Klinefelters Syndrome:
Definition
A chromosome abnormality that affects only men and causes hypogonadism.
Causes, Incidence and Risk Factors
Klinefelter's syndrome is caused by an extra X chromosome and affects only males. An infant appears normal at birth, but the defect usually becomes apparent in puberty when secondary sexual characteristics fail to develop, and testicular changes occur that eventually result in infertility in the majority of those affected. Some mild cases may go undetected with no abnormalities present except infertility. Increased maternal age may be a risk factor.
Symptoms
small penis
small firm testicles
diminished pubic, axillary, and facial hair
sexual dysfunction
enlarged breast tissue (called gynecomastia)
tall stature
abnormal body proportions (long legs, short trunk)
learning disabilities
personality impairment
simian crease (a single crease in the palm)
Note: the severity of symptoms may vary
Signs And Tests
Physical examination (rectal exam) may show an enlarged prostate.
Tests may include:
karyotyping showing 47XXY
semen exam showing low sperm count
decreased serum testosterone level
increased serum luteinizing hormone
increased serum follicle stimulating hormone
Treatment
There is no treatment for the infertility associated with this syndrome. Testosterone therapy will improve the development of secondary sexual characteristics. The testicular changes that lead to infertility are not preventable.
Gynecomastia (enlarged breast tissue) can be treated with plastic surgery if it is disfiguring.
Counseling may be of benefit to people with emotional maladjustment due to sexual dysfunction and to reinforce male identity.
Expectations (Prognosis)
Infertility cannot be treated. With testosterone therapy, a more normal appearance is the general rule.
Complications
The syndrome is associated with an increased risk of breast cancer, pulmonary disease, varicose veins, and osteoporosis