS fathers, not belonging to the same family, completed a questionnaire containing quantitative measures (5 points Likert scale), open-ended questions, and multiple choice questions. Parental responses were divided according to the timing at which the communication occurred: prenatal age diagnosis (PRE-D) or postnatal age diagnosis (POST-D). A total of 41 KS adults and 77 KS parents (53 PRE-D, 24 POST-D) were recruited. Most KS patients and most POST-D parents consider that communication should be provided before 14 years of age; most PRE-D parents consider 14–18 years of age the best period for communication. We suggest that communication should occur preferably before 18 years of age by a multidisciplinary team (endocrinologists, psychologists, geneticists, and parents) and that the information should deal not only fertility and hormonal aspects but also metabolic and cognitive features.

Toward a potential association between eosinophilic esophagitis and Klinefelter syndrome: a case series and review of the literature

Klinefelter syndrome (KS) is a sex aneuploidy abnormality comprised by one additional X chromosome. It occurs in 1:500-1000 male births. As with women, an increased susceptibility to autoimmune diseases is present. We report three cases of coexisting EoE and KS for a prevalence of 2% in our EoE clinic. Possible changes in gene expression in KS are reviewed, some of which may be related to activation of genes located on the X chromosome. We postulate that these X-activated genes in patients with KS yield a greater likelihood of developing EoE because of their genetic predisposition to autoimmune diseases.

In-vivo skeletal muscle mitochondrial function in Klinefelter syndrome

Klinefelter syndrome (XXY) occurs in 1 in 600 males, resulting in testosterone deficiency and a high prevalence of insulin resistance. Testosterone deficiency in men is a known cause of insulin resistance, and mitochondrial dysfunction is hypothesized to mediate this relationship. The aim of this cross-sectional study was to evaluate muscle mitochondrial function in XXY compared with male controls. Twenty-seven boys with XXY (age 14.7±1.8 years) were compared with 87 controls (age 16.9±0.9). In-vivo calf muscle mitochondrial function was assessed via phosphorus magnetic resonance spectroscopy (³¹P-MRS) following 90 s of isometric 70% maximal exercise. Multiple linear regression was used to compare ³¹P-MRS outcomes (ADP and phosphocreatine (PCr) time constants, rate of oxidative phosphorylation (Oxphos), and Q_max or the maximal mitochondrial function relative to mitochondrial density) between groups after adjusting for age differences. There were no statistically significant differences in the mitochondrial outcomes of ADP, Oxphos, PCr, and Q_max between the groups. There were also no differences in a sensitivity analysis within the XXY group by testosterone treatment status. In this study, in-vivo postexercise skeletal muscle mitochondrial function does not appear to be impaired in adolescents with XXY compared with controls and is not significantly different by testosterone treatment status in XXY.

Rehabilitation of ectodermal dysplasia patient with a telescopic denture in the maxilla and mandibular implant assisted overdenture: A case report

Hypohidrotic ectodermal dysplasia is a heritable disease, characterized by hypodontia, hypotrichosis, and anhidrosis. This clinical report demonstrates prosthetic rehabilitation of a patient complaining of impaired mastication and the odd appearance of her jaws. Maxillary telescopic overdenture and implant-supported mandibular prostheses were fabricated to improve mastication, speech, and esthetics of the patient.

Medulla oblongata germinoma with Klinefelter syndrome

Intracranial germinomas mostly occur in teenagers and young adults. The common sites are pineal and suprasellar regions. Males with Klinefelter syndrome, compared with males without chromosomal abnormalities, are known to have a higher incidence of developing pineal or suprasellar germinomas. As for germinoma in the medulla oblongata, this is rare, with only 21 previous cases reported. Due to the rarities, any relationship between people with Klinefelter syndrome and medulla oblongata germinomas remains undetermined. We present a rare case of medulla oblongata germinoma in a 25-year-old man. It is the second case of medulla oblongata germinoma in association with Klinefelter syndrome. We emphasize the importance of karyotyping in every case of germinoma, especially those with intracranial germinomas at atypical locations.

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.

Association between Down Syndrome and Disorders of Sex Development: Report of Three Cases and Review of 188 Cases in the Literature

In this study, we present 3 cases of Down syndrome (DS) associated with disorders/differences of sex development (DSD) and review the literature on this topic. Case 1: 1-year-old child with male genitalia and DS phenotype, 47,XX,+21 karyotype and testicular DSD. Case 2: 11-month-old child with male genitalia and few DS dysmorphisms, 45,X/47,XY,+21 karyotype, and mixed gonadal dysgenesis. Case 3: 4-month-old child with female genitalia and DS phenotype, 47,XY,+21 karyotype and XY complete gonadal dysgenesis. In the literature, among 188 patients, 107 (57%) had Klinefelter syndrome and 61 (33%) Turner syndrome, 12 (6%) had mixed gonadal dysgenesis, 2 (1%) had partial androgen insensitivity, 2 (1%) ovotesticular DSD, and the others had congenital adrenal hyperplasia, XY partial gonadal dysgenesis, XY complete gonadal dysgenesis, and complete androgen insensitivity (1 case each). A typical DS phenotype was found in all individuals of the revision, with the exception of one case, but DSD features were not always reported. In conclusion, the association of DS with sex chromosome DSD is the most frequently observed, whereas associations with 46,XX and 46,XY DSD is extremely rare.

At what age should we attempt to retrieve sperm from males with Klinefelter syndrome

Klinefelter syndrome (KS) is a common disorder and almost every clinician in almost every sub-specialty of medicine will knowingly or unwittingly treat boys or men with a 47,XXY chromosomal constitution. Although there are numerous aspects of KS worthy of discussion, this contribution will focus specifically on the controversial, and as yet unresolved, issue of whether it is advantageous to harvest testis tissue from peri-pubertal or adolescent boys with KS in a heroic effort to preserve that child’s chances of reproduction in his future adult life. What would be the rationale for that, how does the biology of spermatogenesis in the Klinefelter testis impact that decision, and what does the data show? The answer, assembled from a selection of seemingly disparate sources and directions, appears to be “No”. We do not have to advocate for an aggressive approach, we do not have to preemptively preserve future fertility. We can justifiably wait until adulthood with equivalent chances of success.

The Impact and Management of Gynaecomastia in Klinefelter Syndrome

Gynecomastia is defined as a palpable enlargement of the male breast, secondary to an increase in the glandular and stromal breast tissue. Gynecomastia is encountered in up to 80% of Klinefelter syndrome cases. The pathophysiology involves testosterone/estrogen imbalance. This review article will further explore the pathophysiology of gynecomastia along with the different lines of management.

European academy of andrology guidelines on Klinefelter Syndrome Endorsing Organization: European Society of Endocrinology

BACKGROUND

Knowledge about Klinefelter syndrome (KS) has increased substantially since its first description almost 80 years ago. A variety of treatment options concerning the spectrum of symptoms associated with KS exists, also regarding aspects beyond testicular dysfunction. Nevertheless, the diagnostic rate is still low in relation to prevalence and no international guidelines are available for KS.

OBJECTIVE

To create the first European Academy of Andrology (EAA) guidelines on KS.

METHODS

An expert group of academicians appointed by the EAA generated a consensus guideline according to the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) system.

RESULTS

Clinical features are highly variable among patients with KS, although common characteristics are severely attenuated spermatogenesis and Leydig cell impairment, resulting in azoospermia and hypergonadotropic hypogonadism. In addition, various manifestations of neurocognitive and psychosocial phenotypes have been described as well as an increased prevalence of adverse cardiovascular, metabolic and bone-related conditions which might explain the increased morbidity/mortality in KS. Moreover, compared to the general male population, a higher prevalence of dental, coagulation and autoimmune disorders is likely to exist in patients with KS. Both genetic and epigenetic effects due to the supernumerary X chromosome as well as testosterone deficiency contribute to this pathological pattern. The majority of patients with KS is diagnosed during adulthood, but symptoms can already become obvious during infancy, childhood or adolescence. The paediatric and juvenile patients with KS require specific attention regarding their development and fertility.

CONCLUSION

These guidelines provide recommendations and suggestions to care for patients with KS in various developmental stages ranging from childhood and adolescence to adulthood. This advice is based on recent research data and respective evaluations as well as validations performed by a group of experts.

Why pediatricians need to know the disorders of sex development: experience of 709 cases in a specialized service

OBJECTIVE

To evaluate, in a sample of patients with disorders of sex development (DSD), data related to the age at referral and their correlation with the initial complaints, gender at referral, defined gender after diagnosis and etiological diagnosis.

METHODS

Retrospective review of the age at the first consultation and the reason for it, initial social gender and gender after the diagnosis, karyotype and etiological diagnosis of all cases treated at a DSD outpatient clinic between 1989 and 2016. Cases that did not involve DSD and DSD diagnoses that do not usually involve ambiguous genitalia, thus not requiring specialized monitoring, were excluded.

RESULTS

Of the 1793 treated cases, 1139 were diagnosed with some type of DSD. This study excluded 430 cases (272 with Turner's syndrome, 66 with Klinefelter syndrome, and 92 with pure gonadal dysgenesis), thus a total 709 individuals were included. Of these, 82.9% were referred due to ambiguous genitalia; only one-quarter were still in the first month of life, and 6.6% were referred due to pubertal delay, with most of them aged 10 years or older. Of these patients, 68.6% had a diagnosis of XY DSD, 22.4% of XX DSD, and 9% of sex chromosome abnormalities.

CONCLUSIONS

This study presents the largest series in the literature of patients with DSD treated in a single center. The time of referral of the majority of patients with ambiguous genitalia fell short of the ideal, and milder cases of ambiguous genitalia and many with pubertal manifestations were referred even later. The results reinforce the importance of continuing education for professionals who will have the first contact with these patients, mainly pediatricians and neonatologists.

Early neurodevelopmental and medical profile in children with sex chromosome trisomies: Background for the prospective eXtraordinarY babies study to identify early risk factors and targets for intervention

Sex chromosome trisomies (SCT), including Klinefelter syndrome/XXY, Trisomy X, and XYY syndrome, occur in 1 of every 500 births. The past decades of research have resulted in a broadening of known associated medical comorbidities as well as advances in psychological research. This review summarizes what is known about early neurodevelopmental, behavioral, and medical manifestations in young children with SCT. We focus on recent research and unanswered questions related to the risk for neurodevelopmental disorders that commonly present in the first years of life and discuss the medical and endocrine manifestations of SCT at this young age. The increasing rate of prenatal SCT diagnoses provides the opportunity to address gaps in the existing literature in a new birth cohort, leading to development of the eXtraordinarY Babies Study. This study aims to better describe and compare the natural history of SCT conditions, identify predictors of positive and negative outcomes in SCT, evaluate developmental and autism screening measures commonly used in primary care practices for the SCT population, and build a rich data set linked to a bank of biological samples for future study. Results from this study and ongoing international research efforts will inform evidence-based care and improve health and neurodevelopmental outcomes.

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.

Testosterone Treatment in Infants With 47,XXY: Effects on Body Composition

Context

Boys with XXY have greater adiposity and a higher risk of cardiovascular disease. Infants with XXY have lower testosterone concentrations than typical boys, but no studies have evaluated adiposity in infants with XXY or the physiologic effects of giving testosterone replacement.

Objective

To determine the effect of testosterone on body composition in infants with XXY.

Design

Prospective, randomized trial.

Setting

Tertiary care pediatric referral center.

Participants

20 infants 6 to 15 weeks of age with 47,XXY.

Intervention

Testosterone cypionate 25 mg intramuscularly monthly for three doses vs no treatment.

Main Outcome Measures

Difference in change in adiposity (percent fat mass z scores); other body composition measures, penile length, and safety outcomes between treated and untreated infants; and comparison with typical infants.

Results

The increase in percent fat mass (%FM) z scores was greater in the untreated group than in the treated group (+0.92 ± 0.62 vs −0.12 ± 0.65, P = 0.004). Increases in secondary outcomes were greater in the testosterone-treated group for total mass, fat-free mass, length z score, stretched penile length, and growth velocity (P < 0.002 for all). At 5 months of age, adiposity in untreated infants with XXY was 26.7% compared with 23.2% in healthy male infants of the same age (P = 0.0037); there was no difference in %FM between the treated XXY boys and controls. Reported side effects were minimal and self-limited; no serious adverse events occurred.

Conclusions

Adiposity of untreated infants was 15% greater than that of male controls by 5 months of age. Testosterone treatment for infants with XXY resulted in positive changes in body composition.

A child with Klinefelter syndrome and both IgE-mediated food allergy and low proportion of naive Treg

This case suggests a possible association between Klinefelter Syndrome and decreased regulatory T cells (Treg) cells, relating to an increased risk of allergic and autoimmune disorders in these patients. The immune phenotyping of the circulating FOXP3+ naive Treg populations in KS patients may help to indicate this predisposition.

The Association of Motor Skills and Adaptive Functioning in XXY/Klinefelter and XXYY Syndromes

Aims: Klinefelter (XXY) and XXYY syndromes are genetic disorders in males characterized by additional sex chromosomes compared to the typical male karyotype of 46, XY. Both conditions have been previously associated with motor delays and motor skills deficits. We aimed to describe and compare motor skills in males with XXY and XXYY syndromes, and to analyze associations with age, cognitive abilities, and adaptive functioning. Methods: Sixty-four males with XXY and 46 males with XXYY, ages 4-20 were evaluated using the Beery Test of Visual Motor Integration and the Bruininks-Oseretsky Test of Motor Proficiency - 2nd Edition assessments, Vineland-2 adaptive scales, and cognitive testing. Results: Motor coordination impairments were found in 39% of the males with XXY and 73% of the males with XXYY. Both groups showed strengths in visual perceptual skills. Males with XXYY had lower mean scores compared to males with XXY across all assessments. Fine motor dexterity and coordination deficits were common. There was a positive correlation between VMI scores and adaptive functioning. Conclusion: Occupational and physical therapists should be aware of the motor phenotype in XXY and XXYY both to aid in diagnosis of unidentified cases and to guide intervention.

Population-based trends in the prenatal diagnosis of sex chromosome aneuploidy before and after non-invasive prenatal testing

OBJECTIVE

To assess the impact of non-invasive prenatal testing (NIPT) on trends in the prenatal diagnosis of sex chromosome aneuploidy (SCA) in a population with >73,000 annual births.

METHOD

Retrospective population-based cohort study from 1986-2016 of all women undergoing prenatal diagnosis before 25 weeks gestation in the Australian state of Victoria. Statistical significance was tested using the chi-square test for trend or proportions.

RESULTS

There were 2,043,345 births and 842 SCA diagnoses from 1986-2016. The percentage of prenatal diagnostic tests leading to a SCA diagnosis increased significantly from 0.95% in 2010 to 2.93% in 2016 (p < 0.001) but due to a concurrent decline in testing, the annual prenatal diagnosis rate of SCA remained stable at 4.4/10,000 births. Among confirmed fetal SCAs the most common indication for testing in 1986 was advanced maternal age (63%); in 2016 it was high risk NIPT (49%).

CONCLUSION

SCAs now make up an increasing proportion of prenatal diagnostic results but due to the overall decline in diagnostic testing, the prenatal prevalence as a percentage of births remained steady. The ascertainment of fetal SCA has evolved from an incidental finding after testing for increased risk of trisomy 21, to a diagnosis obtained after suspected SCA on NIPT.

Klinefelter syndrome: a speech-language and neuropsychological assessment

ABSTRACT The Klinefelter syndrome is a chromosomal aneuploidy caused by additional X chromosomes in men. The diagnosis is made by clinical observation and karyotype examination. Besides other characteristics, the phenotype involves infertility, hypogonadism, gynecomastia, and cognitive alterations, mainly in the language domain. This paper describes the case of a teenager with Klinefelter syndrome and history of difficulties in the learning process, behavioral and communication problems. The ethical guidelines were followed in the present report. The cognitive-communicative, pragmatic and syntactic profile was drawn from the speech and neuropsychological evaluations. The speech-language assessment showed deficits in expression and comprehension. Difficulties were also found in phonological awareness, mathematical operations, reading and writing, access to the lexicon, alterations in pragmatics and occasionally, in syntactics. The neuropsychological evaluation indicated impairments in tasks that require the identification of similarities, establishment of cause-effect relationships and analogies, demonstrating a compromised reasoning for logical operations, with intellectual level incompatible with the chronological age. This interdisciplinary clinical study favors intervention approaches in rehabilitation, to maximize the potential of the individuals affected, contributing to improve their quality of life.

Oxandrolone Treatment Results in an Increased Risk of Gonadarche in Prepubertal Boys With Klinefelter Syndrome

CONTEXT

Klinefelter syndrome (KS) is a common genetic condition in which males have an extra X chromosome. KS is associated with testosterone deficiency, neurodevelopmental delays, and cardiometabolic disorders. There has been recent interest in prepubertal androgen treatment; however, the effects on puberty and gonadal function are unknown.

OBJECTIVE

To compare onset of puberty and testicular function in prepubertal boys treated with 2 years of oxandrolone (Ox) vs placebo (Pl).

DESIGN

Double-blind, randomized, controlled trial.

SETTING

Single tertiary care referral center.

PARTICIPANTS

Eighty prepubertal boys with KS; mean age: 8.0 ± 2.2 years (range: 4 to 12).

INTERVENTIONS

Ox 0.05 mg/kg vs identical-appearing Pl capsule given for 2 years.

OUTCOME MEASURES

Onset of gonadarche (testicular volume ≥4 mL) and onset of pubarche (Tanner 2 pubic hair); change in testicular hormone concentrations.

RESULTS

Ox-treated group had 20.5 times higher odds of reaching gonadarche (OR 95% CI: 6.5, 77.8) and 28.1 times higher odds of reaching pubarche (OR 95% CI: 8.8, 110.4) during the 2-year study period after adjusting for baseline age. Gonadarche and pubarche both occurred at a younger age in the Ox group (gonadarche: 9.8 ± 1.5 vs 12.1 ± 1.0 years, P < 0.001; pubarche: 10.2 ± 1.1 vs 11.6 ± 1.3 years, P = 0.02). Serum concentrations of testicular hormones and gonadotropins were not different between groups.

CONCLUSIONS

Two years of Ox treatment in prepubertal boys with KS results in an increased risk of early gonadarche, on average 2 years earlier than in Pl-treated boys. Ox did not affect serum concentrations of testicular hormones.

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.

Klinefelter syndrome, insulin resistance, metabolic syndrome, and diabetes: review of literature and clinical perspectives

PURPOSE

Klinefelter syndrome (KS), the most frequent chromosomic abnormality in males, is associated with hypergonadotropic hypogonadism and an increased risk of cardiovascular diseases (CVD). The mechanisms involved in increasing risk of cardiovascular morbidity and mortality are not completely understood. This review summarises the current understandings of the complex relationship between KS, metabolic syndrome and cardiovascular risk in order to plan future studies and improve current strategies to reduce mortality in this high-risk population.

METHODS

We searched PubMed, Web of Science, and Scopus for manuscripts published prior to November 2017 using key words "Klinefelter syndrome" AND "insulin resistance" OR "metabolic syndrome" OR "diabetes mellitus" OR "cardiovascular disease" OR "testosterone". Manuscripts were collated, studied and carried forward for discussion where appropriate.

RESULTS

Insulin resistance, metabolic syndrome, and type 2 diabetes are more frequently diagnosed in KS than in the general population; however, the contribution of hypogonadism to metabolic derangement is highly controversial. Whether this dangerous combination of risk factors fully explains the CVD burden of KS patients remains unclear. In addition, testosterone replacement therapy only exerts a marginal action on the CVD system.

CONCLUSION

Since fat accumulation and distribution seem to play a relevant role in triggering metabolic abnormalities, an early diagnosis and a tailored intervention strategy with drugs aimed at targeting excessive visceral fat deposition appear necessary in patients with KS.

Klinefelter Syndrome in Childhood: Variability in Clinical and Molecular Findings

OBJECTIVE

Klinefelter syndrome (KS) is the most common (1/500–1/1000) chromosomal disorder in males, but only 10% of cases are identified in childhood. This study aimed to review the data of children with KS to assess the age and presenting symptoms for diagnosis, clinical and laboratory findings, together with the presence of comorbidities.

METHODS

Twenty-three KS patients were analyzed retrospectively. Age at admission, presenting symptoms, comorbid problems, height, weight, pubertal status, biochemical findings, hormone profiles, bone mineral density and karyotype were evaluated. Molecular analysis was also conducted in patients with ambiguous genitalia.

RESULTS

The median age of patients at presentation was 3.0 (0.04-16.3) years. Most of the cases were diagnosed prenatally (n=15, 65.2%). Other reasons for admission were scrotal hypospadias (n=3, 14.3%), undescended testis (n=2, 9.5%), short stature (n=1, 4.8%), isolated micropenis (n=1, 4.8%) and a speech disorder (n=1, 4.8%). The most frequent clinical findings were neurocognitive disorders, speech impairment, social and behavioral problems and undescended testes. All except two patients were prepubertal at admission. Most of the patients (n=20, 86.9%) showed the classic 47,XXY karyotype. Steroid 5 alpha-reductase 2 gene and androgen receptor gene mutations were detected in two of the three cases with genital ambiguity.

CONCLUSION

Given the large number of underdiagnosed KS patients before adolescence, pediatricians need to be aware of the phenotypic variability of KS in childhood. Genetic analysis in KS patients may reveal mutations associated with other forms of disorders of sex development besides KS.

Disorders of sex development

Normal sex development depends on the precise spatio-temporal sequence and coordination of mutually antagonistic activating and repressing factors. These factors regulate the commitment of the unipotential gonad into the binary pathways governing normal sex development. Typically, the presence of the SRY gene on the Y chromosome triggers the cascade of molecular events that lead to male sex development. Disorders of sex development comprise a heterogeneous group of congenital conditions associated with atypical development of internal and external genitalia. These disorders are generally attributed to deviations from the typical progression of sex development. Disorders of sex development can be classified into several categories including chromosomal, gonadal, and anatomic abnormalities. Genetic tools such as microarray analyses and next-generation sequencing techniques have identified novel genetic variants among patients with disorders of sexual development. Most importantly, patient management needs to be individualized, especially for decisions related to sex of rearing, surgical interventions, hormone treatment, and potential for fertility preservation.

Sex chromosome aneuploidies

Sex chromosome aneuploidies comprise a relatively common group of chromosome disorders characterized by the loss or gain of one or more sex chromosomes. We discuss five of the better-known sex aneuploidies: Turner syndrome (XO), Klinefelter syndrome (XXY), trisomy X (XXX), XYY, and XXYY. Despite their prevalence in the general population, these disorders are underdiagnosed and the specific genetic mechanisms underlying their phenotypes are poorly understood. Although there is considerable variation between them in terms of associated functional impairment, each disorder has a characteristic physical, cognitive, and neurologic profile. The most common cause of sex chromosome aneuploidies is nondisjunction, which can occur during meiosis or during the early stages of postzygotic development. The loss or gain of genetic material can affect all daughter cells or it may be partial, leading to tissue mosaicism. In both typical and atypical sex chromosome karyotypes, there is random inactivation of all but one X chromosome. The mechanisms by which a phenotype results from sex chromosome aneuploidies are twofold: dosage imbalance arising from a small number of genes that escape inactivation, and their endocrinologic consequences.

Genetic testing including targeted gene panel in a diverse clinical population of children with autism spectrum disorder: Findings and implications

BACKGROUND

Genetic testing of children with autism spectrum disorder (ASD) is now standard in the clinical setting, with American College of Medical Genetics and Genomics (ACMGG) guidelines recommending microarray for all children, fragile X testing for boys and additional gene sequencing, including PTEN and MECP2, in appropriate patients. Increasingly, testing utilizing high throughput sequencing, including gene panels and whole exome sequencing, are offered as well.

METHODS

We performed genetic testing including microarray, fragile X testing and targeted gene panel, consistently sequencing 161 genes associated with ASD risk, in a clinical population of 100 well characterized children with ASD. Frequency of rare variants identified in individual genes was compared with that reported in the Exome Aggregation Consortium (ExAC) database.

RESULTS

We did not diagnose any conditions with complete penetrance for ASD; however, copy number variants believed to contribute to ASD risk were identified in 12%. Eleven children were found to have likely pathogenic variants on gene panel, yet, after careful analysis, none was considered likely causative of disease. KIRREL3 variants were identified in 6.7% of children compared to 2% in ExAC, suggesting a potential role for KIRREL3 variants in ASD risk. Children with KIRREL3 variants more often had minor facial dysmorphism and intellectual disability. We also observed an increase in rare variants in TSC2. However, analysis of variant data from the Simons Simplex Collection indicated that rare variants in TSC2 occur more commonly in specific racial/ethnic groups, which are more prevalent in our population than in the ExAC database.

CONCLUSION

The yield of genetic testing including microarray, fragile X (boys) and targeted gene panel was 12%. Gene panel did not increase diagnostic yield; however, we found an increase in rare variants in KIRREL3. Our findings reinforce the need for racial/ethnic diversity in large-scale genomic databases used to identify variants that contribute to disease risk.

Androgen Treatment Effects on Motor Function, Cognition, and Behavior in Boys with Klinefelter Syndrome

OBJECTIVES

To examine the effects of early low-dose androgen on motor, cognitive, and behavioral function in prepubertal boys with Klinefelter syndrome (47,XXY).

STUDY DESIGN

Double-blind trial of 84 boys, ages 4-12 years, randomized to oxandrolone (Ox; 0.06?mg/kg daily; n?=?43) or placebo (Pl; n?=?41) for 24 months. Standardized assessments were performed at baseline and every 12 months for 24 months evaluating motor, cognitive, and behavioral function.

RESULTS

The 24-month outcomes were better in the Ox vs. Pl group on 1 of 5 primary endpoints (motor function/strength): Bruininks Visual-Motor scale (P?=?.005), without significant differences between the 2 groups for the other 4 components. Secondary analyses suggested improvement in the Ox vs. Pl group in the anxiety/depression (P?=?.03) and social problems (P?=?.01) scales on the Child Behavior Checklist, anxiety (P?=?.04) on the Piers Harris Self Concept Scale, and interpersonal problems (P?=?.02) on the Children's Depression Inventory, without significant differences in hyperactive or aggressive behaviors.

CONCLUSIONS

This double-blind, randomized trial demonstrates that 24 months of childhood low-dose androgen treatment in boys with Klinefelter syndrome benefited 1 of 5 primary endpoints (visual-motor function). Secondary analyses demonstrated positive effects of androgen on aspects of psychosocial function (anxiety, depression, social problems), without significant effects on cognitive function, or hyperactive or aggressive behaviors.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00348946.

Effects of Oxandrolone on Cardiometabolic Health in Boys With Klinefelter Syndrome: A Randomized Controlled Trial

CONTEXT

Klinefelter syndrome (KS) is a common condition in males, resulting in androgen deficiency and cardiometabolic diseases. These interrelated conditions may be present in prepubertal boys with KS.

OBJECTIVE

To determine whether supplemental low-dose androgen has a beneficial effect on body composition in prepubertal boys with KS.

DESIGN, SETTING, AND PARTICIPANTS

We conducted a secondary analysis of a randomized, double-blind, placebo-controlled clinical trial in 93 boys with KS aged 4 to 12 years.

INTERVENTIONS

Oral oxandrolone (Ox) 0.06 mg/kg/d or placebo for 2 years.

OUTCOME MEASURES

The primary outcome was percent body fat standard deviation score (%BF SDS) at 2 years. Secondary outcomes included additional measures of cardiometabolic health and safety.

RESULTS

The %BF SDS at 2 years was significantly lower in the treatment (0.29 ± 0.76 SDS) compared with placebo group (0.81 ± 0.72 SDS) after adjusting for age and baseline %BF SDS (95% confidence interval for the difference between means -0.86 to -0.19 SDS, P = 0.009). Ox resulted in lower triglycerides (P = 0.043), but also lower high-density lipoprotein (HDL) cholesterol (P < 0.001) and a more rapid advancement in bone age (P = 0.011).

CONCLUSIONS

Ox has positive effects on measures of cardiometabolic health in prepubertal boys with KS; however, it does lower HDL cholesterol and advance bone age.