This condition was first identified by Dr. Harry Klinefelter at the Massachusetts General Hospital in Boston. A report published he and his coworkers reported case studies on nine men who had enlarged breasts, sparse facial and body hair and an inability to produce sperm.
Now more appropriately referred to as XXY Male of XXY Male Syndrome, males born with this condition have an extra sex chromosome XXY instead of the usual genotype XY. It is associated with a 47XXY karyotype and statistically occurs in 1/500 newborns.
Klinefelter is occasionally associated with lymphatic blockage or fetal hydrops and thus is included in a discussion of developmental disorders of the lymphatics.
Original symptoms included tall stature, long upper extremities, poor pubertal development, microorchidism, enlarged breasts, sparce facial and body hair, small testes and subsequent sterility.
Recent studies have expanded the original symptoms to include infertility, incomplete masculinization; feminine, or pear shaped, body and body hair distribution, decreased libido, osteoporosis, taurodontism, venous disease (which may include mitral valve prolapse, varicose veins and venous ulcers), learning and emotional disorders, autoimmune disorders, low energy and self esteem, communication difficulties, especially with expressive language, frustration-based outbursts, motor skills issue and developmental delays. Also, there is a 20 times increased risk for XXY males to develop breast cancer than non XXY males.
For proper care and treatment early diagnosis is important. The treatment includes hormone therapy such as testosterone replacement. Other treatment aspects should include the psychosocial and emotional problems, needed treatment for physiological side affects and later on even genetic counseling.
FOR FURTHER INFORMATION AND RESOURCES:
- Introductory video about XXY, by mother whose son has Klinefelter Syndrome
- The Even Exchange, Newsletter
Klinefelter Syndrome Support Group Home Page, numerous links to other organizations and resources, created by an adult with Klinefelter Syndrome, regional groups, varients, international groups
Australian Klinefelter Support Group
4 Victoria Rd
Acquire Fields NEW 02564 AUSTRALIA
Victoria Support Group
41 Jesmond RdCordon, Victoria 03136 AUSTRALIA03-9723-6148
Klinefelter Syndrome Support Group
P.O.Box 3Glendenning Mail Center NEW 2761 AUSTRALIA02-9628-4142
Canada Klinefelter Support Group
Apt. 3, 2867 Young St.Toronto, ON. Canada M4N 2J5416. 481.3171
England (United Kingdom)
Sweden and Denmark
Diagnosis and Treatment of Klinefelter Syndrome, CM SMYTH, University of Washington, Hospital Practice, 1999
Guide for XXY Males and Their Families, R Bock, National Institute of Child Health & Human Development (NICHD), National Institutes of Health (NIH)
Klinefelter Syndrome (47,XXY), English & Spanish (.pdf files), Pacific Northwest Regional
Genetics Group (PacNoRGG)
Klinefelter Syndrome (XXY): A Parent's View
Klinefelter Syndrome, eMedicine
Klinefelter Syndrome, Ohio Support Network
Understanding Klinefelter Syndrome: A Guide for XXY Males and their Families, R Boca, INCHED, NIHAU Pub. No. 93-3202, August 1993
Klinefelter’s Syndrome pamphlet and The X-tra Special Boy and For Boys Only, A Supplement pamphlets, by D Plumridge,C Brackets, and S LaFranchi, $3.50 for the main pamphlet and $1.25 for the supplement. Attn: CDRC Publications, Oregon Health Sciences University, CDRC, P.O. Box 574, Portland, Oregon 97207, Phone: (503) 279-8342 - checks to: Child Development & Rehabilitation Center...........