On the upside, we did find that those men with KS receiving testosterone treatment were on average born and diagnosed more recently compared with the untreated group, which could indicate an improving standard of care over the last years (Chang, Christiansen, et al., 2019) (Figure 1). In total, six studies (Close et al., 2015; de Ronde et al., 2009; Fjermestad & Stokke, 2018; Herlihy, McLachlan, et al., 2011; Skakkebaek et al., 2018; Turriff et al., 2015) have compared quality of life or aspects of quality of life of KS patients with existing data from a population normative data, a male reference group, a male control group, or without a comparison group (Table 1). The greatest challenge faced by adolescents and adults with KS were infertility and psychological comorbidity, in addition to learning disabilities, physical phenotype, social relationships, employment problems, challenges with health care providers, and testosterone treatment challenges (Turriff, Macnamara, Levy, & Biesecker, 2017). If an egg cell with an extra X chromosome (XX) is fertilized by a sperm cell with one Y chromosome, the resulting child will have Klinefelter syndrome. However, because of nondisjunction, an egg cell or a sperm cell can also end up with an extra copy of the X chromosome. Typically, as cells divide, each egg cell gets a single X chromosome, and each sperm cell gets either an X chromosome or a Y chromosome. During cell division, an error called nondisjunction prevents X chromosomes from being distributed normally among reproductive cells as they form. Klinefelter syndrome is not inherited; the addition of an extra X chromosome occurs during the formation of reproductive cells (eggs or sperm) in one of an affected person's parents. Additional strengths of our findings include the large sample size and the ability to establish the chronology of diagnosis and further evaluation and management. Despite the recommendation to provide TRT to hypogonadal men with KS, there is a paucity of data describing real-world prescription of TRT in these men. Patients who received T measurement and subsequent treatment. In total, of these 5347 patients, 1484 (27.8%) were prescribed any form of TRT (Table 1). Data on comorbidities, including mental retardation (F70-F79), type 2 diabetes mellitus (E11), obesity (E66), hyperlipidemia (E78.5), hypertension (I10), osteoporosis (M81), pulmonary embolism (I26), and other vascular thrombosis (I74), were collected for all patients in addition to demographic characteristics. In this large retrospective study, TRT was underprescribed in men with KS. This is the first study to evaluate TRT prescribing habits in men with KS. The extra chromosome is retained because of a nondisjunction event during paternal meiosis I, maternal meiosis I, or maternal meiosis II, also known as gametogenesis. Women at 40 years have a four-times-higher risk of a child with Klinefelter syndrome than women aged 24 years. The extra X chromosome comes from the mother in approximately 50% of the cases. While testosterone replacement therapy is very successful for some people, it doesn’t work for everybody. These treatments are particularly important if you have Klinefelter syndrome, a genetic condition that affects your body’s ability to produce testosterone. As more adolescent and young adult (AYA) patients with KS seek care, it becomes increasingly important to investigate their understanding of information about testosterone supplementation and infertility. The results do not support universal adoption of testosterone treatment into current clinical practice for infants with XXY. Individuals with Klinefelter syndrome typically have small testes that produce a reduced amount of testosterone (primary testicular insufficiency). Unauthorized use of these marks is strictly prohibited. The strongest associations were with body fat, indicating that metabolic dysfunction may be a key regulator of contact activation system activity. Contact activation system mediates crosstalk between coagulation, fibrinolysis, and inflammation and may contribute to thromboinflammatory risk. While hypogonadism and metabolic dysfunction are known contributors, the role of the contact activation system in Klinefelter syndrome remains unexplored.
