A small blood sample is sufficient as test material. In the past, the observation of the Barr body was common practice, as well. To investigate the presence of a possible mosaicism, analysis of the karyotype using cells from the oral mucosa is performed. Physical characteristics of a Klinefelter syndrome can be tall stature, low body hair, and occasionally an enlargement of the breast. Usually, a small testicle volume of 1–5 ml per testicle (standard values: 12–30 ml) occurs. During puberty and adulthood, low testosterone levels with increased levels of the pituitary hormones FSH and LH in the blood can indicate the presence of Klinefelter syndrome. A spermiogram can also be part of the further investigation. Often. an azoospermia is present, or rarely an oligospermia. Furthermore, Klinefelter syndrome can be diagnosed as a coincidental prenatal finding in the context of invasive prenatal diagnosis (amniocentesis, chorionic villus sampling). About 10% of KS cases are found by prenatal diagnosis.The symptoms of KS are often variable, so a karyotype analysis should be ordered when small testes, infertility, gynecomastia, long arms/legs, developmental delay, speech/language deficits, learning disabilities/academic issues, and/or behavioral issues are present in an individual. Treatment
As the genetic variation is irreversible, no causal therapy is available. From the onset of puberty, the existing testosterone deficiency can be compensated by appropriate hormone-replacement therapy. Testosterone preparations are available in the form of syringes, patches, or gel.
If gynecomastia is present, the surgical removal of the breast may be considered for both the psychological reasons and to reduce the risk of breast cancer.The use of behavioral therapy can mitigate any language disorders, difficulties at school, and socialization. An approach by occupational therapy is useful in children, especially those who have dyspraxia. Infertility treatment
Methods of reproductive medicine, such as intracytoplasmic sperm injection (ICSI) with previously conducted testicular sperm extraction (TESE), have led to men with Klinefelter syndrome producing biological offspring. By 2010, over 100 successful pregnancies have been reported using IVF technology with surgically removed sperm material from males with KS. Prognosis
The lifespan of individuals with Klinefelter syndrome appears to be reduced by around 2.1 years compared to the general male population. These results are still questioned data, are not absolute, and need further testing. Epidemiology
This syndrome, evenly distributed in all ethnic groups, has a prevalence of approximately four subjects per every 10,000 (0.04%) males in the general population. However, it is estimated that only 25% of the individuals with Klinefelter syndrome are diagnosed throughout their lives. The rate of Klinefelter syndrome among infertile males is 3.1%. The syndrome is also the main cause of male hypogonadism. History
The syndrome was named after American endocrinologist Harry Klinefelter, who in 1942 worked with Fuller Albright and E. C. Reifenstein at Massachusetts General Hospital in Boston, Massachusetts, and first described it in the same year.