Ce diaporama a bien été signalé.
Nous utilisons votre profil LinkedIn et vos données d’activité pour vous proposer des publicités personnalisées et pertinentes. Vous pouvez changer vos préférences de publicités à tout moment.

Klinfelter syndrome

141 vues

Publié le


Publié dans : Santé & Médecine
  • Soyez le premier à commenter

Klinfelter syndrome

  1. 1. Klinefelter INTRODUCTION Klinefelter syndrome is a genetic condition in which a boy is born with an extra X chromosome. Instead of the typical XY chromosomes in men, they have XXY, so this condition is sometimes called XXY syndrome. Men with Klinefelter usually don’t know they have it until they run into problems trying to have a child. There’s no cure, but it can be treated. HISTORY The syndrome was named after American endocrinologist Harry Klinefelter, who in 1942 worked with Fuller Albright and E. C. Reifenstein at Massachusetts General Hospital in Boston, Massachusetts, and first described it in the same year. The account given by Klinefelter came to be known as Klinefelter syndrome as his name appeared first on the published paper, and seminiferous tubule dysgenesis was no longer used. Considering the names of all three researchers, it is sometimes also called Klinefelter–Reifenstein–Albright syndrome In 1956 it was discovered that Klinefelter syndrome resulted from an extra chromosome. Plunkett and Barr found the sex chromatin body in cell nuclei of the body. This was further clarified as XXY in 1959 by Patricia Jacobs and John Anderson Strong. The first published report of a man with a 47,XXY karyotype was by Patricia Jacobs and John Strong at Western General Hospital in Edinburgh, Scotland, in 1959. This karyotype was found in a 24-year-old man who had signs of KS. Jacobs described her discovery of this first reported human or mammalian chromosome aneuploidy in her 1981 William Allan Memorial Award address. EPIDEMIOLOGY This syndrome, evenly distributed in all ethnic groups, has a prevalence of one to two per every 1000 males in the general population it is estimated that only 25% of the individuals with Klinefelter syndrome are diagnosed throughout their lives. 3.1% of infertile males have Klinefelter syndrome. The syndrome is also the main cause of male hypogonadism. CAUSES In this condition get the extra X chromosome by chance. Either the egg or the sperm that came together to create an extra X chromosome. Older women have a slightly higher chance of having a boy with XXY syndrome, but the chance is small. Men with Klinefelter may have:  An extra X chromosome in every cell, which is the most common  An extra X chromosome in only some cells, called mosaic Klinefelter, in which you don’t have as many symptoms  More than one extra X chromosome, which is very rare and more severe
  2. 2. CLINICAL FEATURES Babies:  Hernia  More quiet than usual  Slower to learn to sit up, crawl, and talk  Testicles that haven’t dropped into the scrotum  Weaker muscles Children:  A hard time making friends and talking about feelings  Low energy levels  Problems learning to read, write, and do math  Shyness and low confidence Teenagers:  Larger breasts than normal  Less facial and body hair, and it comes in later  Less muscle tone, and muscles grow slower than usual  Longer arms and legs, wider hips, and a shorter torso than other boys their age  Puberty never comes, comes later, or doesn’t quite finish  Small penis and small, firm testicles  Taller than usual for the family Adults:  Infertility (can’t have children because they can’t make enough sperm)  Low sex drive  Low testosterone levels  Problems getting or keeping an erection
  3. 3. DIAGNOSIS 1- History Collection 2- Physical Examination 3- Hormone testing. Blood or urine samples can reveal abnormal hormone levels that are a sign of Klinefelter syndrome. 4- Chromosome analysis. Also called karyotype analysis, this test is used to confirm a diagnosis of Klinefelter syndrome. A blood sample is sent to the lab to check the shape and number of chromosomes. TREATMENTS There's no cure for Klinefelter syndrome, but some of the problems associated with the condition can be treated if necessary.Possible treatments include:  Testosterone replacement therapy -worksbyincreasingaboy's testosteronelevelsintothe normal range.Additional testosterone canhelpaboywithklinefeltersyndrome developbigger musclesanda deepervoice,aswell aspromote growthof the penisandfacial andbodyhair. It can alsohelpimprove bone densityandreduce the growthof a boy'sbreasts. Testosterone therapycannotincrease the size of a boy'stesticlesorpreventorreverse infertility.  Speech and language therapy during childhood to help with speech development  Educational and behavioural support at school to help with any learning difficulties or behaviour problems  occupational therapy to help with any co-ordination problems associated with dyspraxia  physiotherapy to help build muscle and increase strength  Psychological support for any mental health issues  fertility treatment – options include artificial insemination using donor sperm or possibly intracytoplasmic sperm injection (icsi), where sperm removed during a small operation are used to fertilise an egg in a laboratory  breast reduction surgery to remove excess breast tissue