Klinefelter Syndrome Essay, Research Paper
9 men with enlarged breasts, scanty facial/body hair, small testes, and infertilityKlinefelter Syndrome
I. History
A. 1942, report published Klinefelter et al
9 men with enlarged breasts, scanty facial/body hair, small testes, and infertility
B. 1959, condition named Klinefelter syndrome
Men had extra sex chromosome (XXY), instead of XY
C. Klinefelter is most common male chromosomal disorder linked to infertility and hypogonadism (small testes)
II. Genetic information
A. Typical karyotype: 47, XXY (80-90% patients)
B. Variants to karyotype
Mosaics (10%): 46,XY/47,XXY (fertility possible); 46,XY/48,XXXY; and 47,XXY/48,XXXY
Remaining cases: 48,XXXY; 48XXYY; 49,XXXYY; 49,XXXXY
1%: structurally abnormal X addition to a normal XY
C. Trait received by autosomal recessive inheritance
D. Reciprocal X-Y interchange at paternal meiosis
E. Onset: child born with condition, diagnosis occurs in adulthood
III. Characteristics
A. Severity of symptoms is related to number of extra X chromosomes
B. Physical
Enlarged breasts, gynecomastia
Fatigue, weakness
Erectile dysfunction
Osteoporosis
Subnormal libido
Taller than average male, long thin arms and legs
Taurodontism (enlarged molar teeth)
Sparse facial/body hair
High-pitched voice
Female-type fat distribution
Small testes
C. Cognitive
Mental retardation
Developmental and learning disabilities (academic problems, delayed speech, diminished short-term memory, attention deficit disorder, decreased data-retrieval skills, dyslexia)
Behavioral problems and psychological distress due to poor self-esteem, poor psychosocial development, and decreased ability to deal with stress
Psychiatric disorders: anxiety, depression, neurosis, psychosis
D. Potential consequences
Infertility
Risk of breast cancer is 20X greater than normal male
Cardiac/circulatory problems (mitral valve prolapse, varicose veins, venous ulcers, deep vein thrombosis, pulmonary embolism)
Increased frequency of extragonadal germ cell tumors
IV. Treatment: 3 areas
A. Hypogonadism and Gynecomastia
Androgen therapy: testosterone replacement at puberty to correct androgen deficiency, provide virilization, and improve psychosocial status
Regular testosterone injections to promote strength and hair growth, build muscle, increase libido, enlarge size of testes, improve overall mood and self-image, prevent osteoporosis
Mastectomy to correct gynecomastia, reduce risk of breast cancer, and improve self-image
B. Psychosocial problems
Multidisciplinary team approach to work on speech impairments, academic difficulties, and other behavioral/psychosocial problems
V. Miscellaneous
A. Frequency: 1/500-1000 males
B. Mortality: 40% males survive fetal period, normal life expectancy
No racial predilection exists9 men with enlarged breasts, scanty facial/body hair, small testes, and infertility