Follow-up of 30 Klinefelter males treated with testosterone

Thirty Klinefelter males treated with testosterone were studied by a follow-up examination carried out an average of 3.6 years after treatment began. The age of the men averaged 25.5 years at the time of the follow-up. Seventy-seven per cent of the men were judged to have benefited from testosterone treatment. They showed better mood, less irritability, more energy and drive, less tiredness, more endurance and strength, less need for sleep, better concentration ability and better relations with others during testosterone treatment. The beneficial effects of testosterone persisted in some of the men after cessation of treatment. The findings show that Klinefelter males given testosterone for the first time as adults can benefit from such treatment, even though it is preferable to start treatment at the age of 11-12 years.     

Gonadal dysfunction and beyond: Clinical challenges in children,adolescents, and adults with 47,XXY Klinefelter syndrome

Klinefelter syndrome (KS) is the most frequent sex chromosomal aneuploidy. The karyotype 47,XXY originates from either paternal or maternal meiotic nondisjunction during gametogenesis. KS males are very likely to exhibit marked gonadal dysfunctions, presenting both in severely attenuated spermatogenesis as well as hypergonadotropic hypogonadism. In addition, neurocognitive and psychosocial impairments, as well as cardiovascular, metabolic and bone disorders are often found in KS and might explain for an increased morbidity/mortality. All conditions in KS are likely to be induced by both gene overdosage effects resulting from supernumerary X‐chromosomal genes as well as testosterone deficiency. Notwithstanding, the clinical features are highly variable between KS men. Symptoms can become obvious at infancy, childhood, or adolescence. However, the majority of KS subjects is diagnosed during adulthood. KS adolescents require specific attention regarding pubertal development, in order to exploit their remaining fertility potential and allow for timely and tailored testosterone replacement. The chances for sperm retrieval might decline with age and could be hampered by testosterone replacement; therefore, cryostorage of spermatozoa is an option during adolescence, before the decompensation of endocrine and exocrine testicular functions becomes more overt. Sperm from semen or surgically retrieved, in combination with intracytoplasmic sperm injection enables KS males to become biological fathers of healthy children. The aim of this article is to present the current knowledge on KS, to guide clinical care and to highlight research needs.     

Screening for fra(x) mutation and Klinefelter syndrome in mental institutions

A total of 9153 male subjects in mental institutions from six different Italian districts were screened for the presence of bilateral microorchidism, in order to detect Klinefelter syndrome. Among the 212 microorchidic patients found, 33 had an XXY karyotype (15.5%). Ninety-one Klinefelter patients with normal intelligence were also examined as a control group. Cytogenetical and clinical findings were compared in these two groups of patients and no difference was found. Two fra(x)positive subjects were found, one for each group of XXY patients; the influence of fra(x) mutation on their phenotype is discussed.     

Endocrinological issues and hormonal manipulation in children and men with Klinefelter syndrome

47, XXY or Klinefelter syndrome (KS), the most common chromosomal aberration in males, is characterized by either absolute or relative hypogonadism with frequent decline in serum testosterone (T) following the onset of puberty. Decreased T levels are the result of testicular dysfunction with decrease in size of Leydig cells, and loss of germs and Sertoli cells leading to tubular hyalinization. Increase in estradiol results from over-expression of aromatase CYP19. Deficient androgen production and observed varied response of end-organs to T leads to delayed progression of puberty with decreased facial/body hair, poor muscle development, osteoporosis, and gynecomastia. It is possible that hypogonadism and excessive estradiol production contribute to emotional and social immaturity, and specific learning disabilities in KS. Based on the authors' experience and literature review, early fertility preservation and hormonal supplementation may normalize pubertal development, prevent metabolic sequelae of hypogonadism, and have a positive effect on academic and social development. No randomized clinical trials are available studying the effects of T supplementation on reproductive or cognitive issues in KS. Aggressive T supplementation (topical gel) and selective use of aromatase inhibitors may be considered at the onset of puberty with careful follow-up and titration to reach age-specific high-normal physiologic serum values. The decision to institute hormonal therapy should be part of a multidisciplinary approach including physical, speech, behavioral, and occupational therapy. © 2013 Wiley Periodicals, Inc.     

47,XXY Klinefelter syndrome: Clinical characteristics and age-specific recommendations for medical management

47,XXY (Klinefelter syndrome) is the most frequent sex chromosomal disorder and affects approximately one in 660 newborn boys. The syndrome is characterized by varying degrees of cognitive, social, behavioral, and learning difficulties and in adulthood additionally primary testicular failure with small testes, hypergonadotropic hypogonadism, tall stature, and eunuchoid body proportions. The phenotype is variable ranging from “near-normal” to a significantly affected individual. In addition, newborns with Klinefelter syndrome generally present with a normal male phenotype and the only consistent clinical finding in KS is small testes, that are most often not identified until after puberty. Decreased awareness of this syndrome among health professionals and a general perception that all patients with 47,XXY exhibit the classic textbook phenotype results in a highly under-diagnosed condition with up to 75% of the patients left undetected. Typically, diagnosis is delayed with the majority of patients identified during fertility workup in adulthood, and only 10% of patients diagnosed prior to puberty. Early detection of this syndrome is recommended in order to offer treatment and intervention at the appropriate ages and stages of development for the purpose of preventing osteopenia/osteoporosis, metabolic syndrome, and other medical conditions related to hypogonadism and to the XXY as well as minimizing potential learning and psychosocial problems. The aim of this review is to present the clinical aspects of XXY and the age-specific recommendations for medical management. © 2013 Wiley Periodicals, Inc.     

Klinefelter综合征研究的新进展

不孕不育是影响人类生殖健康的重要问题。估计在男性不育症患者中染色体异常占2%-8%,平均5%。其中最为常见的染色体异常就是克氏综合征。过去大多数人认为克氏综合征患者是不育的,没有作父亲的可能,然而随着近年来辅助生殖技术的发展,已有克氏综合征患者通过辅助生殖技术生出健康后代的报到。本文就目前克氏综合征的一些新进展作一综述。     

克氏综合征基因表达谱分析

目的 对克氏综合征（Klinefelter syndrome）患者进行基因表达谱分析,探讨其基因差异表达与临床表型之间的关系.方法 采用第二代高通量测序方法对7例克氏综合征患者和7例对照男性外周血全基因组mRNA进行深度测序,运用定量RT-PCR方法对30例克氏综合征患者及30例对照男性进行验证.结果 测序结果根据FDR≤0.001和｜ log2 Ratio≥1 ｜的标准,两组比较存在差异表达基因216个,差异具有统计学意义.其中X染色体基因9个,占4％,与X染色体失活相关的XIST差异表达最明显;常染色体基因207个,占96％,其中NR4A3、ZKSCAN4、HBEGF、EREG、AREG、NR4A2、CCR5差异表达明显.NR4A3主要.与2型糖尿病有关,HBEGF主要参与促性腺激素分泌过程.Y染色体不存在显著差异表达基因.结论 克氏综合征患者不仅多余X染色体基因差异表达,还有大量常染色体基因差异表达,这可能是克氏综合征临床表型多样化的原因.     

Effect of Testosterone Replacement Therapy on Bone Mineral Density in Patients with Klinefelter Syndrome

Purpose

Klinefelter syndrome (KS) is related to testicular insufficiency, which causes low testosterone levels in serum. Generally, sex hormone levels and bone mineral density (BMD) are lower in patients with KS than normal. We investigated the effects of testosterone replacement on serum testosterone levels and BMD in KS patients.

Materials and Methods

From December 2005 to March 2008, 18 KS patients with a 47, XXY karyotype were treated with initial intramuscular injections of long-acting testosterone undecanoate (Nebido®, 1000 mg/4 mL) at baseline and second injections after six weeks. An additional four injections were administered at intervals of 12 weeks after the second injection. BMD was measured at the lumbar spine (L2-4), the left femoral neck and Ward''s triangle, using dual energy X-ray absorptiometry. Medical histories, physical examinations and prostate specific antigen, hematology and serum chemistry were conducted for each patient. In addition, total testosterone and sex hormone-binding globulin levels were measured.

Results

Following testosterone replacement, mean serum total testosterone increased significantly from baseline (0.90 vs. 4.51 ng/mL, p<0.001), and total testosterone rose to normal levels after replacement in all patients. The mean BMD of the lumbar spine increased significantly (0.91 vs. 0.97 g/cm², p<0.001). Similar increases of BMD were also observed at the femoral neck, but this increase was not significant.

Conclusion

These findings suggest that testosterone replacement therapy may be effective in treating BMD deficiency in men with testosterone deficiency, especially those with Klinefelter syndrome.     

Klinefelter综合征的早期诊断(附14例报告)

本文总结了14例克氏综合征，最小2岁，最大38岁，表现型为男性，但阴茎短小，睾丸小，性成熟期不能产生精子，细胞核型以47，XXY为最多，占80％，嵌合型占10％，罕见核型占10％。产生机制是经细胞分裂过程中发生性染色体不分离所致，其原因有待进一步探索。口腔粘膜X染色质检查对早期诊断克氏综合征具有重要意义，强调对男性新生儿本病普查的必要性。     

Metabolic and cardiovascular risk factors in Klinefelter syndrome

Klinefelter syndrome (KS), which normally presents with a 47,XXY karyotype, is the most common sex chromosome disorder in males. It is also the most common genetic cause of male infertility. KS subjects are typically tall, with small and firm testes, gynecomastia, broad hips, and sparse body hair, although a less evident presentation is also possible. KS is also characterized by a high prevalence of hypogonadism, metabolic syndrome (MetS) and cardiovascular disease. The aim of this article is to systematically review metabolic and the cardiovascular risk factors in KS patients. Hypogonadism has an important role in the pathogenesis of the changes in body composition (particularly visceral obesity) and hence of insulin resistance and MetS, but the association between KS and MetS may go beyond hypogonadism alone. From childhood, KS patients may show an increase in visceral fat with a reduction in lean body mass and an increase in glucose and impaired fat metabolism. Their increased incidence of congenital anomalies, epicardial adipose tissue, and thromboembolic disease suggests they have a higher risk of cardiovascular disease. There is conflicting evidence on the effects of testosterone therapy on body composition and metabolism.     

Association of the X chromosomal region q11→22 and Klinefelter syndrome

A male patient with typical Klinefelter syndrome features was found to have a 47, XXq-Y chromosome complement. The X chromosome with the deletion was late-replicating. We suggest that the region q11→22 of the extra X chromosome is important for expression of the Klinefelter phenotype.     

Association between the degree of mosaicism and the severity of syndrome in Turner mosaics and Klinefelter mosaics

This study, based on the investigations carried on 82 cases of Turners of which 50 of them were mosaics and 85 cases of Klinefelters of which 70 of them were mosaics, is an attempt to explain the vast range of clinical variations observed in cytogenetically established Turner mosaics (45, X/46, XX) and Klinefelter mosaics (47, XXY/46, XY) in the light of the degree of mosaicism present in them. It was observed that the severity of the syndrome in Turner mosaics and Klinefelter mosaics increased with the relative increase in the abnormal cell line population.     

Short stature in a patient with Klinefelter syndrome and growth hormone deficiency

We report on a child with Klinefelter syndrome and short stature due to idiopathic growth hormone deficiency (IGHD). His height was below the mid-parental height, with a significant delay in bone age. Height velocity increased from 4.5 to 8.2 cm/year during 1 year of GH therapy and typical catch-up growth was observed. No adverse reactions to the treatment were observed. We wish to emphasize the rare association between Klinefelter syndrome and IGHD and the apparent effectiveness and safety of recombinant somatotropin treatment in aneuploid patients. © 1994 Wiley-Liss, Inc.     

Isochromosome Xq in Klinefelter syndrome: Report of 7 new cases

In this collaborative study we report on 2 prenatally and 5 postnatally diagnosed cases with a 47,X,i(Xq), Y chromosomal constitution. Excepting tall stature, the 5 adult patients showed all typical manifestations of Klinefelter syndrome. Taken together with previously reported cases, these data suggest that Klinefelter syndrome with isochromosome Xq has a favorable prognosis with normal mental development, and with normal-to-short stature. The prevalence of this Klinefelter variant is calculated to be between 0.3–0.9% in males with X chromosome polysomies. © 1996 Wiley-Liss, Inc.     

The pituitary in klinefelter syndrome

Background: Klinefelter syndrome is a genetically determined primary gonadal defect characterized by the XXY karyotype. The testes are small, blood testosterone levels are low, and blood gonadotropin levels are elevated. Pituitary changes in patients with Klinefelter syndrome have not been evaluated in detail. Design: The first patient, a 76-yr-old man, was operated for a large sellar mass. The second and third patients, a 62- and a 52-yr-old man, respectively, died of cardiac failure. Both the latter pituitaries were normal-sized and removed at autopsy. The diagnosis of Klinefelter syndrome was confirmed by genetic testing in all three cases. The formalinfixed and paraffin-embedded pituitaries of three patients were evaluated for adenohypophysial hormone immunoreactivity. For immunohistochemistry, the streptavidin-biotin-peroxidase (ABC) complex method was applied. Results: In case 1, histology and immunohistochemistry revealed an oncocytic gonadotroph macroadenoma immunoreactive for FSH and alpha subunit. No pituitary gland was evident. The pituitary of case 2 featured hyperplasia of gonadotrophs, some with features of “gonadal deficiency cells,” and a microadenoma immunoreactive for GH. The pituitary of case 3 similarly showed hyperplasia of gonadotrophs and the formation of gonadal deficiency cells. Conclusion: Protracted stimulation of gonadotrophs due to lack of androgen feedback might have been a factor in the formation of the gonadotroph adenoma in case 1 and in the development of gonadotroph hyperplasia in cases 2 and 3. The clinically silent GH microadenoma of case 2 was regarded as an incidental finding.     

Sperm aneuploidy in fathers of children with paternally and maternally inherited Klinefelter syndrome

BACKGROUND: It is unclear whether frequency of sperm aneuploidy is associated with risk of fathering children with trisomy. METHODS: We recruited 36 families with a boy with Klinefelter syndrome (KS), interviewed the fathers about their exposures and medical history, received a semen sample from each father, and collected blood samples from the mother, father and child. We applied a multicolour fluorescent in-situ hybridization assay to compare the frequencies of sperm carrying XY aneuploidy and disomies X, Y and 21 in fathers of maternally and paternally inherited KS cases. RESULTS: Inheritance of the extra X chromosome was paternal in 10 and maternal in 26 families. Fathers of paternal KS cases produced higher frequencies of XY sperm (P = 0.02) than fathers of maternal KS cases. After controlling for age, the major confounding variable, the difference between the two groups was no longer significant (P less-than-or-equal 0.2). Also, there were no significant differences between the parental origin groups for disomy X, Y or 21. CONCLUSIONS: Men who fathered a child with a Klinefelter syndrome produced higher frequencies of XY sperm aneuploidy, which is explained, in part, by both paternal age and parent of origin.     

Pseudomembranous trigonitis in a male with Klinefelter syndrome: a case report and evidence of a hormonal etiology

Klinefelter syndrome is a clinical syndrome with a distinct 47, XXY karyotype. Patients are characterized by a tall eunuchoid stature, small testes, hypergonotrophic hypogonadism, gynecomastia, learning difficulties and infertility. These patients have also been found to have raised estrogen levels. We report a 16 year old boy with Klinefelter syndrome presenting to our institution with gross hematuria. Cystoscopy and biopsy revealed the diagnosis of pseudomembranous trigonitis. Immunohistochemical stains showed an increase in estrogen and progesterone receptors in the trigone area but not in the rest of the bladder. In view of the patient’s mildly raised estrogen levels and the histological findings, we postulate that estrogen is the driver of the development of pseudomembranous trigonitis. This is the first reported case of pseudomembranous trigonitis seen in association with Klinefelter syndrome, and also the first case of pseudomembranous trigonitis occurring within the male adolescent age group.     

Psychological functioning,brain morphology,and functional neuroimaging in Klinefelter syndrome

Klinefelter syndrome (KS; 47,XXY) impacts neurodevelopment and is associated with an increased risk of cognitive, psychological and social impairments, although significant heterogeneity in the neurodevelopmental profile is seen. KS is characterized by a specific cognitive profile with predominantly verbal deficits, preserved function in non‐verbal and visuo‐spatial domains, executive dysfunction and social impairments, and by an increased vulnerability toward psychiatric disorders. The neurobiological underpinnings of the observed neuropsychological profile have not been established. A distinct pattern of both global and regional brain volumetric differences has been demonstrated in addition to preliminary findings of functional brain alterations related to auditory, motor, language and social processing. When present, the combination of cognitive, psychological and social challenges has the potential to negatively affect quality of life. This review intends to provide information and insight to the neuropsychological outcome and brain correlates of KS. Possible clinical intervention and future directions of research will be discussed.