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Klinefelter syndrome in clinical practice.
Anders Bojesen1, Claus H Gravholt
1Department of Clinical Genetics, Vejle Hospital, Aarhus University Hospital, Denmark. anders.bojesen@dadlnet.dk
Nature Clinical Practice. Urology
|April 7, 2007
Summary
Klinefelter syndrome, a common sex-chromosome disorder affecting 1 in 660 men, is often underdiagnosed. Early diagnosis and lifelong testosterone therapy are crucial for managing hypogonadism and ensuring proper development.
Area of Science:
- Genetics
- Endocrinology
- Reproductive Health
Background:
- Klinefelter syndrome (KS) is the most frequent sex-chromosome abnormality in males, affecting approximately 1 in 660 individuals.
- The condition is characterized by the presence of extra X chromosomes, with 47,XXY being the most common karyotype.
- The typical phenotype includes tall stature, gynecomastia, small testes, and androgen deficiency, though presentations can vary.
Purpose of the Study:
- To summarize the key characteristics, diagnostic challenges, and management principles of Klinefelter syndrome.
- To highlight the underdiagnosis rate and the importance of timely intervention.
- To underscore the necessity of testosterone supplementation for long-term health outcomes.
Main Methods:
- Review of existing literature on Klinefelter syndrome.
- Analysis of epidemiological data regarding prevalence and diagnosis rates.
- Synthesis of current clinical guidelines for testosterone replacement therapy.
Main Results:
- Klinefelter syndrome is significantly underdiagnosed, with only 25% of expected cases identified.
- A majority of diagnoses occur after puberty, delaying essential treatment.
- Lifelong testosterone supplementation initiated at puberty is recommended for managing hypogonadism.
Conclusions:
- Early diagnosis and consistent testosterone therapy are vital for individuals with Klinefelter syndrome.
- Optimal testosterone regimens require further investigation to maximize benefits.
- Addressing the underdiagnosis of KS is critical for improving patient outcomes and preventing long-term complications.
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