Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

10 Cards in this Set

  • Front
  • Back
The History of Klinefelters
-Klinefelteret al. (1942) reported on 9 men with enlarged breasts, sparse facial and body hair, small testes, and inability to produce sperm

-In 1959, it was discovered that these men had an extra sex chromosome (XXY)
Klinefeltersyndrome AKA testicular dysgenesis

-Most common chromosomal disorder associated with male hypogonadismand infertility

-Most males go through life without being diagnosed
-Diagnosis, when made, usually occurs in adulthood due to hypogonadismand infertility
Is it inherited?
This condition is not inherited, but usually occurs as a random event during the formation of reproductive cells (eggs and sperm). An error in cell division called nondisjunctioncan result in reproductive cells with an abnormal number of chromosomes.
What is the pathophysiology
-Phenotypic abnormalities, including mental retardation, directly related to number of extra X chromosomes

-Intelligence quotient (IQ) reduced by ~ 15 points for each extra X chromosome

-49, XXXXY more severe than 48, XXXY

-No racial predilection exists

-Seen in males only
Major consequences of extra “X”
-Small, firm testicles
-Small penis
-Sparse pubic, axillae, and facial hair
-Sexual problems
-Tall stature
-Abnormal body proportions
-Long legs, short trunk
-Approximately 1 in 500 to 1,000 males born with extra sex chromosome in U.S.

-Over 3,000 affected males born yearly

-Prevalence is 5 to 20 times higher in the mentally retarded than in general newborn population

-About 40% of conceptiwith KF survive the fetal period
Fun Facts
Most 47, XXY have normal intelligence

-Some may have behavioral and/or psychological problems

–may be due to poor self-esteem

-Mitralvalve prolapsein 55% of patients

-Varicose veins occur in 20 to 40% of pts
What are the lab studies?
-Hormone profile
-High plasma FSH, LH, and estradiollevels
-Low plasma testosterone levels
-Low semen count
-Echocardiography to detect mitralvalve prolapse
Should address three major facets of the disease

1. Hypogonadism, gynecomastia, and psychosocial problems

2. Testosterone replacement should begin at puberty

3. Plastic surgery for gynecomastia
-Risk of breast carcinoma as high as 20 times that of healthy men

-Slight increase in acute leukemia, Hodgkin and non-Hodgkin lymphomas, CML, and gonadaltumors