QuestionSBA
QuestionChoice
This patient with 47 XXY karyotype has Klinefelter syndrome. Although prolactin has a role in breast development, elevated prolactin is not typically associated with Klinefelter syndrome. Elevated prolactin levels are more commonly associated with other medical conditions, such as prolactinomas, certain medications and stress.
10025443
d
Elevated prolactin levels
QuestionChoice
This patient with 47 XXY karyotype has Klinefelter syndrome. Elevated LH levels are indeed a common feature of Klinefelter syndrome. In response to testicular dysfunction and decreased testosterone production, the pituitary gland releases higher levels of FSH and LH in an attempt to stimulate the testes. However, LH is not the primary hormone causing gynaecomastia; oestrogen is.
10025442
c
Elevated LH levels
QuestionChoice
This patient with 47 XXY karyotype has Klinefelter syndrome. Elevated FSH levels are indeed a common feature of Klinefelter syndrome. In response to testicular dysfunction and decreased testosterone production, the pituitary gland releases higher levels of FSH and LH in an attempt to stimulate the testes. However, FSH is not the primary hormone causing gynaecomastia; oestrogen is.
10025441
b
Elevated FSH levels
QuestionChoice
This patient with 47 XXY karyotype has Klinefelter syndrome. It is characterised by reduced testosterone levels due to testicular dysfunction and impaired testosterone production. Furthermore, if testosterone levels were to be elevated, it would not cause gynaecomastia. Instead, it would cause hyperandrogenic features such as hirsutism and acne.
10025444
e
Elevated testosterone levels
QuestionChoice
This is the correct answer. This patient with 47 XXY karyotype has Klinefelter syndrome. The additional X chromosome leads to testicular dysfunction, leading to reduced testosterone production. With lower testosterone levels and an inadequate testosterone-to-oestrogen ratio, there is a relative excess of oestrogen in the body. This hormonal imbalance can result in the development of secondary sexual characteristics that are more characteristic of females, such as gynaecomastia and less body and facial hair.
10025440
a
Elevated oestrogen levels
Concept
Chapter
2693
5842
Klinefelter syndrome
Topic
156
Medical Genetics
17486
A 24 year old male attends his GP surgery with difficulty conceiving. He and his partner have been trying to conceive through regular sexual intercourse for around 18 months.

On examination, a tall stature, long limbs, and small testes are noted. There is also evidence of gynaecomastia. A karyotype analysis reveals a 47, XXY chromosomal pattern.

Which of the following hormones is primarily responsible for the development of gynecomastia in this case?
a