Klinefelter's Syndrome Association UK

Klinefelter's Syndrome is a congenital condition (i.e. something a male is born with and present from the moment of conception) caused by the presence of one or more extra X sex chromosomes.

Studies have shown that the extra X sex chromosome may occur in as often as 1 in 650 live male births and is probably the most common single chromosome variation in the general male population.

KS is usually diagnosed by taking a blood sample which is analysed to reveal that the chromosome pattern is 47XXY or a variant. Other blood tests will look at the level of Testosterone, Sex Hormone Binding Globulin (SHBG), Follicle Stimulating Hormone (FSH) & Lutenising Hormone (LH).

No, KS is a lifelong condition but it can be treated with Testosterone Replacement Therapy so that the individual can live a near normal life.

Testosterone is a controlled drug and is only available on prescription from a doctor. Methods for delivery include: Injections, Gel, Implants, Tablets, Patches, and Slow Release Tablets that are placed in the mouth. Individual choice, as well as, effectiveness, age and ease of use will also influence which method is most suitable.

Testosterone has a variety of effects on behaviour, including increased assertiveness, and in some situations, rather more aggression than usual. But as long as the levels are kept within the standard range, this is entirely normal. It is always sensible to start with small doses and build up the dose gradually to help acclimatise patients and or their relatives to an increase in independence and assertiveness.

The teenage years can be difficult for any boy, but can be particularly stressful for those with KS who have to come to terms with hormone treatment, possible breast development and infertility. Boys will need the support and understanding of their families (counselling may be required). At this time of their life some young men may want to talk to others with KS. The Klinefelter's Syndrome Association holds Local Male Meetings, Activity Weekends and an Annual conference where those with KS can meet.

Some boys with KS appear to have few or no problems at school and have gone on to university, gaining degrees. Given appropriate intervention boys with learning difficulties in early childhood may have overcome their problems by adolescence. Others make progress but continue to have learning difficulties into adulthood.

In terms of the hormone treatment, there is continuing improvement in the methods of delivery of testosterone, and other than the infertility the male with KS should be assured that he should be rendered entirely normal by means of his testosterone replacement treatment in terms of his bone, muscle, hair growth and behaviour.

Note:

The information contained in these Frequently Asked Questions (FAQs) has been approved by our Medical Advisers but should not be treated as specific advice to individuals. All such information should be checked with your Health Provider. Drug usage in particular is a matter for your Medical Practitioner.