Dysfunction of the Male System

Question 1

Identify the main stages of pubertal maturation of male genitalia.

Answer 1

Stage 1: No pubic hair, no enlargement of penis or testes
Stage 2: Testicular enlargement to >2.5 cm, start of pubic hair
Stage 3: Penal enlargement, enlarging testicles, more pubic hair
Stage 4: Further enlargement of scrotum, and testes, darkening of pubic hair
Stage 5: Adult genital appearance

Question 2

What is the average age of males in puberty ? of females ? What are the main events of this in males ?

Answer 2

Boys- 14 years
Girls- 13 years

Height spurt, penis and testes increase in size, pubic hair appears.

Question 3

Distinguish between fast and slow matureres. Does this impact final height ?

Answer 3

Fast maturers begin their growth spurt earlier, but generally all reach around the same size.

Question 4

At what age without puberty do we begin to worry ?

Answer 4

15, certainly 16

Question 5

Identify the main endocrine changes of puberty.

Answer 5

1) Pre-pubertal stage
- low testosterone
- low gonadal steroids
- Hypothalamus is extremely sensitive to that low testosterone production so still switches off LH and FSH
- If at this stage around 14, delayed puberty

2) Initiation of puberty
- At start, still low testosterone
- Higher centers has decreasing sensitivity to testosterone, so FSH and LH (simulates testosterone formation) rise

3) Adult
- Adult levels of testosterone
- Feedback has decreased to adult level
- FSH and LH higher than pre pubertal stage (at adult level) (but respond to this through feedback mechanism)

Question 6

Define hypogonadism, and state its main types.

Answer 6

Circulating testosterone is low, or undetectable (not enough testosterone to give secondary male characteristics and to see over genital maturation).

1) Primary gonadal failure: If abnormality is in the testes then feedback system so anterior pituitary and hypothalamus (with GnRH) sense lack of testosterone, so start producing LH. Soon, seminiferous tubules are not developing, so pours out FSH as well.
2) Secondary gonadal failure: (abnormality in hypothalamus or pituitary) still low testosterone, but also low or no FSH and LH.

Question 7

Identify the main causes of hypogonadism in the phenotypic male.

Answer 7

1) Temporary Delay of Puberty
2) Hypogonadotrophic Hypogonadism (secondary hypogonadism)
3) Hypergonadotrophic Hypogonadism (primary hypogonadism)

Question 8

Identify the main causes of temporary delay of puberty.

Answer 8

• Constitutional delay of puberty (familial, sporadic)
• Chronic illness (e.g. malabsorption (e.g. due to esophagus achalasia, due to anorexia nervosa), malignancy (If pituitary tumor is pressing on cells making GnRH, then do not have enough to stimulate LH and FSH OR the tumor is in hypothalamus/pituitary area itself then get low testosterone with high FSH and LH), malnutrition)
• Hormonal disturbance (e.g. GH deficiency, hypothyroidism (may decrease efficacy of FSH and LH))

Question 9

Identify the main causes of Hypogonadotrophic Hypogonadism.

Answer 9

i.e. stimulation from LH/FSH is lacking

• Kallman’s syndrome (one of its distinctive characteristics is anosmia, lack of functioning olfaction) (cause of failure of development of GnRH cells in hypothalamus, which control release of FSH and LH)
• Hypopituitarism (e.g. trauma, tumor (e.g. pituitary tumor pressing on FSH and LH producing cells such as craniopharynioma))

Question 10

Identify the main causes of Hypergonadotrophic Hypogonadism.

Answer 10

• Klinefelter’s Syndrome (XXY) (e.g. shown by osteoporosis)
• Anorchia
• Orchitis (i.e. inflammation of testes) (e.g. due to mumps)
• Radiation treatment and/or cytotoxic chemotherapy (e.g. in leukemia)
• Surgical or traumatic castration

Question 11

Describe treatment for delayed puberty. Does delayed puberty affect future fertility ?

Answer 11

Short term low dose monthly testosterone (but puberty will likely be reached at some point without the testosterone)
No, as long as he reaches puberty, able to become a father

Question 12

What are the levels of the main hormones in delayed puberty ? Describe any other features of delayed puberty.

Answer 12

• Low LH, FSH, testosterone (basically pre-pubert endocrine stage)
• No testicular development

Question 13

What are the risks of giving high dose testosterone for hypogonadism ? Are there any dangers to testosterone other than this ?

Answer 13

Causes fusion of epiphysis, so halts growth.

No

Question 14

Under which BMI does a delay in puberty occur ?

Answer 14

Under 16-17, gonadotrophins fall so no stimulation to ovaries from FSH

Question 15

State the procedure performed for oesophagus achalasia.

Answer 15

Oesophagomyotomy (Heller’s procedure)

Question 16

What does the presence of absence of pubic hair, size of penis and testes signifiy with respect to hormones ?

Answer 16

Presence of pubic hair, larger penis size means testosterone presence
Absence of those means testosterone absent

Growth of testicles means FSH present, otherwise FSH absent.

Question 17

Identify the main tests performed to investigate hypogonadism.

Answer 17

1) FSH, LH, testosterone

2) Chromosome analysis

Question 18

Describe treatment for hypogonadotrophic hypogonadism. How does hypogonadotrophic hypogonadism affect future fertility ?

Answer 18

Monthly testosterone injections (higher than for delayed puberty)

Patients cannot produce FSH or LH, so no way we can return fertility to them unless we can give them FSH. Following this treatment, patient will recover normal penile size and pubic hair, but testicles will still be small, as there is no FSH to drive testicular growth.

Exogenous GnRH may then be administered to stimulate production of FSH (and LH), allowing for testicular growth and spermatogenesis.
HOWEVER, GnRH is not needed for normal sexual relations so only given when attempting to get pregnant.

Question 19

Craniopharyngioma is a cause of hypogonadotrophic hypogonadism. Identify possible signs and symptoms of it.

Answer 19

Headache
Visual disturbance
Short Stature
Diabetes Insipidus
Arrested growth/sexual development

Question 20

Explain how Klinefelter’s Syndrome can lead to hypergonadotrophic hypogonadism.

Answer 20

Failure of development of seminiferous tubules so feedback mechanism so hypothalamus and pituitary keeps sending more LH and FSH so high FSH and LH. There is some Leydig cell activity but not full, so scanty pubic hair may be present, some puberty there

Question 21

Describe treatment for hypergonadotrophic hypogonadism. How does hypergonadotrophic hypogonadism affect future fertility ?

Answer 21

-Testosterone injections

Question 22

Identify some of the main signs and symptoms of Klinefelter’s.

Answer 22

Gynecomastia
Poor sexual development with hypogonadism
Small penis
Scanty pubic hair
Osteoporosis with collapse vertebrae (due to testosterone deficiency)

Question 23

Describe treatment for hypergonadotrophic hypogonadism due to Klinefelter’s.

Answer 23

-Testosterone replacement

• Biphosphonates and Calcium supplements (for osteoporosis)
• Reduction mammoplasty (for gynecomastia)

Question 24

Identify the main symptoms of male hypogonadism.

Answer 24

• Sexual dysfunction
• Fatigue
• Depressed mood
• Osteoporosis
• Decreased in muscle mass and strength
• Loss of facial and body hair

Question 25

How is testosterone replacement administered ?

Answer 25

-IM injections (every 2-3 weeks)
OR
-Oral (3-4 times daily)
OR 
-SC pellets (every 4-6 months)
BUT ALSO 
-Transdermal
-Buccal